![zhangyi (F)](/assets/img/avatar_default.png)
In the ext4 filesystem with errors=panic, if one process is recording
errno in the superblock when invoking jbd2_journal_abort() due to some
error cases, it could be raced by another __ext4_abort() which is
setting the SB_RDONLY flag but missing panic because errno has not been
recorded.
jbd2_journal_commit_transaction()
jbd2_journal_abort()
journal->j_flags |= JBD2_ABORT;
jbd2_journal_update_sb_errno()
| ext4_journal_check_start()
| __ext4_abort()
| sb->s_flags |= SB_RDONLY;
| if (!JBD2_REC_ERR)
| return;
journal->j_flags |= JBD2_REC_ERR;
Finally, it will no longer trigger panic because the filesystem has
already been set read-only. Fix this by introduce j_abort_mutex to make
sure journal abort is completed before panic, and remove JBD2_REC_ERR
flag.
Fixes: 4327ba52af
("ext4, jbd2: ensure entering into panic after recording an error in superblock")
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200609073540.3810702-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2765 lines
77 KiB
C
2765 lines
77 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* linux/fs/jbd2/journal.c
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*
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* Written by Stephen C. Tweedie <sct@redhat.com>, 1998
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*
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* Copyright 1998 Red Hat corp --- All Rights Reserved
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*
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* Generic filesystem journal-writing code; part of the ext2fs
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* journaling system.
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*
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* This file manages journals: areas of disk reserved for logging
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* transactional updates. This includes the kernel journaling thread
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* which is responsible for scheduling updates to the log.
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*
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* We do not actually manage the physical storage of the journal in this
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* file: that is left to a per-journal policy function, which allows us
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* to store the journal within a filesystem-specified area for ext2
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* journaling (ext2 can use a reserved inode for storing the log).
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*/
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#include <linux/module.h>
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#include <linux/time.h>
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#include <linux/fs.h>
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#include <linux/jbd2.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/freezer.h>
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#include <linux/pagemap.h>
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#include <linux/kthread.h>
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#include <linux/poison.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/math64.h>
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#include <linux/hash.h>
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#include <linux/log2.h>
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#include <linux/vmalloc.h>
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#include <linux/backing-dev.h>
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#include <linux/bitops.h>
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#include <linux/ratelimit.h>
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#include <linux/sched/mm.h>
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#define CREATE_TRACE_POINTS
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#include <trace/events/jbd2.h>
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#include <linux/uaccess.h>
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#include <asm/page.h>
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#ifdef CONFIG_JBD2_DEBUG
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ushort jbd2_journal_enable_debug __read_mostly;
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EXPORT_SYMBOL(jbd2_journal_enable_debug);
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module_param_named(jbd2_debug, jbd2_journal_enable_debug, ushort, 0644);
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MODULE_PARM_DESC(jbd2_debug, "Debugging level for jbd2");
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#endif
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EXPORT_SYMBOL(jbd2_journal_extend);
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EXPORT_SYMBOL(jbd2_journal_stop);
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EXPORT_SYMBOL(jbd2_journal_lock_updates);
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EXPORT_SYMBOL(jbd2_journal_unlock_updates);
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EXPORT_SYMBOL(jbd2_journal_get_write_access);
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EXPORT_SYMBOL(jbd2_journal_get_create_access);
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EXPORT_SYMBOL(jbd2_journal_get_undo_access);
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EXPORT_SYMBOL(jbd2_journal_set_triggers);
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EXPORT_SYMBOL(jbd2_journal_dirty_metadata);
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EXPORT_SYMBOL(jbd2_journal_forget);
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EXPORT_SYMBOL(jbd2_journal_flush);
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EXPORT_SYMBOL(jbd2_journal_revoke);
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EXPORT_SYMBOL(jbd2_journal_init_dev);
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EXPORT_SYMBOL(jbd2_journal_init_inode);
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EXPORT_SYMBOL(jbd2_journal_check_used_features);
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EXPORT_SYMBOL(jbd2_journal_check_available_features);
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EXPORT_SYMBOL(jbd2_journal_set_features);
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EXPORT_SYMBOL(jbd2_journal_load);
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EXPORT_SYMBOL(jbd2_journal_destroy);
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EXPORT_SYMBOL(jbd2_journal_abort);
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EXPORT_SYMBOL(jbd2_journal_errno);
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EXPORT_SYMBOL(jbd2_journal_ack_err);
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EXPORT_SYMBOL(jbd2_journal_clear_err);
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EXPORT_SYMBOL(jbd2_log_wait_commit);
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EXPORT_SYMBOL(jbd2_log_start_commit);
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EXPORT_SYMBOL(jbd2_journal_start_commit);
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EXPORT_SYMBOL(jbd2_journal_force_commit_nested);
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EXPORT_SYMBOL(jbd2_journal_wipe);
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EXPORT_SYMBOL(jbd2_journal_blocks_per_page);
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EXPORT_SYMBOL(jbd2_journal_invalidatepage);
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EXPORT_SYMBOL(jbd2_journal_try_to_free_buffers);
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EXPORT_SYMBOL(jbd2_journal_force_commit);
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EXPORT_SYMBOL(jbd2_journal_inode_ranged_write);
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EXPORT_SYMBOL(jbd2_journal_inode_ranged_wait);
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EXPORT_SYMBOL(jbd2_journal_init_jbd_inode);
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EXPORT_SYMBOL(jbd2_journal_release_jbd_inode);
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EXPORT_SYMBOL(jbd2_journal_begin_ordered_truncate);
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EXPORT_SYMBOL(jbd2_inode_cache);
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static int jbd2_journal_create_slab(size_t slab_size);
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#ifdef CONFIG_JBD2_DEBUG
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void __jbd2_debug(int level, const char *file, const char *func,
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unsigned int line, const char *fmt, ...)
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{
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struct va_format vaf;
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va_list args;
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if (level > jbd2_journal_enable_debug)
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return;
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va_start(args, fmt);
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vaf.fmt = fmt;
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vaf.va = &args;
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printk(KERN_DEBUG "%s: (%s, %u): %pV", file, func, line, &vaf);
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va_end(args);
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}
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EXPORT_SYMBOL(__jbd2_debug);
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#endif
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/* Checksumming functions */
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static int jbd2_verify_csum_type(journal_t *j, journal_superblock_t *sb)
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{
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if (!jbd2_journal_has_csum_v2or3_feature(j))
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return 1;
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return sb->s_checksum_type == JBD2_CRC32C_CHKSUM;
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}
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static __be32 jbd2_superblock_csum(journal_t *j, journal_superblock_t *sb)
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{
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__u32 csum;
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__be32 old_csum;
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old_csum = sb->s_checksum;
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sb->s_checksum = 0;
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csum = jbd2_chksum(j, ~0, (char *)sb, sizeof(journal_superblock_t));
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sb->s_checksum = old_csum;
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return cpu_to_be32(csum);
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}
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/*
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* Helper function used to manage commit timeouts
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*/
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static void commit_timeout(struct timer_list *t)
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{
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journal_t *journal = from_timer(journal, t, j_commit_timer);
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wake_up_process(journal->j_task);
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}
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/*
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* kjournald2: The main thread function used to manage a logging device
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* journal.
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*
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* This kernel thread is responsible for two things:
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*
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* 1) COMMIT: Every so often we need to commit the current state of the
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* filesystem to disk. The journal thread is responsible for writing
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* all of the metadata buffers to disk.
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*
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* 2) CHECKPOINT: We cannot reuse a used section of the log file until all
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* of the data in that part of the log has been rewritten elsewhere on
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* the disk. Flushing these old buffers to reclaim space in the log is
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* known as checkpointing, and this thread is responsible for that job.
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*/
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static int kjournald2(void *arg)
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{
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journal_t *journal = arg;
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transaction_t *transaction;
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/*
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* Set up an interval timer which can be used to trigger a commit wakeup
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* after the commit interval expires
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*/
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timer_setup(&journal->j_commit_timer, commit_timeout, 0);
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set_freezable();
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/* Record that the journal thread is running */
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journal->j_task = current;
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wake_up(&journal->j_wait_done_commit);
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/*
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* Make sure that no allocations from this kernel thread will ever
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* recurse to the fs layer because we are responsible for the
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* transaction commit and any fs involvement might get stuck waiting for
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* the trasn. commit.
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*/
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memalloc_nofs_save();
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/*
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* And now, wait forever for commit wakeup events.
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*/
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write_lock(&journal->j_state_lock);
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loop:
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if (journal->j_flags & JBD2_UNMOUNT)
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goto end_loop;
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jbd_debug(1, "commit_sequence=%u, commit_request=%u\n",
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journal->j_commit_sequence, journal->j_commit_request);
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if (journal->j_commit_sequence != journal->j_commit_request) {
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jbd_debug(1, "OK, requests differ\n");
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write_unlock(&journal->j_state_lock);
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del_timer_sync(&journal->j_commit_timer);
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jbd2_journal_commit_transaction(journal);
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write_lock(&journal->j_state_lock);
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goto loop;
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}
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wake_up(&journal->j_wait_done_commit);
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if (freezing(current)) {
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/*
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* The simpler the better. Flushing journal isn't a
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* good idea, because that depends on threads that may
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* be already stopped.
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*/
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jbd_debug(1, "Now suspending kjournald2\n");
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write_unlock(&journal->j_state_lock);
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try_to_freeze();
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write_lock(&journal->j_state_lock);
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} else {
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/*
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* We assume on resume that commits are already there,
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* so we don't sleep
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*/
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DEFINE_WAIT(wait);
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int should_sleep = 1;
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prepare_to_wait(&journal->j_wait_commit, &wait,
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TASK_INTERRUPTIBLE);
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if (journal->j_commit_sequence != journal->j_commit_request)
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should_sleep = 0;
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transaction = journal->j_running_transaction;
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if (transaction && time_after_eq(jiffies,
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transaction->t_expires))
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should_sleep = 0;
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if (journal->j_flags & JBD2_UNMOUNT)
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should_sleep = 0;
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if (should_sleep) {
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write_unlock(&journal->j_state_lock);
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schedule();
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write_lock(&journal->j_state_lock);
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}
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finish_wait(&journal->j_wait_commit, &wait);
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}
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jbd_debug(1, "kjournald2 wakes\n");
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/*
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* Were we woken up by a commit wakeup event?
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*/
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transaction = journal->j_running_transaction;
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if (transaction && time_after_eq(jiffies, transaction->t_expires)) {
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journal->j_commit_request = transaction->t_tid;
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jbd_debug(1, "woke because of timeout\n");
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}
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goto loop;
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end_loop:
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del_timer_sync(&journal->j_commit_timer);
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journal->j_task = NULL;
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wake_up(&journal->j_wait_done_commit);
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jbd_debug(1, "Journal thread exiting.\n");
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write_unlock(&journal->j_state_lock);
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return 0;
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}
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static int jbd2_journal_start_thread(journal_t *journal)
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{
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struct task_struct *t;
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t = kthread_run(kjournald2, journal, "jbd2/%s",
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journal->j_devname);
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if (IS_ERR(t))
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return PTR_ERR(t);
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wait_event(journal->j_wait_done_commit, journal->j_task != NULL);
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return 0;
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}
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static void journal_kill_thread(journal_t *journal)
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{
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write_lock(&journal->j_state_lock);
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journal->j_flags |= JBD2_UNMOUNT;
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while (journal->j_task) {
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write_unlock(&journal->j_state_lock);
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wake_up(&journal->j_wait_commit);
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wait_event(journal->j_wait_done_commit, journal->j_task == NULL);
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write_lock(&journal->j_state_lock);
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}
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write_unlock(&journal->j_state_lock);
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}
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/*
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* jbd2_journal_write_metadata_buffer: write a metadata buffer to the journal.
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*
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* Writes a metadata buffer to a given disk block. The actual IO is not
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* performed but a new buffer_head is constructed which labels the data
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* to be written with the correct destination disk block.
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*
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* Any magic-number escaping which needs to be done will cause a
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* copy-out here. If the buffer happens to start with the
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* JBD2_MAGIC_NUMBER, then we can't write it to the log directly: the
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* magic number is only written to the log for descripter blocks. In
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* this case, we copy the data and replace the first word with 0, and we
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* return a result code which indicates that this buffer needs to be
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* marked as an escaped buffer in the corresponding log descriptor
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* block. The missing word can then be restored when the block is read
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* during recovery.
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*
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* If the source buffer has already been modified by a new transaction
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* since we took the last commit snapshot, we use the frozen copy of
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* that data for IO. If we end up using the existing buffer_head's data
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* for the write, then we have to make sure nobody modifies it while the
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* IO is in progress. do_get_write_access() handles this.
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*
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* The function returns a pointer to the buffer_head to be used for IO.
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*
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*
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* Return value:
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* <0: Error
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* >=0: Finished OK
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*
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* On success:
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* Bit 0 set == escape performed on the data
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* Bit 1 set == buffer copy-out performed (kfree the data after IO)
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*/
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int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
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struct journal_head *jh_in,
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struct buffer_head **bh_out,
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sector_t blocknr)
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{
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int need_copy_out = 0;
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int done_copy_out = 0;
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int do_escape = 0;
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char *mapped_data;
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struct buffer_head *new_bh;
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struct page *new_page;
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unsigned int new_offset;
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struct buffer_head *bh_in = jh2bh(jh_in);
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journal_t *journal = transaction->t_journal;
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/*
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* The buffer really shouldn't be locked: only the current committing
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* transaction is allowed to write it, so nobody else is allowed
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* to do any IO.
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*
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* akpm: except if we're journalling data, and write() output is
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* also part of a shared mapping, and another thread has
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* decided to launch a writepage() against this buffer.
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*/
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J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in));
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new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
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/* keep subsequent assertions sane */
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atomic_set(&new_bh->b_count, 1);
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spin_lock(&jh_in->b_state_lock);
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repeat:
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/*
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* If a new transaction has already done a buffer copy-out, then
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* we use that version of the data for the commit.
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*/
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if (jh_in->b_frozen_data) {
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done_copy_out = 1;
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new_page = virt_to_page(jh_in->b_frozen_data);
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new_offset = offset_in_page(jh_in->b_frozen_data);
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} else {
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new_page = jh2bh(jh_in)->b_page;
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new_offset = offset_in_page(jh2bh(jh_in)->b_data);
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}
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mapped_data = kmap_atomic(new_page);
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/*
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* Fire data frozen trigger if data already wasn't frozen. Do this
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* before checking for escaping, as the trigger may modify the magic
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* offset. If a copy-out happens afterwards, it will have the correct
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* data in the buffer.
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*/
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if (!done_copy_out)
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jbd2_buffer_frozen_trigger(jh_in, mapped_data + new_offset,
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jh_in->b_triggers);
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/*
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* Check for escaping
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*/
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if (*((__be32 *)(mapped_data + new_offset)) ==
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cpu_to_be32(JBD2_MAGIC_NUMBER)) {
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need_copy_out = 1;
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do_escape = 1;
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}
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kunmap_atomic(mapped_data);
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|
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/*
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* Do we need to do a data copy?
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*/
|
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if (need_copy_out && !done_copy_out) {
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char *tmp;
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spin_unlock(&jh_in->b_state_lock);
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tmp = jbd2_alloc(bh_in->b_size, GFP_NOFS);
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if (!tmp) {
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brelse(new_bh);
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return -ENOMEM;
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}
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spin_lock(&jh_in->b_state_lock);
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if (jh_in->b_frozen_data) {
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jbd2_free(tmp, bh_in->b_size);
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goto repeat;
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}
|
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|
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jh_in->b_frozen_data = tmp;
|
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mapped_data = kmap_atomic(new_page);
|
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memcpy(tmp, mapped_data + new_offset, bh_in->b_size);
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kunmap_atomic(mapped_data);
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|
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new_page = virt_to_page(tmp);
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new_offset = offset_in_page(tmp);
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done_copy_out = 1;
|
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|
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/*
|
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* This isn't strictly necessary, as we're using frozen
|
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* data for the escaping, but it keeps consistency with
|
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* b_frozen_data usage.
|
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*/
|
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jh_in->b_frozen_triggers = jh_in->b_triggers;
|
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}
|
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|
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/*
|
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* Did we need to do an escaping? Now we've done all the
|
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* copying, we can finally do so.
|
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*/
|
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if (do_escape) {
|
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mapped_data = kmap_atomic(new_page);
|
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*((unsigned int *)(mapped_data + new_offset)) = 0;
|
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kunmap_atomic(mapped_data);
|
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}
|
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|
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set_bh_page(new_bh, new_page, new_offset);
|
|
new_bh->b_size = bh_in->b_size;
|
|
new_bh->b_bdev = journal->j_dev;
|
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new_bh->b_blocknr = blocknr;
|
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new_bh->b_private = bh_in;
|
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set_buffer_mapped(new_bh);
|
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set_buffer_dirty(new_bh);
|
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|
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*bh_out = new_bh;
|
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|
|
/*
|
|
* The to-be-written buffer needs to get moved to the io queue,
|
|
* and the original buffer whose contents we are shadowing or
|
|
* copying is moved to the transaction's shadow queue.
|
|
*/
|
|
JBUFFER_TRACE(jh_in, "file as BJ_Shadow");
|
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spin_lock(&journal->j_list_lock);
|
|
__jbd2_journal_file_buffer(jh_in, transaction, BJ_Shadow);
|
|
spin_unlock(&journal->j_list_lock);
|
|
set_buffer_shadow(bh_in);
|
|
spin_unlock(&jh_in->b_state_lock);
|
|
|
|
return do_escape | (done_copy_out << 1);
|
|
}
|
|
|
|
/*
|
|
* Allocation code for the journal file. Manage the space left in the
|
|
* journal, so that we can begin checkpointing when appropriate.
|
|
*/
|
|
|
|
/*
|
|
* Called with j_state_lock locked for writing.
|
|
* Returns true if a transaction commit was started.
|
|
*/
|
|
int __jbd2_log_start_commit(journal_t *journal, tid_t target)
|
|
{
|
|
/* Return if the txn has already requested to be committed */
|
|
if (journal->j_commit_request == target)
|
|
return 0;
|
|
|
|
/*
|
|
* The only transaction we can possibly wait upon is the
|
|
* currently running transaction (if it exists). Otherwise,
|
|
* the target tid must be an old one.
|
|
*/
|
|
if (journal->j_running_transaction &&
|
|
journal->j_running_transaction->t_tid == target) {
|
|
/*
|
|
* We want a new commit: OK, mark the request and wakeup the
|
|
* commit thread. We do _not_ do the commit ourselves.
|
|
*/
|
|
|
|
journal->j_commit_request = target;
|
|
jbd_debug(1, "JBD2: requesting commit %u/%u\n",
|
|
journal->j_commit_request,
|
|
journal->j_commit_sequence);
|
|
journal->j_running_transaction->t_requested = jiffies;
|
|
wake_up(&journal->j_wait_commit);
|
|
return 1;
|
|
} else if (!tid_geq(journal->j_commit_request, target))
|
|
/* This should never happen, but if it does, preserve
|
|
the evidence before kjournald goes into a loop and
|
|
increments j_commit_sequence beyond all recognition. */
|
|
WARN_ONCE(1, "JBD2: bad log_start_commit: %u %u %u %u\n",
|
|
journal->j_commit_request,
|
|
journal->j_commit_sequence,
|
|
target, journal->j_running_transaction ?
|
|
journal->j_running_transaction->t_tid : 0);
|
|
return 0;
|
|
}
|
|
|
|
int jbd2_log_start_commit(journal_t *journal, tid_t tid)
|
|
{
|
|
int ret;
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
ret = __jbd2_log_start_commit(journal, tid);
|
|
write_unlock(&journal->j_state_lock);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Force and wait any uncommitted transactions. We can only force the running
|
|
* transaction if we don't have an active handle, otherwise, we will deadlock.
|
|
* Returns: <0 in case of error,
|
|
* 0 if nothing to commit,
|
|
* 1 if transaction was successfully committed.
|
|
*/
|
|
static int __jbd2_journal_force_commit(journal_t *journal)
|
|
{
|
|
transaction_t *transaction = NULL;
|
|
tid_t tid;
|
|
int need_to_start = 0, ret = 0;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_running_transaction && !current->journal_info) {
|
|
transaction = journal->j_running_transaction;
|
|
if (!tid_geq(journal->j_commit_request, transaction->t_tid))
|
|
need_to_start = 1;
|
|
} else if (journal->j_committing_transaction)
|
|
transaction = journal->j_committing_transaction;
|
|
|
|
if (!transaction) {
|
|
/* Nothing to commit */
|
|
read_unlock(&journal->j_state_lock);
|
|
return 0;
|
|
}
|
|
tid = transaction->t_tid;
|
|
read_unlock(&journal->j_state_lock);
|
|
if (need_to_start)
|
|
jbd2_log_start_commit(journal, tid);
|
|
ret = jbd2_log_wait_commit(journal, tid);
|
|
if (!ret)
|
|
ret = 1;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Force and wait upon a commit if the calling process is not within
|
|
* transaction. This is used for forcing out undo-protected data which contains
|
|
* bitmaps, when the fs is running out of space.
|
|
*
|
|
* @journal: journal to force
|
|
* Returns true if progress was made.
|
|
*/
|
|
int jbd2_journal_force_commit_nested(journal_t *journal)
|
|
{
|
|
int ret;
|
|
|
|
ret = __jbd2_journal_force_commit(journal);
|
|
return ret > 0;
|
|
}
|
|
|
|
/**
|
|
* int journal_force_commit() - force any uncommitted transactions
|
|
* @journal: journal to force
|
|
*
|
|
* Caller want unconditional commit. We can only force the running transaction
|
|
* if we don't have an active handle, otherwise, we will deadlock.
|
|
*/
|
|
int jbd2_journal_force_commit(journal_t *journal)
|
|
{
|
|
int ret;
|
|
|
|
J_ASSERT(!current->journal_info);
|
|
ret = __jbd2_journal_force_commit(journal);
|
|
if (ret > 0)
|
|
ret = 0;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Start a commit of the current running transaction (if any). Returns true
|
|
* if a transaction is going to be committed (or is currently already
|
|
* committing), and fills its tid in at *ptid
|
|
*/
|
|
int jbd2_journal_start_commit(journal_t *journal, tid_t *ptid)
|
|
{
|
|
int ret = 0;
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
if (journal->j_running_transaction) {
|
|
tid_t tid = journal->j_running_transaction->t_tid;
|
|
|
|
__jbd2_log_start_commit(journal, tid);
|
|
/* There's a running transaction and we've just made sure
|
|
* it's commit has been scheduled. */
|
|
if (ptid)
|
|
*ptid = tid;
|
|
ret = 1;
|
|
} else if (journal->j_committing_transaction) {
|
|
/*
|
|
* If commit has been started, then we have to wait for
|
|
* completion of that transaction.
|
|
*/
|
|
if (ptid)
|
|
*ptid = journal->j_committing_transaction->t_tid;
|
|
ret = 1;
|
|
}
|
|
write_unlock(&journal->j_state_lock);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Return 1 if a given transaction has not yet sent barrier request
|
|
* connected with a transaction commit. If 0 is returned, transaction
|
|
* may or may not have sent the barrier. Used to avoid sending barrier
|
|
* twice in common cases.
|
|
*/
|
|
int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid)
|
|
{
|
|
int ret = 0;
|
|
transaction_t *commit_trans;
|
|
|
|
if (!(journal->j_flags & JBD2_BARRIER))
|
|
return 0;
|
|
read_lock(&journal->j_state_lock);
|
|
/* Transaction already committed? */
|
|
if (tid_geq(journal->j_commit_sequence, tid))
|
|
goto out;
|
|
commit_trans = journal->j_committing_transaction;
|
|
if (!commit_trans || commit_trans->t_tid != tid) {
|
|
ret = 1;
|
|
goto out;
|
|
}
|
|
/*
|
|
* Transaction is being committed and we already proceeded to
|
|
* submitting a flush to fs partition?
|
|
*/
|
|
if (journal->j_fs_dev != journal->j_dev) {
|
|
if (!commit_trans->t_need_data_flush ||
|
|
commit_trans->t_state >= T_COMMIT_DFLUSH)
|
|
goto out;
|
|
} else {
|
|
if (commit_trans->t_state >= T_COMMIT_JFLUSH)
|
|
goto out;
|
|
}
|
|
ret = 1;
|
|
out:
|
|
read_unlock(&journal->j_state_lock);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(jbd2_trans_will_send_data_barrier);
|
|
|
|
/*
|
|
* Wait for a specified commit to complete.
|
|
* The caller may not hold the journal lock.
|
|
*/
|
|
int jbd2_log_wait_commit(journal_t *journal, tid_t tid)
|
|
{
|
|
int err = 0;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
#ifdef CONFIG_PROVE_LOCKING
|
|
/*
|
|
* Some callers make sure transaction is already committing and in that
|
|
* case we cannot block on open handles anymore. So don't warn in that
|
|
* case.
|
|
*/
|
|
if (tid_gt(tid, journal->j_commit_sequence) &&
|
|
(!journal->j_committing_transaction ||
|
|
journal->j_committing_transaction->t_tid != tid)) {
|
|
read_unlock(&journal->j_state_lock);
|
|
jbd2_might_wait_for_commit(journal);
|
|
read_lock(&journal->j_state_lock);
|
|
}
|
|
#endif
|
|
#ifdef CONFIG_JBD2_DEBUG
|
|
if (!tid_geq(journal->j_commit_request, tid)) {
|
|
printk(KERN_ERR
|
|
"%s: error: j_commit_request=%u, tid=%u\n",
|
|
__func__, journal->j_commit_request, tid);
|
|
}
|
|
#endif
|
|
while (tid_gt(tid, journal->j_commit_sequence)) {
|
|
jbd_debug(1, "JBD2: want %u, j_commit_sequence=%u\n",
|
|
tid, journal->j_commit_sequence);
|
|
read_unlock(&journal->j_state_lock);
|
|
wake_up(&journal->j_wait_commit);
|
|
wait_event(journal->j_wait_done_commit,
|
|
!tid_gt(tid, journal->j_commit_sequence));
|
|
read_lock(&journal->j_state_lock);
|
|
}
|
|
read_unlock(&journal->j_state_lock);
|
|
|
|
if (unlikely(is_journal_aborted(journal)))
|
|
err = -EIO;
|
|
return err;
|
|
}
|
|
|
|
/* Return 1 when transaction with given tid has already committed. */
|
|
int jbd2_transaction_committed(journal_t *journal, tid_t tid)
|
|
{
|
|
int ret = 1;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_running_transaction &&
|
|
journal->j_running_transaction->t_tid == tid)
|
|
ret = 0;
|
|
if (journal->j_committing_transaction &&
|
|
journal->j_committing_transaction->t_tid == tid)
|
|
ret = 0;
|
|
read_unlock(&journal->j_state_lock);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(jbd2_transaction_committed);
|
|
|
|
/*
|
|
* When this function returns the transaction corresponding to tid
|
|
* will be completed. If the transaction has currently running, start
|
|
* committing that transaction before waiting for it to complete. If
|
|
* the transaction id is stale, it is by definition already completed,
|
|
* so just return SUCCESS.
|
|
*/
|
|
int jbd2_complete_transaction(journal_t *journal, tid_t tid)
|
|
{
|
|
int need_to_wait = 1;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_running_transaction &&
|
|
journal->j_running_transaction->t_tid == tid) {
|
|
if (journal->j_commit_request != tid) {
|
|
/* transaction not yet started, so request it */
|
|
read_unlock(&journal->j_state_lock);
|
|
jbd2_log_start_commit(journal, tid);
|
|
goto wait_commit;
|
|
}
|
|
} else if (!(journal->j_committing_transaction &&
|
|
journal->j_committing_transaction->t_tid == tid))
|
|
need_to_wait = 0;
|
|
read_unlock(&journal->j_state_lock);
|
|
if (!need_to_wait)
|
|
return 0;
|
|
wait_commit:
|
|
return jbd2_log_wait_commit(journal, tid);
|
|
}
|
|
EXPORT_SYMBOL(jbd2_complete_transaction);
|
|
|
|
/*
|
|
* Log buffer allocation routines:
|
|
*/
|
|
|
|
int jbd2_journal_next_log_block(journal_t *journal, unsigned long long *retp)
|
|
{
|
|
unsigned long blocknr;
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
J_ASSERT(journal->j_free > 1);
|
|
|
|
blocknr = journal->j_head;
|
|
journal->j_head++;
|
|
journal->j_free--;
|
|
if (journal->j_head == journal->j_last)
|
|
journal->j_head = journal->j_first;
|
|
write_unlock(&journal->j_state_lock);
|
|
return jbd2_journal_bmap(journal, blocknr, retp);
|
|
}
|
|
|
|
/*
|
|
* Conversion of logical to physical block numbers for the journal
|
|
*
|
|
* On external journals the journal blocks are identity-mapped, so
|
|
* this is a no-op. If needed, we can use j_blk_offset - everything is
|
|
* ready.
|
|
*/
|
|
int jbd2_journal_bmap(journal_t *journal, unsigned long blocknr,
|
|
unsigned long long *retp)
|
|
{
|
|
int err = 0;
|
|
unsigned long long ret;
|
|
sector_t block = 0;
|
|
|
|
if (journal->j_inode) {
|
|
block = blocknr;
|
|
ret = bmap(journal->j_inode, &block);
|
|
|
|
if (ret || !block) {
|
|
printk(KERN_ALERT "%s: journal block not found "
|
|
"at offset %lu on %s\n",
|
|
__func__, blocknr, journal->j_devname);
|
|
err = -EIO;
|
|
jbd2_journal_abort(journal, err);
|
|
} else {
|
|
*retp = block;
|
|
}
|
|
|
|
} else {
|
|
*retp = blocknr; /* +journal->j_blk_offset */
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* We play buffer_head aliasing tricks to write data/metadata blocks to
|
|
* the journal without copying their contents, but for journal
|
|
* descriptor blocks we do need to generate bona fide buffers.
|
|
*
|
|
* After the caller of jbd2_journal_get_descriptor_buffer() has finished modifying
|
|
* the buffer's contents they really should run flush_dcache_page(bh->b_page).
|
|
* But we don't bother doing that, so there will be coherency problems with
|
|
* mmaps of blockdevs which hold live JBD-controlled filesystems.
|
|
*/
|
|
struct buffer_head *
|
|
jbd2_journal_get_descriptor_buffer(transaction_t *transaction, int type)
|
|
{
|
|
journal_t *journal = transaction->t_journal;
|
|
struct buffer_head *bh;
|
|
unsigned long long blocknr;
|
|
journal_header_t *header;
|
|
int err;
|
|
|
|
err = jbd2_journal_next_log_block(journal, &blocknr);
|
|
|
|
if (err)
|
|
return NULL;
|
|
|
|
bh = __getblk(journal->j_dev, blocknr, journal->j_blocksize);
|
|
if (!bh)
|
|
return NULL;
|
|
atomic_dec(&transaction->t_outstanding_credits);
|
|
lock_buffer(bh);
|
|
memset(bh->b_data, 0, journal->j_blocksize);
|
|
header = (journal_header_t *)bh->b_data;
|
|
header->h_magic = cpu_to_be32(JBD2_MAGIC_NUMBER);
|
|
header->h_blocktype = cpu_to_be32(type);
|
|
header->h_sequence = cpu_to_be32(transaction->t_tid);
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
BUFFER_TRACE(bh, "return this buffer");
|
|
return bh;
|
|
}
|
|
|
|
void jbd2_descriptor_block_csum_set(journal_t *j, struct buffer_head *bh)
|
|
{
|
|
struct jbd2_journal_block_tail *tail;
|
|
__u32 csum;
|
|
|
|
if (!jbd2_journal_has_csum_v2or3(j))
|
|
return;
|
|
|
|
tail = (struct jbd2_journal_block_tail *)(bh->b_data + j->j_blocksize -
|
|
sizeof(struct jbd2_journal_block_tail));
|
|
tail->t_checksum = 0;
|
|
csum = jbd2_chksum(j, j->j_csum_seed, bh->b_data, j->j_blocksize);
|
|
tail->t_checksum = cpu_to_be32(csum);
|
|
}
|
|
|
|
/*
|
|
* Return tid of the oldest transaction in the journal and block in the journal
|
|
* where the transaction starts.
|
|
*
|
|
* If the journal is now empty, return which will be the next transaction ID
|
|
* we will write and where will that transaction start.
|
|
*
|
|
* The return value is 0 if journal tail cannot be pushed any further, 1 if
|
|
* it can.
|
|
*/
|
|
int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid,
|
|
unsigned long *block)
|
|
{
|
|
transaction_t *transaction;
|
|
int ret;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
spin_lock(&journal->j_list_lock);
|
|
transaction = journal->j_checkpoint_transactions;
|
|
if (transaction) {
|
|
*tid = transaction->t_tid;
|
|
*block = transaction->t_log_start;
|
|
} else if ((transaction = journal->j_committing_transaction) != NULL) {
|
|
*tid = transaction->t_tid;
|
|
*block = transaction->t_log_start;
|
|
} else if ((transaction = journal->j_running_transaction) != NULL) {
|
|
*tid = transaction->t_tid;
|
|
*block = journal->j_head;
|
|
} else {
|
|
*tid = journal->j_transaction_sequence;
|
|
*block = journal->j_head;
|
|
}
|
|
ret = tid_gt(*tid, journal->j_tail_sequence);
|
|
spin_unlock(&journal->j_list_lock);
|
|
read_unlock(&journal->j_state_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Update information in journal structure and in on disk journal superblock
|
|
* about log tail. This function does not check whether information passed in
|
|
* really pushes log tail further. It's responsibility of the caller to make
|
|
* sure provided log tail information is valid (e.g. by holding
|
|
* j_checkpoint_mutex all the time between computing log tail and calling this
|
|
* function as is the case with jbd2_cleanup_journal_tail()).
|
|
*
|
|
* Requires j_checkpoint_mutex
|
|
*/
|
|
int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block)
|
|
{
|
|
unsigned long freed;
|
|
int ret;
|
|
|
|
BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex));
|
|
|
|
/*
|
|
* We cannot afford for write to remain in drive's caches since as
|
|
* soon as we update j_tail, next transaction can start reusing journal
|
|
* space and if we lose sb update during power failure we'd replay
|
|
* old transaction with possibly newly overwritten data.
|
|
*/
|
|
ret = jbd2_journal_update_sb_log_tail(journal, tid, block,
|
|
REQ_SYNC | REQ_FUA);
|
|
if (ret)
|
|
goto out;
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
freed = block - journal->j_tail;
|
|
if (block < journal->j_tail)
|
|
freed += journal->j_last - journal->j_first;
|
|
|
|
trace_jbd2_update_log_tail(journal, tid, block, freed);
|
|
jbd_debug(1,
|
|
"Cleaning journal tail from %u to %u (offset %lu), "
|
|
"freeing %lu\n",
|
|
journal->j_tail_sequence, tid, block, freed);
|
|
|
|
journal->j_free += freed;
|
|
journal->j_tail_sequence = tid;
|
|
journal->j_tail = block;
|
|
write_unlock(&journal->j_state_lock);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* This is a variation of __jbd2_update_log_tail which checks for validity of
|
|
* provided log tail and locks j_checkpoint_mutex. So it is safe against races
|
|
* with other threads updating log tail.
|
|
*/
|
|
void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block)
|
|
{
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
if (tid_gt(tid, journal->j_tail_sequence))
|
|
__jbd2_update_log_tail(journal, tid, block);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
}
|
|
|
|
struct jbd2_stats_proc_session {
|
|
journal_t *journal;
|
|
struct transaction_stats_s *stats;
|
|
int start;
|
|
int max;
|
|
};
|
|
|
|
static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
return *pos ? NULL : SEQ_START_TOKEN;
|
|
}
|
|
|
|
static void *jbd2_seq_info_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
(*pos)++;
|
|
return NULL;
|
|
}
|
|
|
|
static int jbd2_seq_info_show(struct seq_file *seq, void *v)
|
|
{
|
|
struct jbd2_stats_proc_session *s = seq->private;
|
|
|
|
if (v != SEQ_START_TOKEN)
|
|
return 0;
|
|
seq_printf(seq, "%lu transactions (%lu requested), "
|
|
"each up to %u blocks\n",
|
|
s->stats->ts_tid, s->stats->ts_requested,
|
|
s->journal->j_max_transaction_buffers);
|
|
if (s->stats->ts_tid == 0)
|
|
return 0;
|
|
seq_printf(seq, "average: \n %ums waiting for transaction\n",
|
|
jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid));
|
|
seq_printf(seq, " %ums request delay\n",
|
|
(s->stats->ts_requested == 0) ? 0 :
|
|
jiffies_to_msecs(s->stats->run.rs_request_delay /
|
|
s->stats->ts_requested));
|
|
seq_printf(seq, " %ums running transaction\n",
|
|
jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid));
|
|
seq_printf(seq, " %ums transaction was being locked\n",
|
|
jiffies_to_msecs(s->stats->run.rs_locked / s->stats->ts_tid));
|
|
seq_printf(seq, " %ums flushing data (in ordered mode)\n",
|
|
jiffies_to_msecs(s->stats->run.rs_flushing / s->stats->ts_tid));
|
|
seq_printf(seq, " %ums logging transaction\n",
|
|
jiffies_to_msecs(s->stats->run.rs_logging / s->stats->ts_tid));
|
|
seq_printf(seq, " %lluus average transaction commit time\n",
|
|
div_u64(s->journal->j_average_commit_time, 1000));
|
|
seq_printf(seq, " %lu handles per transaction\n",
|
|
s->stats->run.rs_handle_count / s->stats->ts_tid);
|
|
seq_printf(seq, " %lu blocks per transaction\n",
|
|
s->stats->run.rs_blocks / s->stats->ts_tid);
|
|
seq_printf(seq, " %lu logged blocks per transaction\n",
|
|
s->stats->run.rs_blocks_logged / s->stats->ts_tid);
|
|
return 0;
|
|
}
|
|
|
|
static void jbd2_seq_info_stop(struct seq_file *seq, void *v)
|
|
{
|
|
}
|
|
|
|
static const struct seq_operations jbd2_seq_info_ops = {
|
|
.start = jbd2_seq_info_start,
|
|
.next = jbd2_seq_info_next,
|
|
.stop = jbd2_seq_info_stop,
|
|
.show = jbd2_seq_info_show,
|
|
};
|
|
|
|
static int jbd2_seq_info_open(struct inode *inode, struct file *file)
|
|
{
|
|
journal_t *journal = PDE_DATA(inode);
|
|
struct jbd2_stats_proc_session *s;
|
|
int rc, size;
|
|
|
|
s = kmalloc(sizeof(*s), GFP_KERNEL);
|
|
if (s == NULL)
|
|
return -ENOMEM;
|
|
size = sizeof(struct transaction_stats_s);
|
|
s->stats = kmalloc(size, GFP_KERNEL);
|
|
if (s->stats == NULL) {
|
|
kfree(s);
|
|
return -ENOMEM;
|
|
}
|
|
spin_lock(&journal->j_history_lock);
|
|
memcpy(s->stats, &journal->j_stats, size);
|
|
s->journal = journal;
|
|
spin_unlock(&journal->j_history_lock);
|
|
|
|
rc = seq_open(file, &jbd2_seq_info_ops);
|
|
if (rc == 0) {
|
|
struct seq_file *m = file->private_data;
|
|
m->private = s;
|
|
} else {
|
|
kfree(s->stats);
|
|
kfree(s);
|
|
}
|
|
return rc;
|
|
|
|
}
|
|
|
|
static int jbd2_seq_info_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct seq_file *seq = file->private_data;
|
|
struct jbd2_stats_proc_session *s = seq->private;
|
|
kfree(s->stats);
|
|
kfree(s);
|
|
return seq_release(inode, file);
|
|
}
|
|
|
|
static const struct proc_ops jbd2_info_proc_ops = {
|
|
.proc_open = jbd2_seq_info_open,
|
|
.proc_read = seq_read,
|
|
.proc_lseek = seq_lseek,
|
|
.proc_release = jbd2_seq_info_release,
|
|
};
|
|
|
|
static struct proc_dir_entry *proc_jbd2_stats;
|
|
|
|
static void jbd2_stats_proc_init(journal_t *journal)
|
|
{
|
|
journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats);
|
|
if (journal->j_proc_entry) {
|
|
proc_create_data("info", S_IRUGO, journal->j_proc_entry,
|
|
&jbd2_info_proc_ops, journal);
|
|
}
|
|
}
|
|
|
|
static void jbd2_stats_proc_exit(journal_t *journal)
|
|
{
|
|
remove_proc_entry("info", journal->j_proc_entry);
|
|
remove_proc_entry(journal->j_devname, proc_jbd2_stats);
|
|
}
|
|
|
|
/* Minimum size of descriptor tag */
|
|
static int jbd2_min_tag_size(void)
|
|
{
|
|
/*
|
|
* Tag with 32-bit block numbers does not use last four bytes of the
|
|
* structure
|
|
*/
|
|
return sizeof(journal_block_tag_t) - 4;
|
|
}
|
|
|
|
/*
|
|
* Management for journal control blocks: functions to create and
|
|
* destroy journal_t structures, and to initialise and read existing
|
|
* journal blocks from disk. */
|
|
|
|
/* First: create and setup a journal_t object in memory. We initialise
|
|
* very few fields yet: that has to wait until we have created the
|
|
* journal structures from from scratch, or loaded them from disk. */
|
|
|
|
static journal_t *journal_init_common(struct block_device *bdev,
|
|
struct block_device *fs_dev,
|
|
unsigned long long start, int len, int blocksize)
|
|
{
|
|
static struct lock_class_key jbd2_trans_commit_key;
|
|
journal_t *journal;
|
|
int err;
|
|
struct buffer_head *bh;
|
|
int n;
|
|
|
|
journal = kzalloc(sizeof(*journal), GFP_KERNEL);
|
|
if (!journal)
|
|
return NULL;
|
|
|
|
init_waitqueue_head(&journal->j_wait_transaction_locked);
|
|
init_waitqueue_head(&journal->j_wait_done_commit);
|
|
init_waitqueue_head(&journal->j_wait_commit);
|
|
init_waitqueue_head(&journal->j_wait_updates);
|
|
init_waitqueue_head(&journal->j_wait_reserved);
|
|
mutex_init(&journal->j_abort_mutex);
|
|
mutex_init(&journal->j_barrier);
|
|
mutex_init(&journal->j_checkpoint_mutex);
|
|
spin_lock_init(&journal->j_revoke_lock);
|
|
spin_lock_init(&journal->j_list_lock);
|
|
rwlock_init(&journal->j_state_lock);
|
|
|
|
journal->j_commit_interval = (HZ * JBD2_DEFAULT_MAX_COMMIT_AGE);
|
|
journal->j_min_batch_time = 0;
|
|
journal->j_max_batch_time = 15000; /* 15ms */
|
|
atomic_set(&journal->j_reserved_credits, 0);
|
|
|
|
/* The journal is marked for error until we succeed with recovery! */
|
|
journal->j_flags = JBD2_ABORT;
|
|
|
|
/* Set up a default-sized revoke table for the new mount. */
|
|
err = jbd2_journal_init_revoke(journal, JOURNAL_REVOKE_DEFAULT_HASH);
|
|
if (err)
|
|
goto err_cleanup;
|
|
|
|
spin_lock_init(&journal->j_history_lock);
|
|
|
|
lockdep_init_map(&journal->j_trans_commit_map, "jbd2_handle",
|
|
&jbd2_trans_commit_key, 0);
|
|
|
|
/* journal descriptor can store up to n blocks -bzzz */
|
|
journal->j_blocksize = blocksize;
|
|
journal->j_dev = bdev;
|
|
journal->j_fs_dev = fs_dev;
|
|
journal->j_blk_offset = start;
|
|
journal->j_maxlen = len;
|
|
/* We need enough buffers to write out full descriptor block. */
|
|
n = journal->j_blocksize / jbd2_min_tag_size();
|
|
journal->j_wbufsize = n;
|
|
journal->j_wbuf = kmalloc_array(n, sizeof(struct buffer_head *),
|
|
GFP_KERNEL);
|
|
if (!journal->j_wbuf)
|
|
goto err_cleanup;
|
|
|
|
bh = getblk_unmovable(journal->j_dev, start, journal->j_blocksize);
|
|
if (!bh) {
|
|
pr_err("%s: Cannot get buffer for journal superblock\n",
|
|
__func__);
|
|
goto err_cleanup;
|
|
}
|
|
journal->j_sb_buffer = bh;
|
|
journal->j_superblock = (journal_superblock_t *)bh->b_data;
|
|
|
|
return journal;
|
|
|
|
err_cleanup:
|
|
kfree(journal->j_wbuf);
|
|
jbd2_journal_destroy_revoke(journal);
|
|
kfree(journal);
|
|
return NULL;
|
|
}
|
|
|
|
/* jbd2_journal_init_dev and jbd2_journal_init_inode:
|
|
*
|
|
* Create a journal structure assigned some fixed set of disk blocks to
|
|
* the journal. We don't actually touch those disk blocks yet, but we
|
|
* need to set up all of the mapping information to tell the journaling
|
|
* system where the journal blocks are.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* journal_t * jbd2_journal_init_dev() - creates and initialises a journal structure
|
|
* @bdev: Block device on which to create the journal
|
|
* @fs_dev: Device which hold journalled filesystem for this journal.
|
|
* @start: Block nr Start of journal.
|
|
* @len: Length of the journal in blocks.
|
|
* @blocksize: blocksize of journalling device
|
|
*
|
|
* Returns: a newly created journal_t *
|
|
*
|
|
* jbd2_journal_init_dev creates a journal which maps a fixed contiguous
|
|
* range of blocks on an arbitrary block device.
|
|
*
|
|
*/
|
|
journal_t *jbd2_journal_init_dev(struct block_device *bdev,
|
|
struct block_device *fs_dev,
|
|
unsigned long long start, int len, int blocksize)
|
|
{
|
|
journal_t *journal;
|
|
|
|
journal = journal_init_common(bdev, fs_dev, start, len, blocksize);
|
|
if (!journal)
|
|
return NULL;
|
|
|
|
bdevname(journal->j_dev, journal->j_devname);
|
|
strreplace(journal->j_devname, '/', '!');
|
|
jbd2_stats_proc_init(journal);
|
|
|
|
return journal;
|
|
}
|
|
|
|
/**
|
|
* journal_t * jbd2_journal_init_inode () - creates a journal which maps to a inode.
|
|
* @inode: An inode to create the journal in
|
|
*
|
|
* jbd2_journal_init_inode creates a journal which maps an on-disk inode as
|
|
* the journal. The inode must exist already, must support bmap() and
|
|
* must have all data blocks preallocated.
|
|
*/
|
|
journal_t *jbd2_journal_init_inode(struct inode *inode)
|
|
{
|
|
journal_t *journal;
|
|
sector_t blocknr;
|
|
char *p;
|
|
int err = 0;
|
|
|
|
blocknr = 0;
|
|
err = bmap(inode, &blocknr);
|
|
|
|
if (err || !blocknr) {
|
|
pr_err("%s: Cannot locate journal superblock\n",
|
|
__func__);
|
|
return NULL;
|
|
}
|
|
|
|
jbd_debug(1, "JBD2: inode %s/%ld, size %lld, bits %d, blksize %ld\n",
|
|
inode->i_sb->s_id, inode->i_ino, (long long) inode->i_size,
|
|
inode->i_sb->s_blocksize_bits, inode->i_sb->s_blocksize);
|
|
|
|
journal = journal_init_common(inode->i_sb->s_bdev, inode->i_sb->s_bdev,
|
|
blocknr, inode->i_size >> inode->i_sb->s_blocksize_bits,
|
|
inode->i_sb->s_blocksize);
|
|
if (!journal)
|
|
return NULL;
|
|
|
|
journal->j_inode = inode;
|
|
bdevname(journal->j_dev, journal->j_devname);
|
|
p = strreplace(journal->j_devname, '/', '!');
|
|
sprintf(p, "-%lu", journal->j_inode->i_ino);
|
|
jbd2_stats_proc_init(journal);
|
|
|
|
return journal;
|
|
}
|
|
|
|
/*
|
|
* If the journal init or create aborts, we need to mark the journal
|
|
* superblock as being NULL to prevent the journal destroy from writing
|
|
* back a bogus superblock.
|
|
*/
|
|
static void journal_fail_superblock (journal_t *journal)
|
|
{
|
|
struct buffer_head *bh = journal->j_sb_buffer;
|
|
brelse(bh);
|
|
journal->j_sb_buffer = NULL;
|
|
}
|
|
|
|
/*
|
|
* Given a journal_t structure, initialise the various fields for
|
|
* startup of a new journaling session. We use this both when creating
|
|
* a journal, and after recovering an old journal to reset it for
|
|
* subsequent use.
|
|
*/
|
|
|
|
static int journal_reset(journal_t *journal)
|
|
{
|
|
journal_superblock_t *sb = journal->j_superblock;
|
|
unsigned long long first, last;
|
|
|
|
first = be32_to_cpu(sb->s_first);
|
|
last = be32_to_cpu(sb->s_maxlen);
|
|
if (first + JBD2_MIN_JOURNAL_BLOCKS > last + 1) {
|
|
printk(KERN_ERR "JBD2: Journal too short (blocks %llu-%llu).\n",
|
|
first, last);
|
|
journal_fail_superblock(journal);
|
|
return -EINVAL;
|
|
}
|
|
|
|
journal->j_first = first;
|
|
journal->j_last = last;
|
|
|
|
journal->j_head = first;
|
|
journal->j_tail = first;
|
|
journal->j_free = last - first;
|
|
|
|
journal->j_tail_sequence = journal->j_transaction_sequence;
|
|
journal->j_commit_sequence = journal->j_transaction_sequence - 1;
|
|
journal->j_commit_request = journal->j_commit_sequence;
|
|
|
|
journal->j_max_transaction_buffers = journal->j_maxlen / 4;
|
|
|
|
/*
|
|
* As a special case, if the on-disk copy is already marked as needing
|
|
* no recovery (s_start == 0), then we can safely defer the superblock
|
|
* update until the next commit by setting JBD2_FLUSHED. This avoids
|
|
* attempting a write to a potential-readonly device.
|
|
*/
|
|
if (sb->s_start == 0) {
|
|
jbd_debug(1, "JBD2: Skipping superblock update on recovered sb "
|
|
"(start %ld, seq %u, errno %d)\n",
|
|
journal->j_tail, journal->j_tail_sequence,
|
|
journal->j_errno);
|
|
journal->j_flags |= JBD2_FLUSHED;
|
|
} else {
|
|
/* Lock here to make assertions happy... */
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
/*
|
|
* Update log tail information. We use REQ_FUA since new
|
|
* transaction will start reusing journal space and so we
|
|
* must make sure information about current log tail is on
|
|
* disk before that.
|
|
*/
|
|
jbd2_journal_update_sb_log_tail(journal,
|
|
journal->j_tail_sequence,
|
|
journal->j_tail,
|
|
REQ_SYNC | REQ_FUA);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
}
|
|
return jbd2_journal_start_thread(journal);
|
|
}
|
|
|
|
/*
|
|
* This function expects that the caller will have locked the journal
|
|
* buffer head, and will return with it unlocked
|
|
*/
|
|
static int jbd2_write_superblock(journal_t *journal, int write_flags)
|
|
{
|
|
struct buffer_head *bh = journal->j_sb_buffer;
|
|
journal_superblock_t *sb = journal->j_superblock;
|
|
int ret;
|
|
|
|
/* Buffer got discarded which means block device got invalidated */
|
|
if (!buffer_mapped(bh))
|
|
return -EIO;
|
|
|
|
trace_jbd2_write_superblock(journal, write_flags);
|
|
if (!(journal->j_flags & JBD2_BARRIER))
|
|
write_flags &= ~(REQ_FUA | REQ_PREFLUSH);
|
|
if (buffer_write_io_error(bh)) {
|
|
/*
|
|
* Oh, dear. A previous attempt to write the journal
|
|
* superblock failed. This could happen because the
|
|
* USB device was yanked out. Or it could happen to
|
|
* be a transient write error and maybe the block will
|
|
* be remapped. Nothing we can do but to retry the
|
|
* write and hope for the best.
|
|
*/
|
|
printk(KERN_ERR "JBD2: previous I/O error detected "
|
|
"for journal superblock update for %s.\n",
|
|
journal->j_devname);
|
|
clear_buffer_write_io_error(bh);
|
|
set_buffer_uptodate(bh);
|
|
}
|
|
if (jbd2_journal_has_csum_v2or3(journal))
|
|
sb->s_checksum = jbd2_superblock_csum(journal, sb);
|
|
get_bh(bh);
|
|
bh->b_end_io = end_buffer_write_sync;
|
|
ret = submit_bh(REQ_OP_WRITE, write_flags, bh);
|
|
wait_on_buffer(bh);
|
|
if (buffer_write_io_error(bh)) {
|
|
clear_buffer_write_io_error(bh);
|
|
set_buffer_uptodate(bh);
|
|
ret = -EIO;
|
|
}
|
|
if (ret) {
|
|
printk(KERN_ERR "JBD2: Error %d detected when updating "
|
|
"journal superblock for %s.\n", ret,
|
|
journal->j_devname);
|
|
if (!is_journal_aborted(journal))
|
|
jbd2_journal_abort(journal, ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* jbd2_journal_update_sb_log_tail() - Update log tail in journal sb on disk.
|
|
* @journal: The journal to update.
|
|
* @tail_tid: TID of the new transaction at the tail of the log
|
|
* @tail_block: The first block of the transaction at the tail of the log
|
|
* @write_op: With which operation should we write the journal sb
|
|
*
|
|
* Update a journal's superblock information about log tail and write it to
|
|
* disk, waiting for the IO to complete.
|
|
*/
|
|
int jbd2_journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid,
|
|
unsigned long tail_block, int write_op)
|
|
{
|
|
journal_superblock_t *sb = journal->j_superblock;
|
|
int ret;
|
|
|
|
if (is_journal_aborted(journal))
|
|
return -EIO;
|
|
|
|
BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex));
|
|
jbd_debug(1, "JBD2: updating superblock (start %lu, seq %u)\n",
|
|
tail_block, tail_tid);
|
|
|
|
lock_buffer(journal->j_sb_buffer);
|
|
sb->s_sequence = cpu_to_be32(tail_tid);
|
|
sb->s_start = cpu_to_be32(tail_block);
|
|
|
|
ret = jbd2_write_superblock(journal, write_op);
|
|
if (ret)
|
|
goto out;
|
|
|
|
/* Log is no longer empty */
|
|
write_lock(&journal->j_state_lock);
|
|
WARN_ON(!sb->s_sequence);
|
|
journal->j_flags &= ~JBD2_FLUSHED;
|
|
write_unlock(&journal->j_state_lock);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* jbd2_mark_journal_empty() - Mark on disk journal as empty.
|
|
* @journal: The journal to update.
|
|
* @write_op: With which operation should we write the journal sb
|
|
*
|
|
* Update a journal's dynamic superblock fields to show that journal is empty.
|
|
* Write updated superblock to disk waiting for IO to complete.
|
|
*/
|
|
static void jbd2_mark_journal_empty(journal_t *journal, int write_op)
|
|
{
|
|
journal_superblock_t *sb = journal->j_superblock;
|
|
|
|
BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex));
|
|
lock_buffer(journal->j_sb_buffer);
|
|
if (sb->s_start == 0) { /* Is it already empty? */
|
|
unlock_buffer(journal->j_sb_buffer);
|
|
return;
|
|
}
|
|
|
|
jbd_debug(1, "JBD2: Marking journal as empty (seq %u)\n",
|
|
journal->j_tail_sequence);
|
|
|
|
sb->s_sequence = cpu_to_be32(journal->j_tail_sequence);
|
|
sb->s_start = cpu_to_be32(0);
|
|
|
|
jbd2_write_superblock(journal, write_op);
|
|
|
|
/* Log is no longer empty */
|
|
write_lock(&journal->j_state_lock);
|
|
journal->j_flags |= JBD2_FLUSHED;
|
|
write_unlock(&journal->j_state_lock);
|
|
}
|
|
|
|
|
|
/**
|
|
* jbd2_journal_update_sb_errno() - Update error in the journal.
|
|
* @journal: The journal to update.
|
|
*
|
|
* Update a journal's errno. Write updated superblock to disk waiting for IO
|
|
* to complete.
|
|
*/
|
|
void jbd2_journal_update_sb_errno(journal_t *journal)
|
|
{
|
|
journal_superblock_t *sb = journal->j_superblock;
|
|
int errcode;
|
|
|
|
lock_buffer(journal->j_sb_buffer);
|
|
errcode = journal->j_errno;
|
|
if (errcode == -ESHUTDOWN)
|
|
errcode = 0;
|
|
jbd_debug(1, "JBD2: updating superblock error (errno %d)\n", errcode);
|
|
sb->s_errno = cpu_to_be32(errcode);
|
|
|
|
jbd2_write_superblock(journal, REQ_SYNC | REQ_FUA);
|
|
}
|
|
EXPORT_SYMBOL(jbd2_journal_update_sb_errno);
|
|
|
|
static int journal_revoke_records_per_block(journal_t *journal)
|
|
{
|
|
int record_size;
|
|
int space = journal->j_blocksize - sizeof(jbd2_journal_revoke_header_t);
|
|
|
|
if (jbd2_has_feature_64bit(journal))
|
|
record_size = 8;
|
|
else
|
|
record_size = 4;
|
|
|
|
if (jbd2_journal_has_csum_v2or3(journal))
|
|
space -= sizeof(struct jbd2_journal_block_tail);
|
|
return space / record_size;
|
|
}
|
|
|
|
/*
|
|
* Read the superblock for a given journal, performing initial
|
|
* validation of the format.
|
|
*/
|
|
static int journal_get_superblock(journal_t *journal)
|
|
{
|
|
struct buffer_head *bh;
|
|
journal_superblock_t *sb;
|
|
int err = -EIO;
|
|
|
|
bh = journal->j_sb_buffer;
|
|
|
|
J_ASSERT(bh != NULL);
|
|
if (!buffer_uptodate(bh)) {
|
|
ll_rw_block(REQ_OP_READ, 0, 1, &bh);
|
|
wait_on_buffer(bh);
|
|
if (!buffer_uptodate(bh)) {
|
|
printk(KERN_ERR
|
|
"JBD2: IO error reading journal superblock\n");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (buffer_verified(bh))
|
|
return 0;
|
|
|
|
sb = journal->j_superblock;
|
|
|
|
err = -EINVAL;
|
|
|
|
if (sb->s_header.h_magic != cpu_to_be32(JBD2_MAGIC_NUMBER) ||
|
|
sb->s_blocksize != cpu_to_be32(journal->j_blocksize)) {
|
|
printk(KERN_WARNING "JBD2: no valid journal superblock found\n");
|
|
goto out;
|
|
}
|
|
|
|
switch(be32_to_cpu(sb->s_header.h_blocktype)) {
|
|
case JBD2_SUPERBLOCK_V1:
|
|
journal->j_format_version = 1;
|
|
break;
|
|
case JBD2_SUPERBLOCK_V2:
|
|
journal->j_format_version = 2;
|
|
break;
|
|
default:
|
|
printk(KERN_WARNING "JBD2: unrecognised superblock format ID\n");
|
|
goto out;
|
|
}
|
|
|
|
if (be32_to_cpu(sb->s_maxlen) < journal->j_maxlen)
|
|
journal->j_maxlen = be32_to_cpu(sb->s_maxlen);
|
|
else if (be32_to_cpu(sb->s_maxlen) > journal->j_maxlen) {
|
|
printk(KERN_WARNING "JBD2: journal file too short\n");
|
|
goto out;
|
|
}
|
|
|
|
if (be32_to_cpu(sb->s_first) == 0 ||
|
|
be32_to_cpu(sb->s_first) >= journal->j_maxlen) {
|
|
printk(KERN_WARNING
|
|
"JBD2: Invalid start block of journal: %u\n",
|
|
be32_to_cpu(sb->s_first));
|
|
goto out;
|
|
}
|
|
|
|
if (jbd2_has_feature_csum2(journal) &&
|
|
jbd2_has_feature_csum3(journal)) {
|
|
/* Can't have checksum v2 and v3 at the same time! */
|
|
printk(KERN_ERR "JBD2: Can't enable checksumming v2 and v3 "
|
|
"at the same time!\n");
|
|
goto out;
|
|
}
|
|
|
|
if (jbd2_journal_has_csum_v2or3_feature(journal) &&
|
|
jbd2_has_feature_checksum(journal)) {
|
|
/* Can't have checksum v1 and v2 on at the same time! */
|
|
printk(KERN_ERR "JBD2: Can't enable checksumming v1 and v2/3 "
|
|
"at the same time!\n");
|
|
goto out;
|
|
}
|
|
|
|
if (!jbd2_verify_csum_type(journal, sb)) {
|
|
printk(KERN_ERR "JBD2: Unknown checksum type\n");
|
|
goto out;
|
|
}
|
|
|
|
/* Load the checksum driver */
|
|
if (jbd2_journal_has_csum_v2or3_feature(journal)) {
|
|
journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
|
|
if (IS_ERR(journal->j_chksum_driver)) {
|
|
printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n");
|
|
err = PTR_ERR(journal->j_chksum_driver);
|
|
journal->j_chksum_driver = NULL;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (jbd2_journal_has_csum_v2or3(journal)) {
|
|
/* Check superblock checksum */
|
|
if (sb->s_checksum != jbd2_superblock_csum(journal, sb)) {
|
|
printk(KERN_ERR "JBD2: journal checksum error\n");
|
|
err = -EFSBADCRC;
|
|
goto out;
|
|
}
|
|
|
|
/* Precompute checksum seed for all metadata */
|
|
journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,
|
|
sizeof(sb->s_uuid));
|
|
}
|
|
|
|
journal->j_revoke_records_per_block =
|
|
journal_revoke_records_per_block(journal);
|
|
set_buffer_verified(bh);
|
|
|
|
return 0;
|
|
|
|
out:
|
|
journal_fail_superblock(journal);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Load the on-disk journal superblock and read the key fields into the
|
|
* journal_t.
|
|
*/
|
|
|
|
static int load_superblock(journal_t *journal)
|
|
{
|
|
int err;
|
|
journal_superblock_t *sb;
|
|
|
|
err = journal_get_superblock(journal);
|
|
if (err)
|
|
return err;
|
|
|
|
sb = journal->j_superblock;
|
|
|
|
journal->j_tail_sequence = be32_to_cpu(sb->s_sequence);
|
|
journal->j_tail = be32_to_cpu(sb->s_start);
|
|
journal->j_first = be32_to_cpu(sb->s_first);
|
|
journal->j_last = be32_to_cpu(sb->s_maxlen);
|
|
journal->j_errno = be32_to_cpu(sb->s_errno);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* int jbd2_journal_load() - Read journal from disk.
|
|
* @journal: Journal to act on.
|
|
*
|
|
* Given a journal_t structure which tells us which disk blocks contain
|
|
* a journal, read the journal from disk to initialise the in-memory
|
|
* structures.
|
|
*/
|
|
int jbd2_journal_load(journal_t *journal)
|
|
{
|
|
int err;
|
|
journal_superblock_t *sb;
|
|
|
|
err = load_superblock(journal);
|
|
if (err)
|
|
return err;
|
|
|
|
sb = journal->j_superblock;
|
|
/* If this is a V2 superblock, then we have to check the
|
|
* features flags on it. */
|
|
|
|
if (journal->j_format_version >= 2) {
|
|
if ((sb->s_feature_ro_compat &
|
|
~cpu_to_be32(JBD2_KNOWN_ROCOMPAT_FEATURES)) ||
|
|
(sb->s_feature_incompat &
|
|
~cpu_to_be32(JBD2_KNOWN_INCOMPAT_FEATURES))) {
|
|
printk(KERN_WARNING
|
|
"JBD2: Unrecognised features on journal\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Create a slab for this blocksize
|
|
*/
|
|
err = jbd2_journal_create_slab(be32_to_cpu(sb->s_blocksize));
|
|
if (err)
|
|
return err;
|
|
|
|
/* Let the recovery code check whether it needs to recover any
|
|
* data from the journal. */
|
|
if (jbd2_journal_recover(journal))
|
|
goto recovery_error;
|
|
|
|
if (journal->j_failed_commit) {
|
|
printk(KERN_ERR "JBD2: journal transaction %u on %s "
|
|
"is corrupt.\n", journal->j_failed_commit,
|
|
journal->j_devname);
|
|
return -EFSCORRUPTED;
|
|
}
|
|
/*
|
|
* clear JBD2_ABORT flag initialized in journal_init_common
|
|
* here to update log tail information with the newest seq.
|
|
*/
|
|
journal->j_flags &= ~JBD2_ABORT;
|
|
|
|
/* OK, we've finished with the dynamic journal bits:
|
|
* reinitialise the dynamic contents of the superblock in memory
|
|
* and reset them on disk. */
|
|
if (journal_reset(journal))
|
|
goto recovery_error;
|
|
|
|
journal->j_flags |= JBD2_LOADED;
|
|
return 0;
|
|
|
|
recovery_error:
|
|
printk(KERN_WARNING "JBD2: recovery failed\n");
|
|
return -EIO;
|
|
}
|
|
|
|
/**
|
|
* void jbd2_journal_destroy() - Release a journal_t structure.
|
|
* @journal: Journal to act on.
|
|
*
|
|
* Release a journal_t structure once it is no longer in use by the
|
|
* journaled object.
|
|
* Return <0 if we couldn't clean up the journal.
|
|
*/
|
|
int jbd2_journal_destroy(journal_t *journal)
|
|
{
|
|
int err = 0;
|
|
|
|
/* Wait for the commit thread to wake up and die. */
|
|
journal_kill_thread(journal);
|
|
|
|
/* Force a final log commit */
|
|
if (journal->j_running_transaction)
|
|
jbd2_journal_commit_transaction(journal);
|
|
|
|
/* Force any old transactions to disk */
|
|
|
|
/* Totally anal locking here... */
|
|
spin_lock(&journal->j_list_lock);
|
|
while (journal->j_checkpoint_transactions != NULL) {
|
|
spin_unlock(&journal->j_list_lock);
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
err = jbd2_log_do_checkpoint(journal);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
/*
|
|
* If checkpointing failed, just free the buffers to avoid
|
|
* looping forever
|
|
*/
|
|
if (err) {
|
|
jbd2_journal_destroy_checkpoint(journal);
|
|
spin_lock(&journal->j_list_lock);
|
|
break;
|
|
}
|
|
spin_lock(&journal->j_list_lock);
|
|
}
|
|
|
|
J_ASSERT(journal->j_running_transaction == NULL);
|
|
J_ASSERT(journal->j_committing_transaction == NULL);
|
|
J_ASSERT(journal->j_checkpoint_transactions == NULL);
|
|
spin_unlock(&journal->j_list_lock);
|
|
|
|
if (journal->j_sb_buffer) {
|
|
if (!is_journal_aborted(journal)) {
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
journal->j_tail_sequence =
|
|
++journal->j_transaction_sequence;
|
|
write_unlock(&journal->j_state_lock);
|
|
|
|
jbd2_mark_journal_empty(journal,
|
|
REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
} else
|
|
err = -EIO;
|
|
brelse(journal->j_sb_buffer);
|
|
}
|
|
|
|
if (journal->j_proc_entry)
|
|
jbd2_stats_proc_exit(journal);
|
|
iput(journal->j_inode);
|
|
if (journal->j_revoke)
|
|
jbd2_journal_destroy_revoke(journal);
|
|
if (journal->j_chksum_driver)
|
|
crypto_free_shash(journal->j_chksum_driver);
|
|
kfree(journal->j_wbuf);
|
|
kfree(journal);
|
|
|
|
return err;
|
|
}
|
|
|
|
|
|
/**
|
|
*int jbd2_journal_check_used_features () - Check if features specified are used.
|
|
* @journal: Journal to check.
|
|
* @compat: bitmask of compatible features
|
|
* @ro: bitmask of features that force read-only mount
|
|
* @incompat: bitmask of incompatible features
|
|
*
|
|
* Check whether the journal uses all of a given set of
|
|
* features. Return true (non-zero) if it does.
|
|
**/
|
|
|
|
int jbd2_journal_check_used_features (journal_t *journal, unsigned long compat,
|
|
unsigned long ro, unsigned long incompat)
|
|
{
|
|
journal_superblock_t *sb;
|
|
|
|
if (!compat && !ro && !incompat)
|
|
return 1;
|
|
/* Load journal superblock if it is not loaded yet. */
|
|
if (journal->j_format_version == 0 &&
|
|
journal_get_superblock(journal) != 0)
|
|
return 0;
|
|
if (journal->j_format_version == 1)
|
|
return 0;
|
|
|
|
sb = journal->j_superblock;
|
|
|
|
if (((be32_to_cpu(sb->s_feature_compat) & compat) == compat) &&
|
|
((be32_to_cpu(sb->s_feature_ro_compat) & ro) == ro) &&
|
|
((be32_to_cpu(sb->s_feature_incompat) & incompat) == incompat))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* int jbd2_journal_check_available_features() - Check feature set in journalling layer
|
|
* @journal: Journal to check.
|
|
* @compat: bitmask of compatible features
|
|
* @ro: bitmask of features that force read-only mount
|
|
* @incompat: bitmask of incompatible features
|
|
*
|
|
* Check whether the journaling code supports the use of
|
|
* all of a given set of features on this journal. Return true
|
|
* (non-zero) if it can. */
|
|
|
|
int jbd2_journal_check_available_features (journal_t *journal, unsigned long compat,
|
|
unsigned long ro, unsigned long incompat)
|
|
{
|
|
if (!compat && !ro && !incompat)
|
|
return 1;
|
|
|
|
/* We can support any known requested features iff the
|
|
* superblock is in version 2. Otherwise we fail to support any
|
|
* extended sb features. */
|
|
|
|
if (journal->j_format_version != 2)
|
|
return 0;
|
|
|
|
if ((compat & JBD2_KNOWN_COMPAT_FEATURES) == compat &&
|
|
(ro & JBD2_KNOWN_ROCOMPAT_FEATURES) == ro &&
|
|
(incompat & JBD2_KNOWN_INCOMPAT_FEATURES) == incompat)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* int jbd2_journal_set_features () - Mark a given journal feature in the superblock
|
|
* @journal: Journal to act on.
|
|
* @compat: bitmask of compatible features
|
|
* @ro: bitmask of features that force read-only mount
|
|
* @incompat: bitmask of incompatible features
|
|
*
|
|
* Mark a given journal feature as present on the
|
|
* superblock. Returns true if the requested features could be set.
|
|
*
|
|
*/
|
|
|
|
int jbd2_journal_set_features (journal_t *journal, unsigned long compat,
|
|
unsigned long ro, unsigned long incompat)
|
|
{
|
|
#define INCOMPAT_FEATURE_ON(f) \
|
|
((incompat & (f)) && !(sb->s_feature_incompat & cpu_to_be32(f)))
|
|
#define COMPAT_FEATURE_ON(f) \
|
|
((compat & (f)) && !(sb->s_feature_compat & cpu_to_be32(f)))
|
|
journal_superblock_t *sb;
|
|
|
|
if (jbd2_journal_check_used_features(journal, compat, ro, incompat))
|
|
return 1;
|
|
|
|
if (!jbd2_journal_check_available_features(journal, compat, ro, incompat))
|
|
return 0;
|
|
|
|
/* If enabling v2 checksums, turn on v3 instead */
|
|
if (incompat & JBD2_FEATURE_INCOMPAT_CSUM_V2) {
|
|
incompat &= ~JBD2_FEATURE_INCOMPAT_CSUM_V2;
|
|
incompat |= JBD2_FEATURE_INCOMPAT_CSUM_V3;
|
|
}
|
|
|
|
/* Asking for checksumming v3 and v1? Only give them v3. */
|
|
if (incompat & JBD2_FEATURE_INCOMPAT_CSUM_V3 &&
|
|
compat & JBD2_FEATURE_COMPAT_CHECKSUM)
|
|
compat &= ~JBD2_FEATURE_COMPAT_CHECKSUM;
|
|
|
|
jbd_debug(1, "Setting new features 0x%lx/0x%lx/0x%lx\n",
|
|
compat, ro, incompat);
|
|
|
|
sb = journal->j_superblock;
|
|
|
|
/* Load the checksum driver if necessary */
|
|
if ((journal->j_chksum_driver == NULL) &&
|
|
INCOMPAT_FEATURE_ON(JBD2_FEATURE_INCOMPAT_CSUM_V3)) {
|
|
journal->j_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
|
|
if (IS_ERR(journal->j_chksum_driver)) {
|
|
printk(KERN_ERR "JBD2: Cannot load crc32c driver.\n");
|
|
journal->j_chksum_driver = NULL;
|
|
return 0;
|
|
}
|
|
/* Precompute checksum seed for all metadata */
|
|
journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,
|
|
sizeof(sb->s_uuid));
|
|
}
|
|
|
|
lock_buffer(journal->j_sb_buffer);
|
|
|
|
/* If enabling v3 checksums, update superblock */
|
|
if (INCOMPAT_FEATURE_ON(JBD2_FEATURE_INCOMPAT_CSUM_V3)) {
|
|
sb->s_checksum_type = JBD2_CRC32C_CHKSUM;
|
|
sb->s_feature_compat &=
|
|
~cpu_to_be32(JBD2_FEATURE_COMPAT_CHECKSUM);
|
|
}
|
|
|
|
/* If enabling v1 checksums, downgrade superblock */
|
|
if (COMPAT_FEATURE_ON(JBD2_FEATURE_COMPAT_CHECKSUM))
|
|
sb->s_feature_incompat &=
|
|
~cpu_to_be32(JBD2_FEATURE_INCOMPAT_CSUM_V2 |
|
|
JBD2_FEATURE_INCOMPAT_CSUM_V3);
|
|
|
|
sb->s_feature_compat |= cpu_to_be32(compat);
|
|
sb->s_feature_ro_compat |= cpu_to_be32(ro);
|
|
sb->s_feature_incompat |= cpu_to_be32(incompat);
|
|
unlock_buffer(journal->j_sb_buffer);
|
|
journal->j_revoke_records_per_block =
|
|
journal_revoke_records_per_block(journal);
|
|
|
|
return 1;
|
|
#undef COMPAT_FEATURE_ON
|
|
#undef INCOMPAT_FEATURE_ON
|
|
}
|
|
|
|
/*
|
|
* jbd2_journal_clear_features () - Clear a given journal feature in the
|
|
* superblock
|
|
* @journal: Journal to act on.
|
|
* @compat: bitmask of compatible features
|
|
* @ro: bitmask of features that force read-only mount
|
|
* @incompat: bitmask of incompatible features
|
|
*
|
|
* Clear a given journal feature as present on the
|
|
* superblock.
|
|
*/
|
|
void jbd2_journal_clear_features(journal_t *journal, unsigned long compat,
|
|
unsigned long ro, unsigned long incompat)
|
|
{
|
|
journal_superblock_t *sb;
|
|
|
|
jbd_debug(1, "Clear features 0x%lx/0x%lx/0x%lx\n",
|
|
compat, ro, incompat);
|
|
|
|
sb = journal->j_superblock;
|
|
|
|
sb->s_feature_compat &= ~cpu_to_be32(compat);
|
|
sb->s_feature_ro_compat &= ~cpu_to_be32(ro);
|
|
sb->s_feature_incompat &= ~cpu_to_be32(incompat);
|
|
journal->j_revoke_records_per_block =
|
|
journal_revoke_records_per_block(journal);
|
|
}
|
|
EXPORT_SYMBOL(jbd2_journal_clear_features);
|
|
|
|
/**
|
|
* int jbd2_journal_flush () - Flush journal
|
|
* @journal: Journal to act on.
|
|
*
|
|
* Flush all data for a given journal to disk and empty the journal.
|
|
* Filesystems can use this when remounting readonly to ensure that
|
|
* recovery does not need to happen on remount.
|
|
*/
|
|
|
|
int jbd2_journal_flush(journal_t *journal)
|
|
{
|
|
int err = 0;
|
|
transaction_t *transaction = NULL;
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
|
|
/* Force everything buffered to the log... */
|
|
if (journal->j_running_transaction) {
|
|
transaction = journal->j_running_transaction;
|
|
__jbd2_log_start_commit(journal, transaction->t_tid);
|
|
} else if (journal->j_committing_transaction)
|
|
transaction = journal->j_committing_transaction;
|
|
|
|
/* Wait for the log commit to complete... */
|
|
if (transaction) {
|
|
tid_t tid = transaction->t_tid;
|
|
|
|
write_unlock(&journal->j_state_lock);
|
|
jbd2_log_wait_commit(journal, tid);
|
|
} else {
|
|
write_unlock(&journal->j_state_lock);
|
|
}
|
|
|
|
/* ...and flush everything in the log out to disk. */
|
|
spin_lock(&journal->j_list_lock);
|
|
while (!err && journal->j_checkpoint_transactions != NULL) {
|
|
spin_unlock(&journal->j_list_lock);
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
err = jbd2_log_do_checkpoint(journal);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
spin_lock(&journal->j_list_lock);
|
|
}
|
|
spin_unlock(&journal->j_list_lock);
|
|
|
|
if (is_journal_aborted(journal))
|
|
return -EIO;
|
|
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
if (!err) {
|
|
err = jbd2_cleanup_journal_tail(journal);
|
|
if (err < 0) {
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
goto out;
|
|
}
|
|
err = 0;
|
|
}
|
|
|
|
/* Finally, mark the journal as really needing no recovery.
|
|
* This sets s_start==0 in the underlying superblock, which is
|
|
* the magic code for a fully-recovered superblock. Any future
|
|
* commits of data to the journal will restore the current
|
|
* s_start value. */
|
|
jbd2_mark_journal_empty(journal, REQ_SYNC | REQ_FUA);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
write_lock(&journal->j_state_lock);
|
|
J_ASSERT(!journal->j_running_transaction);
|
|
J_ASSERT(!journal->j_committing_transaction);
|
|
J_ASSERT(!journal->j_checkpoint_transactions);
|
|
J_ASSERT(journal->j_head == journal->j_tail);
|
|
J_ASSERT(journal->j_tail_sequence == journal->j_transaction_sequence);
|
|
write_unlock(&journal->j_state_lock);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* int jbd2_journal_wipe() - Wipe journal contents
|
|
* @journal: Journal to act on.
|
|
* @write: flag (see below)
|
|
*
|
|
* Wipe out all of the contents of a journal, safely. This will produce
|
|
* a warning if the journal contains any valid recovery information.
|
|
* Must be called between journal_init_*() and jbd2_journal_load().
|
|
*
|
|
* If 'write' is non-zero, then we wipe out the journal on disk; otherwise
|
|
* we merely suppress recovery.
|
|
*/
|
|
|
|
int jbd2_journal_wipe(journal_t *journal, int write)
|
|
{
|
|
int err = 0;
|
|
|
|
J_ASSERT (!(journal->j_flags & JBD2_LOADED));
|
|
|
|
err = load_superblock(journal);
|
|
if (err)
|
|
return err;
|
|
|
|
if (!journal->j_tail)
|
|
goto no_recovery;
|
|
|
|
printk(KERN_WARNING "JBD2: %s recovery information on journal\n",
|
|
write ? "Clearing" : "Ignoring");
|
|
|
|
err = jbd2_journal_skip_recovery(journal);
|
|
if (write) {
|
|
/* Lock to make assertions happy... */
|
|
mutex_lock_io(&journal->j_checkpoint_mutex);
|
|
jbd2_mark_journal_empty(journal, REQ_SYNC | REQ_FUA);
|
|
mutex_unlock(&journal->j_checkpoint_mutex);
|
|
}
|
|
|
|
no_recovery:
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* void jbd2_journal_abort () - Shutdown the journal immediately.
|
|
* @journal: the journal to shutdown.
|
|
* @errno: an error number to record in the journal indicating
|
|
* the reason for the shutdown.
|
|
*
|
|
* Perform a complete, immediate shutdown of the ENTIRE
|
|
* journal (not of a single transaction). This operation cannot be
|
|
* undone without closing and reopening the journal.
|
|
*
|
|
* The jbd2_journal_abort function is intended to support higher level error
|
|
* recovery mechanisms such as the ext2/ext3 remount-readonly error
|
|
* mode.
|
|
*
|
|
* Journal abort has very specific semantics. Any existing dirty,
|
|
* unjournaled buffers in the main filesystem will still be written to
|
|
* disk by bdflush, but the journaling mechanism will be suspended
|
|
* immediately and no further transaction commits will be honoured.
|
|
*
|
|
* Any dirty, journaled buffers will be written back to disk without
|
|
* hitting the journal. Atomicity cannot be guaranteed on an aborted
|
|
* filesystem, but we _do_ attempt to leave as much data as possible
|
|
* behind for fsck to use for cleanup.
|
|
*
|
|
* Any attempt to get a new transaction handle on a journal which is in
|
|
* ABORT state will just result in an -EROFS error return. A
|
|
* jbd2_journal_stop on an existing handle will return -EIO if we have
|
|
* entered abort state during the update.
|
|
*
|
|
* Recursive transactions are not disturbed by journal abort until the
|
|
* final jbd2_journal_stop, which will receive the -EIO error.
|
|
*
|
|
* Finally, the jbd2_journal_abort call allows the caller to supply an errno
|
|
* which will be recorded (if possible) in the journal superblock. This
|
|
* allows a client to record failure conditions in the middle of a
|
|
* transaction without having to complete the transaction to record the
|
|
* failure to disk. ext3_error, for example, now uses this
|
|
* functionality.
|
|
*
|
|
*/
|
|
|
|
void jbd2_journal_abort(journal_t *journal, int errno)
|
|
{
|
|
transaction_t *transaction;
|
|
|
|
/*
|
|
* Lock the aborting procedure until everything is done, this avoid
|
|
* races between filesystem's error handling flow (e.g. ext4_abort()),
|
|
* ensure panic after the error info is written into journal's
|
|
* superblock.
|
|
*/
|
|
mutex_lock(&journal->j_abort_mutex);
|
|
/*
|
|
* ESHUTDOWN always takes precedence because a file system check
|
|
* caused by any other journal abort error is not required after
|
|
* a shutdown triggered.
|
|
*/
|
|
write_lock(&journal->j_state_lock);
|
|
if (journal->j_flags & JBD2_ABORT) {
|
|
int old_errno = journal->j_errno;
|
|
|
|
write_unlock(&journal->j_state_lock);
|
|
if (old_errno != -ESHUTDOWN && errno == -ESHUTDOWN) {
|
|
journal->j_errno = errno;
|
|
jbd2_journal_update_sb_errno(journal);
|
|
}
|
|
mutex_unlock(&journal->j_abort_mutex);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Mark the abort as occurred and start current running transaction
|
|
* to release all journaled buffer.
|
|
*/
|
|
pr_err("Aborting journal on device %s.\n", journal->j_devname);
|
|
|
|
journal->j_flags |= JBD2_ABORT;
|
|
journal->j_errno = errno;
|
|
transaction = journal->j_running_transaction;
|
|
if (transaction)
|
|
__jbd2_log_start_commit(journal, transaction->t_tid);
|
|
write_unlock(&journal->j_state_lock);
|
|
|
|
/*
|
|
* Record errno to the journal super block, so that fsck and jbd2
|
|
* layer could realise that a filesystem check is needed.
|
|
*/
|
|
jbd2_journal_update_sb_errno(journal);
|
|
mutex_unlock(&journal->j_abort_mutex);
|
|
}
|
|
|
|
/**
|
|
* int jbd2_journal_errno () - returns the journal's error state.
|
|
* @journal: journal to examine.
|
|
*
|
|
* This is the errno number set with jbd2_journal_abort(), the last
|
|
* time the journal was mounted - if the journal was stopped
|
|
* without calling abort this will be 0.
|
|
*
|
|
* If the journal has been aborted on this mount time -EROFS will
|
|
* be returned.
|
|
*/
|
|
int jbd2_journal_errno(journal_t *journal)
|
|
{
|
|
int err;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_flags & JBD2_ABORT)
|
|
err = -EROFS;
|
|
else
|
|
err = journal->j_errno;
|
|
read_unlock(&journal->j_state_lock);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* int jbd2_journal_clear_err () - clears the journal's error state
|
|
* @journal: journal to act on.
|
|
*
|
|
* An error must be cleared or acked to take a FS out of readonly
|
|
* mode.
|
|
*/
|
|
int jbd2_journal_clear_err(journal_t *journal)
|
|
{
|
|
int err = 0;
|
|
|
|
write_lock(&journal->j_state_lock);
|
|
if (journal->j_flags & JBD2_ABORT)
|
|
err = -EROFS;
|
|
else
|
|
journal->j_errno = 0;
|
|
write_unlock(&journal->j_state_lock);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* void jbd2_journal_ack_err() - Ack journal err.
|
|
* @journal: journal to act on.
|
|
*
|
|
* An error must be cleared or acked to take a FS out of readonly
|
|
* mode.
|
|
*/
|
|
void jbd2_journal_ack_err(journal_t *journal)
|
|
{
|
|
write_lock(&journal->j_state_lock);
|
|
if (journal->j_errno)
|
|
journal->j_flags |= JBD2_ACK_ERR;
|
|
write_unlock(&journal->j_state_lock);
|
|
}
|
|
|
|
int jbd2_journal_blocks_per_page(struct inode *inode)
|
|
{
|
|
return 1 << (PAGE_SHIFT - inode->i_sb->s_blocksize_bits);
|
|
}
|
|
|
|
/*
|
|
* helper functions to deal with 32 or 64bit block numbers.
|
|
*/
|
|
size_t journal_tag_bytes(journal_t *journal)
|
|
{
|
|
size_t sz;
|
|
|
|
if (jbd2_has_feature_csum3(journal))
|
|
return sizeof(journal_block_tag3_t);
|
|
|
|
sz = sizeof(journal_block_tag_t);
|
|
|
|
if (jbd2_has_feature_csum2(journal))
|
|
sz += sizeof(__u16);
|
|
|
|
if (jbd2_has_feature_64bit(journal))
|
|
return sz;
|
|
else
|
|
return sz - sizeof(__u32);
|
|
}
|
|
|
|
/*
|
|
* JBD memory management
|
|
*
|
|
* These functions are used to allocate block-sized chunks of memory
|
|
* used for making copies of buffer_head data. Very often it will be
|
|
* page-sized chunks of data, but sometimes it will be in
|
|
* sub-page-size chunks. (For example, 16k pages on Power systems
|
|
* with a 4k block file system.) For blocks smaller than a page, we
|
|
* use a SLAB allocator. There are slab caches for each block size,
|
|
* which are allocated at mount time, if necessary, and we only free
|
|
* (all of) the slab caches when/if the jbd2 module is unloaded. For
|
|
* this reason we don't need to a mutex to protect access to
|
|
* jbd2_slab[] allocating or releasing memory; only in
|
|
* jbd2_journal_create_slab().
|
|
*/
|
|
#define JBD2_MAX_SLABS 8
|
|
static struct kmem_cache *jbd2_slab[JBD2_MAX_SLABS];
|
|
|
|
static const char *jbd2_slab_names[JBD2_MAX_SLABS] = {
|
|
"jbd2_1k", "jbd2_2k", "jbd2_4k", "jbd2_8k",
|
|
"jbd2_16k", "jbd2_32k", "jbd2_64k", "jbd2_128k"
|
|
};
|
|
|
|
|
|
static void jbd2_journal_destroy_slabs(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < JBD2_MAX_SLABS; i++) {
|
|
kmem_cache_destroy(jbd2_slab[i]);
|
|
jbd2_slab[i] = NULL;
|
|
}
|
|
}
|
|
|
|
static int jbd2_journal_create_slab(size_t size)
|
|
{
|
|
static DEFINE_MUTEX(jbd2_slab_create_mutex);
|
|
int i = order_base_2(size) - 10;
|
|
size_t slab_size;
|
|
|
|
if (size == PAGE_SIZE)
|
|
return 0;
|
|
|
|
if (i >= JBD2_MAX_SLABS)
|
|
return -EINVAL;
|
|
|
|
if (unlikely(i < 0))
|
|
i = 0;
|
|
mutex_lock(&jbd2_slab_create_mutex);
|
|
if (jbd2_slab[i]) {
|
|
mutex_unlock(&jbd2_slab_create_mutex);
|
|
return 0; /* Already created */
|
|
}
|
|
|
|
slab_size = 1 << (i+10);
|
|
jbd2_slab[i] = kmem_cache_create(jbd2_slab_names[i], slab_size,
|
|
slab_size, 0, NULL);
|
|
mutex_unlock(&jbd2_slab_create_mutex);
|
|
if (!jbd2_slab[i]) {
|
|
printk(KERN_EMERG "JBD2: no memory for jbd2_slab cache\n");
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct kmem_cache *get_slab(size_t size)
|
|
{
|
|
int i = order_base_2(size) - 10;
|
|
|
|
BUG_ON(i >= JBD2_MAX_SLABS);
|
|
if (unlikely(i < 0))
|
|
i = 0;
|
|
BUG_ON(jbd2_slab[i] == NULL);
|
|
return jbd2_slab[i];
|
|
}
|
|
|
|
void *jbd2_alloc(size_t size, gfp_t flags)
|
|
{
|
|
void *ptr;
|
|
|
|
BUG_ON(size & (size-1)); /* Must be a power of 2 */
|
|
|
|
if (size < PAGE_SIZE)
|
|
ptr = kmem_cache_alloc(get_slab(size), flags);
|
|
else
|
|
ptr = (void *)__get_free_pages(flags, get_order(size));
|
|
|
|
/* Check alignment; SLUB has gotten this wrong in the past,
|
|
* and this can lead to user data corruption! */
|
|
BUG_ON(((unsigned long) ptr) & (size-1));
|
|
|
|
return ptr;
|
|
}
|
|
|
|
void jbd2_free(void *ptr, size_t size)
|
|
{
|
|
if (size < PAGE_SIZE)
|
|
kmem_cache_free(get_slab(size), ptr);
|
|
else
|
|
free_pages((unsigned long)ptr, get_order(size));
|
|
};
|
|
|
|
/*
|
|
* Journal_head storage management
|
|
*/
|
|
static struct kmem_cache *jbd2_journal_head_cache;
|
|
#ifdef CONFIG_JBD2_DEBUG
|
|
static atomic_t nr_journal_heads = ATOMIC_INIT(0);
|
|
#endif
|
|
|
|
static int __init jbd2_journal_init_journal_head_cache(void)
|
|
{
|
|
J_ASSERT(!jbd2_journal_head_cache);
|
|
jbd2_journal_head_cache = kmem_cache_create("jbd2_journal_head",
|
|
sizeof(struct journal_head),
|
|
0, /* offset */
|
|
SLAB_TEMPORARY | SLAB_TYPESAFE_BY_RCU,
|
|
NULL); /* ctor */
|
|
if (!jbd2_journal_head_cache) {
|
|
printk(KERN_EMERG "JBD2: no memory for journal_head cache\n");
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void jbd2_journal_destroy_journal_head_cache(void)
|
|
{
|
|
kmem_cache_destroy(jbd2_journal_head_cache);
|
|
jbd2_journal_head_cache = NULL;
|
|
}
|
|
|
|
/*
|
|
* journal_head splicing and dicing
|
|
*/
|
|
static struct journal_head *journal_alloc_journal_head(void)
|
|
{
|
|
struct journal_head *ret;
|
|
|
|
#ifdef CONFIG_JBD2_DEBUG
|
|
atomic_inc(&nr_journal_heads);
|
|
#endif
|
|
ret = kmem_cache_zalloc(jbd2_journal_head_cache, GFP_NOFS);
|
|
if (!ret) {
|
|
jbd_debug(1, "out of memory for journal_head\n");
|
|
pr_notice_ratelimited("ENOMEM in %s, retrying.\n", __func__);
|
|
ret = kmem_cache_zalloc(jbd2_journal_head_cache,
|
|
GFP_NOFS | __GFP_NOFAIL);
|
|
}
|
|
if (ret)
|
|
spin_lock_init(&ret->b_state_lock);
|
|
return ret;
|
|
}
|
|
|
|
static void journal_free_journal_head(struct journal_head *jh)
|
|
{
|
|
#ifdef CONFIG_JBD2_DEBUG
|
|
atomic_dec(&nr_journal_heads);
|
|
memset(jh, JBD2_POISON_FREE, sizeof(*jh));
|
|
#endif
|
|
kmem_cache_free(jbd2_journal_head_cache, jh);
|
|
}
|
|
|
|
/*
|
|
* A journal_head is attached to a buffer_head whenever JBD has an
|
|
* interest in the buffer.
|
|
*
|
|
* Whenever a buffer has an attached journal_head, its ->b_state:BH_JBD bit
|
|
* is set. This bit is tested in core kernel code where we need to take
|
|
* JBD-specific actions. Testing the zeroness of ->b_private is not reliable
|
|
* there.
|
|
*
|
|
* When a buffer has its BH_JBD bit set, its ->b_count is elevated by one.
|
|
*
|
|
* When a buffer has its BH_JBD bit set it is immune from being released by
|
|
* core kernel code, mainly via ->b_count.
|
|
*
|
|
* A journal_head is detached from its buffer_head when the journal_head's
|
|
* b_jcount reaches zero. Running transaction (b_transaction) and checkpoint
|
|
* transaction (b_cp_transaction) hold their references to b_jcount.
|
|
*
|
|
* Various places in the kernel want to attach a journal_head to a buffer_head
|
|
* _before_ attaching the journal_head to a transaction. To protect the
|
|
* journal_head in this situation, jbd2_journal_add_journal_head elevates the
|
|
* journal_head's b_jcount refcount by one. The caller must call
|
|
* jbd2_journal_put_journal_head() to undo this.
|
|
*
|
|
* So the typical usage would be:
|
|
*
|
|
* (Attach a journal_head if needed. Increments b_jcount)
|
|
* struct journal_head *jh = jbd2_journal_add_journal_head(bh);
|
|
* ...
|
|
* (Get another reference for transaction)
|
|
* jbd2_journal_grab_journal_head(bh);
|
|
* jh->b_transaction = xxx;
|
|
* (Put original reference)
|
|
* jbd2_journal_put_journal_head(jh);
|
|
*/
|
|
|
|
/*
|
|
* Give a buffer_head a journal_head.
|
|
*
|
|
* May sleep.
|
|
*/
|
|
struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh)
|
|
{
|
|
struct journal_head *jh;
|
|
struct journal_head *new_jh = NULL;
|
|
|
|
repeat:
|
|
if (!buffer_jbd(bh))
|
|
new_jh = journal_alloc_journal_head();
|
|
|
|
jbd_lock_bh_journal_head(bh);
|
|
if (buffer_jbd(bh)) {
|
|
jh = bh2jh(bh);
|
|
} else {
|
|
J_ASSERT_BH(bh,
|
|
(atomic_read(&bh->b_count) > 0) ||
|
|
(bh->b_page && bh->b_page->mapping));
|
|
|
|
if (!new_jh) {
|
|
jbd_unlock_bh_journal_head(bh);
|
|
goto repeat;
|
|
}
|
|
|
|
jh = new_jh;
|
|
new_jh = NULL; /* We consumed it */
|
|
set_buffer_jbd(bh);
|
|
bh->b_private = jh;
|
|
jh->b_bh = bh;
|
|
get_bh(bh);
|
|
BUFFER_TRACE(bh, "added journal_head");
|
|
}
|
|
jh->b_jcount++;
|
|
jbd_unlock_bh_journal_head(bh);
|
|
if (new_jh)
|
|
journal_free_journal_head(new_jh);
|
|
return bh->b_private;
|
|
}
|
|
|
|
/*
|
|
* Grab a ref against this buffer_head's journal_head. If it ended up not
|
|
* having a journal_head, return NULL
|
|
*/
|
|
struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh)
|
|
{
|
|
struct journal_head *jh = NULL;
|
|
|
|
jbd_lock_bh_journal_head(bh);
|
|
if (buffer_jbd(bh)) {
|
|
jh = bh2jh(bh);
|
|
jh->b_jcount++;
|
|
}
|
|
jbd_unlock_bh_journal_head(bh);
|
|
return jh;
|
|
}
|
|
|
|
static void __journal_remove_journal_head(struct buffer_head *bh)
|
|
{
|
|
struct journal_head *jh = bh2jh(bh);
|
|
|
|
J_ASSERT_JH(jh, jh->b_transaction == NULL);
|
|
J_ASSERT_JH(jh, jh->b_next_transaction == NULL);
|
|
J_ASSERT_JH(jh, jh->b_cp_transaction == NULL);
|
|
J_ASSERT_JH(jh, jh->b_jlist == BJ_None);
|
|
J_ASSERT_BH(bh, buffer_jbd(bh));
|
|
J_ASSERT_BH(bh, jh2bh(jh) == bh);
|
|
BUFFER_TRACE(bh, "remove journal_head");
|
|
|
|
/* Unlink before dropping the lock */
|
|
bh->b_private = NULL;
|
|
jh->b_bh = NULL; /* debug, really */
|
|
clear_buffer_jbd(bh);
|
|
}
|
|
|
|
static void journal_release_journal_head(struct journal_head *jh, size_t b_size)
|
|
{
|
|
if (jh->b_frozen_data) {
|
|
printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__);
|
|
jbd2_free(jh->b_frozen_data, b_size);
|
|
}
|
|
if (jh->b_committed_data) {
|
|
printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__);
|
|
jbd2_free(jh->b_committed_data, b_size);
|
|
}
|
|
journal_free_journal_head(jh);
|
|
}
|
|
|
|
/*
|
|
* Drop a reference on the passed journal_head. If it fell to zero then
|
|
* release the journal_head from the buffer_head.
|
|
*/
|
|
void jbd2_journal_put_journal_head(struct journal_head *jh)
|
|
{
|
|
struct buffer_head *bh = jh2bh(jh);
|
|
|
|
jbd_lock_bh_journal_head(bh);
|
|
J_ASSERT_JH(jh, jh->b_jcount > 0);
|
|
--jh->b_jcount;
|
|
if (!jh->b_jcount) {
|
|
__journal_remove_journal_head(bh);
|
|
jbd_unlock_bh_journal_head(bh);
|
|
journal_release_journal_head(jh, bh->b_size);
|
|
__brelse(bh);
|
|
} else {
|
|
jbd_unlock_bh_journal_head(bh);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize jbd inode head
|
|
*/
|
|
void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode)
|
|
{
|
|
jinode->i_transaction = NULL;
|
|
jinode->i_next_transaction = NULL;
|
|
jinode->i_vfs_inode = inode;
|
|
jinode->i_flags = 0;
|
|
jinode->i_dirty_start = 0;
|
|
jinode->i_dirty_end = 0;
|
|
INIT_LIST_HEAD(&jinode->i_list);
|
|
}
|
|
|
|
/*
|
|
* Function to be called before we start removing inode from memory (i.e.,
|
|
* clear_inode() is a fine place to be called from). It removes inode from
|
|
* transaction's lists.
|
|
*/
|
|
void jbd2_journal_release_jbd_inode(journal_t *journal,
|
|
struct jbd2_inode *jinode)
|
|
{
|
|
if (!journal)
|
|
return;
|
|
restart:
|
|
spin_lock(&journal->j_list_lock);
|
|
/* Is commit writing out inode - we have to wait */
|
|
if (jinode->i_flags & JI_COMMIT_RUNNING) {
|
|
wait_queue_head_t *wq;
|
|
DEFINE_WAIT_BIT(wait, &jinode->i_flags, __JI_COMMIT_RUNNING);
|
|
wq = bit_waitqueue(&jinode->i_flags, __JI_COMMIT_RUNNING);
|
|
prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
|
|
spin_unlock(&journal->j_list_lock);
|
|
schedule();
|
|
finish_wait(wq, &wait.wq_entry);
|
|
goto restart;
|
|
}
|
|
|
|
if (jinode->i_transaction) {
|
|
list_del(&jinode->i_list);
|
|
jinode->i_transaction = NULL;
|
|
}
|
|
spin_unlock(&journal->j_list_lock);
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
#define JBD2_STATS_PROC_NAME "fs/jbd2"
|
|
|
|
static void __init jbd2_create_jbd_stats_proc_entry(void)
|
|
{
|
|
proc_jbd2_stats = proc_mkdir(JBD2_STATS_PROC_NAME, NULL);
|
|
}
|
|
|
|
static void __exit jbd2_remove_jbd_stats_proc_entry(void)
|
|
{
|
|
if (proc_jbd2_stats)
|
|
remove_proc_entry(JBD2_STATS_PROC_NAME, NULL);
|
|
}
|
|
|
|
#else
|
|
|
|
#define jbd2_create_jbd_stats_proc_entry() do {} while (0)
|
|
#define jbd2_remove_jbd_stats_proc_entry() do {} while (0)
|
|
|
|
#endif
|
|
|
|
struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache;
|
|
|
|
static int __init jbd2_journal_init_inode_cache(void)
|
|
{
|
|
J_ASSERT(!jbd2_inode_cache);
|
|
jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0);
|
|
if (!jbd2_inode_cache) {
|
|
pr_emerg("JBD2: failed to create inode cache\n");
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int __init jbd2_journal_init_handle_cache(void)
|
|
{
|
|
J_ASSERT(!jbd2_handle_cache);
|
|
jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY);
|
|
if (!jbd2_handle_cache) {
|
|
printk(KERN_EMERG "JBD2: failed to create handle cache\n");
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void jbd2_journal_destroy_inode_cache(void)
|
|
{
|
|
kmem_cache_destroy(jbd2_inode_cache);
|
|
jbd2_inode_cache = NULL;
|
|
}
|
|
|
|
static void jbd2_journal_destroy_handle_cache(void)
|
|
{
|
|
kmem_cache_destroy(jbd2_handle_cache);
|
|
jbd2_handle_cache = NULL;
|
|
}
|
|
|
|
/*
|
|
* Module startup and shutdown
|
|
*/
|
|
|
|
static int __init journal_init_caches(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = jbd2_journal_init_revoke_record_cache();
|
|
if (ret == 0)
|
|
ret = jbd2_journal_init_revoke_table_cache();
|
|
if (ret == 0)
|
|
ret = jbd2_journal_init_journal_head_cache();
|
|
if (ret == 0)
|
|
ret = jbd2_journal_init_handle_cache();
|
|
if (ret == 0)
|
|
ret = jbd2_journal_init_inode_cache();
|
|
if (ret == 0)
|
|
ret = jbd2_journal_init_transaction_cache();
|
|
return ret;
|
|
}
|
|
|
|
static void jbd2_journal_destroy_caches(void)
|
|
{
|
|
jbd2_journal_destroy_revoke_record_cache();
|
|
jbd2_journal_destroy_revoke_table_cache();
|
|
jbd2_journal_destroy_journal_head_cache();
|
|
jbd2_journal_destroy_handle_cache();
|
|
jbd2_journal_destroy_inode_cache();
|
|
jbd2_journal_destroy_transaction_cache();
|
|
jbd2_journal_destroy_slabs();
|
|
}
|
|
|
|
static int __init journal_init(void)
|
|
{
|
|
int ret;
|
|
|
|
BUILD_BUG_ON(sizeof(struct journal_superblock_s) != 1024);
|
|
|
|
ret = journal_init_caches();
|
|
if (ret == 0) {
|
|
jbd2_create_jbd_stats_proc_entry();
|
|
} else {
|
|
jbd2_journal_destroy_caches();
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void __exit journal_exit(void)
|
|
{
|
|
#ifdef CONFIG_JBD2_DEBUG
|
|
int n = atomic_read(&nr_journal_heads);
|
|
if (n)
|
|
printk(KERN_ERR "JBD2: leaked %d journal_heads!\n", n);
|
|
#endif
|
|
jbd2_remove_jbd_stats_proc_entry();
|
|
jbd2_journal_destroy_caches();
|
|
}
|
|
|
|
MODULE_LICENSE("GPL");
|
|
module_init(journal_init);
|
|
module_exit(journal_exit);
|
|
|