![Andrew Morton](/assets/img/avatar_default.png)
Someone's tab key is emitting spaces. Attempt to repair some of the damage. Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2153 lines
56 KiB
C
2153 lines
56 KiB
C
/*
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* Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
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* Written by Alex Tomas <alex@clusterfs.com>
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*
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* Architecture independence:
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* Copyright (c) 2005, Bull S.A.
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* Written by Pierre Peiffer <pierre.peiffer@bull.net>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public Licens
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
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*/
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/*
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* Extents support for EXT4
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*
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* TODO:
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* - ext4*_error() should be used in some situations
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* - analyze all BUG()/BUG_ON(), use -EIO where appropriate
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* - smart tree reduction
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/time.h>
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#include <linux/ext4_jbd2.h>
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#include <linux/jbd.h>
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#include <linux/smp_lock.h>
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#include <linux/highuid.h>
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#include <linux/pagemap.h>
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#include <linux/quotaops.h>
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#include <linux/string.h>
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#include <linux/slab.h>
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#include <linux/ext4_fs_extents.h>
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#include <asm/uaccess.h>
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/*
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* ext_pblock:
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* combine low and high parts of physical block number into ext4_fsblk_t
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*/
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static inline ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
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{
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ext4_fsblk_t block;
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block = le32_to_cpu(ex->ee_start);
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block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1;
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return block;
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}
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/*
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* idx_pblock:
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* combine low and high parts of a leaf physical block number into ext4_fsblk_t
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*/
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static inline ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
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{
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ext4_fsblk_t block;
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block = le32_to_cpu(ix->ei_leaf);
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block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1;
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return block;
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}
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/*
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* ext4_ext_store_pblock:
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* stores a large physical block number into an extent struct,
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* breaking it into parts
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*/
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static inline void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
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{
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ex->ee_start = cpu_to_le32((unsigned long) (pb & 0xffffffff));
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ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
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}
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/*
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* ext4_idx_store_pblock:
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* stores a large physical block number into an index struct,
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* breaking it into parts
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*/
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static inline void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
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{
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ix->ei_leaf = cpu_to_le32((unsigned long) (pb & 0xffffffff));
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ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
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}
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static int ext4_ext_check_header(const char *function, struct inode *inode,
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struct ext4_extent_header *eh)
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{
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const char *error_msg = NULL;
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if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
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error_msg = "invalid magic";
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goto corrupted;
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}
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if (unlikely(eh->eh_max == 0)) {
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error_msg = "invalid eh_max";
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goto corrupted;
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}
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if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
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error_msg = "invalid eh_entries";
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goto corrupted;
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}
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return 0;
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corrupted:
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ext4_error(inode->i_sb, function,
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"bad header in inode #%lu: %s - magic %x, "
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"entries %u, max %u, depth %u",
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inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic),
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le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
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le16_to_cpu(eh->eh_depth));
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return -EIO;
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}
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static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed)
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{
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int err;
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if (handle->h_buffer_credits > needed)
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return handle;
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if (!ext4_journal_extend(handle, needed))
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return handle;
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err = ext4_journal_restart(handle, needed);
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return handle;
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}
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/*
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* could return:
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* - EROFS
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* - ENOMEM
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*/
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static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
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struct ext4_ext_path *path)
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{
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if (path->p_bh) {
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/* path points to block */
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return ext4_journal_get_write_access(handle, path->p_bh);
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}
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/* path points to leaf/index in inode body */
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/* we use in-core data, no need to protect them */
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return 0;
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}
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/*
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* could return:
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* - EROFS
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* - ENOMEM
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* - EIO
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*/
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static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
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struct ext4_ext_path *path)
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{
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int err;
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if (path->p_bh) {
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/* path points to block */
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err = ext4_journal_dirty_metadata(handle, path->p_bh);
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} else {
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/* path points to leaf/index in inode body */
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err = ext4_mark_inode_dirty(handle, inode);
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}
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return err;
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}
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static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
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struct ext4_ext_path *path,
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ext4_fsblk_t block)
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{
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struct ext4_inode_info *ei = EXT4_I(inode);
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ext4_fsblk_t bg_start;
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ext4_grpblk_t colour;
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int depth;
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if (path) {
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struct ext4_extent *ex;
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depth = path->p_depth;
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/* try to predict block placement */
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if ((ex = path[depth].p_ext))
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return ext_pblock(ex)+(block-le32_to_cpu(ex->ee_block));
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/* it looks like index is empty;
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* try to find starting block from index itself */
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if (path[depth].p_bh)
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return path[depth].p_bh->b_blocknr;
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}
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/* OK. use inode's group */
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bg_start = (ei->i_block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) +
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le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block);
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colour = (current->pid % 16) *
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(EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
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return bg_start + colour + block;
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}
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static ext4_fsblk_t
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ext4_ext_new_block(handle_t *handle, struct inode *inode,
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struct ext4_ext_path *path,
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struct ext4_extent *ex, int *err)
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{
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ext4_fsblk_t goal, newblock;
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goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
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newblock = ext4_new_block(handle, inode, goal, err);
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return newblock;
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}
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static inline int ext4_ext_space_block(struct inode *inode)
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{
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int size;
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size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
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/ sizeof(struct ext4_extent);
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#ifdef AGRESSIVE_TEST
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if (size > 6)
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size = 6;
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#endif
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return size;
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}
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static inline int ext4_ext_space_block_idx(struct inode *inode)
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{
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int size;
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size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
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/ sizeof(struct ext4_extent_idx);
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#ifdef AGRESSIVE_TEST
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if (size > 5)
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size = 5;
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#endif
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return size;
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}
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static inline int ext4_ext_space_root(struct inode *inode)
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{
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int size;
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size = sizeof(EXT4_I(inode)->i_data);
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size -= sizeof(struct ext4_extent_header);
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size /= sizeof(struct ext4_extent);
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#ifdef AGRESSIVE_TEST
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if (size > 3)
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size = 3;
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#endif
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return size;
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}
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static inline int ext4_ext_space_root_idx(struct inode *inode)
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{
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int size;
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size = sizeof(EXT4_I(inode)->i_data);
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size -= sizeof(struct ext4_extent_header);
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size /= sizeof(struct ext4_extent_idx);
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#ifdef AGRESSIVE_TEST
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if (size > 4)
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size = 4;
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#endif
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return size;
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}
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#ifdef EXT_DEBUG
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static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
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{
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int k, l = path->p_depth;
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ext_debug("path:");
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for (k = 0; k <= l; k++, path++) {
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if (path->p_idx) {
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ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
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idx_pblock(path->p_idx));
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} else if (path->p_ext) {
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ext_debug(" %d:%d:%llu ",
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le32_to_cpu(path->p_ext->ee_block),
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le16_to_cpu(path->p_ext->ee_len),
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ext_pblock(path->p_ext));
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} else
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ext_debug(" []");
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}
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ext_debug("\n");
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}
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static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
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{
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int depth = ext_depth(inode);
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struct ext4_extent_header *eh;
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struct ext4_extent *ex;
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int i;
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if (!path)
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return;
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eh = path[depth].p_hdr;
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ex = EXT_FIRST_EXTENT(eh);
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for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
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ext_debug("%d:%d:%llu ", le32_to_cpu(ex->ee_block),
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le16_to_cpu(ex->ee_len), ext_pblock(ex));
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}
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ext_debug("\n");
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}
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#else
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#define ext4_ext_show_path(inode,path)
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#define ext4_ext_show_leaf(inode,path)
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#endif
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static void ext4_ext_drop_refs(struct ext4_ext_path *path)
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{
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int depth = path->p_depth;
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int i;
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for (i = 0; i <= depth; i++, path++)
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if (path->p_bh) {
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brelse(path->p_bh);
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path->p_bh = NULL;
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}
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}
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/*
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* ext4_ext_binsearch_idx:
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* binary search for the closest index of the given block
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*/
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static void
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ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block)
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{
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struct ext4_extent_header *eh = path->p_hdr;
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struct ext4_extent_idx *r, *l, *m;
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BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
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BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
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BUG_ON(le16_to_cpu(eh->eh_entries) <= 0);
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ext_debug("binsearch for %d(idx): ", block);
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l = EXT_FIRST_INDEX(eh) + 1;
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r = EXT_FIRST_INDEX(eh) + le16_to_cpu(eh->eh_entries) - 1;
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while (l <= r) {
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m = l + (r - l) / 2;
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if (block < le32_to_cpu(m->ei_block))
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r = m - 1;
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else
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l = m + 1;
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ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ei_block,
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m, m->ei_block, r, r->ei_block);
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}
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path->p_idx = l - 1;
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ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
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idx_block(path->p_idx));
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#ifdef CHECK_BINSEARCH
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{
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struct ext4_extent_idx *chix, *ix;
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int k;
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chix = ix = EXT_FIRST_INDEX(eh);
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for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
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if (k != 0 &&
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le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
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printk("k=%d, ix=0x%p, first=0x%p\n", k,
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ix, EXT_FIRST_INDEX(eh));
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printk("%u <= %u\n",
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le32_to_cpu(ix->ei_block),
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le32_to_cpu(ix[-1].ei_block));
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}
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BUG_ON(k && le32_to_cpu(ix->ei_block)
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<= le32_to_cpu(ix[-1].ei_block));
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if (block < le32_to_cpu(ix->ei_block))
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break;
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chix = ix;
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}
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BUG_ON(chix != path->p_idx);
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}
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#endif
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}
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/*
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* ext4_ext_binsearch:
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* binary search for closest extent of the given block
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*/
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static void
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ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
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{
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struct ext4_extent_header *eh = path->p_hdr;
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struct ext4_extent *r, *l, *m;
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BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
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BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
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if (eh->eh_entries == 0) {
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/*
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* this leaf is empty:
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* we get such a leaf in split/add case
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*/
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return;
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}
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ext_debug("binsearch for %d: ", block);
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l = EXT_FIRST_EXTENT(eh) + 1;
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r = EXT_FIRST_EXTENT(eh) + le16_to_cpu(eh->eh_entries) - 1;
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while (l <= r) {
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m = l + (r - l) / 2;
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if (block < le32_to_cpu(m->ee_block))
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r = m - 1;
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else
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l = m + 1;
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ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ee_block,
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m, m->ee_block, r, r->ee_block);
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}
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path->p_ext = l - 1;
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ext_debug(" -> %d:%llu:%d ",
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le32_to_cpu(path->p_ext->ee_block),
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ext_pblock(path->p_ext),
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le16_to_cpu(path->p_ext->ee_len));
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#ifdef CHECK_BINSEARCH
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{
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struct ext4_extent *chex, *ex;
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int k;
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chex = ex = EXT_FIRST_EXTENT(eh);
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for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
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BUG_ON(k && le32_to_cpu(ex->ee_block)
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<= le32_to_cpu(ex[-1].ee_block));
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if (block < le32_to_cpu(ex->ee_block))
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break;
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chex = ex;
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}
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BUG_ON(chex != path->p_ext);
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}
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#endif
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|
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}
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int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
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{
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struct ext4_extent_header *eh;
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eh = ext_inode_hdr(inode);
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eh->eh_depth = 0;
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eh->eh_entries = 0;
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eh->eh_magic = EXT4_EXT_MAGIC;
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eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode));
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ext4_mark_inode_dirty(handle, inode);
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ext4_ext_invalidate_cache(inode);
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return 0;
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}
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|
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struct ext4_ext_path *
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ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
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{
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struct ext4_extent_header *eh;
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struct buffer_head *bh;
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short int depth, i, ppos = 0, alloc = 0;
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|
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eh = ext_inode_hdr(inode);
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BUG_ON(eh == NULL);
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if (ext4_ext_check_header(__FUNCTION__, inode, eh))
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return ERR_PTR(-EIO);
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i = depth = ext_depth(inode);
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|
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/* account possible depth increase */
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if (!path) {
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path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 2),
|
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GFP_NOFS);
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if (!path)
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return ERR_PTR(-ENOMEM);
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alloc = 1;
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}
|
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memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1));
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path[0].p_hdr = eh;
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|
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/* walk through the tree */
|
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while (i) {
|
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ext_debug("depth %d: num %d, max %d\n",
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ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
|
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ext4_ext_binsearch_idx(inode, path + ppos, block);
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path[ppos].p_block = idx_pblock(path[ppos].p_idx);
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path[ppos].p_depth = i;
|
|
path[ppos].p_ext = NULL;
|
|
|
|
bh = sb_bread(inode->i_sb, path[ppos].p_block);
|
|
if (!bh)
|
|
goto err;
|
|
|
|
eh = ext_block_hdr(bh);
|
|
ppos++;
|
|
BUG_ON(ppos > depth);
|
|
path[ppos].p_bh = bh;
|
|
path[ppos].p_hdr = eh;
|
|
i--;
|
|
|
|
if (ext4_ext_check_header(__FUNCTION__, inode, eh))
|
|
goto err;
|
|
}
|
|
|
|
path[ppos].p_depth = i;
|
|
path[ppos].p_hdr = eh;
|
|
path[ppos].p_ext = NULL;
|
|
path[ppos].p_idx = NULL;
|
|
|
|
if (ext4_ext_check_header(__FUNCTION__, inode, eh))
|
|
goto err;
|
|
|
|
/* find extent */
|
|
ext4_ext_binsearch(inode, path + ppos, block);
|
|
|
|
ext4_ext_show_path(inode, path);
|
|
|
|
return path;
|
|
|
|
err:
|
|
ext4_ext_drop_refs(path);
|
|
if (alloc)
|
|
kfree(path);
|
|
return ERR_PTR(-EIO);
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_insert_index:
|
|
* insert new index [@logical;@ptr] into the block at @curp;
|
|
* check where to insert: before @curp or after @curp
|
|
*/
|
|
static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *curp,
|
|
int logical, ext4_fsblk_t ptr)
|
|
{
|
|
struct ext4_extent_idx *ix;
|
|
int len, err;
|
|
|
|
if ((err = ext4_ext_get_access(handle, inode, curp)))
|
|
return err;
|
|
|
|
BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block));
|
|
len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
|
|
if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
|
|
/* insert after */
|
|
if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
|
|
len = (len - 1) * sizeof(struct ext4_extent_idx);
|
|
len = len < 0 ? 0 : len;
|
|
ext_debug("insert new index %d after: %d. "
|
|
"move %d from 0x%p to 0x%p\n",
|
|
logical, ptr, len,
|
|
(curp->p_idx + 1), (curp->p_idx + 2));
|
|
memmove(curp->p_idx + 2, curp->p_idx + 1, len);
|
|
}
|
|
ix = curp->p_idx + 1;
|
|
} else {
|
|
/* insert before */
|
|
len = len * sizeof(struct ext4_extent_idx);
|
|
len = len < 0 ? 0 : len;
|
|
ext_debug("insert new index %d before: %d. "
|
|
"move %d from 0x%p to 0x%p\n",
|
|
logical, ptr, len,
|
|
curp->p_idx, (curp->p_idx + 1));
|
|
memmove(curp->p_idx + 1, curp->p_idx, len);
|
|
ix = curp->p_idx;
|
|
}
|
|
|
|
ix->ei_block = cpu_to_le32(logical);
|
|
ext4_idx_store_pblock(ix, ptr);
|
|
curp->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(curp->p_hdr->eh_entries)+1);
|
|
|
|
BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries)
|
|
> le16_to_cpu(curp->p_hdr->eh_max));
|
|
BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr));
|
|
|
|
err = ext4_ext_dirty(handle, inode, curp);
|
|
ext4_std_error(inode->i_sb, err);
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_split:
|
|
* inserts new subtree into the path, using free index entry
|
|
* at depth @at:
|
|
* - allocates all needed blocks (new leaf and all intermediate index blocks)
|
|
* - makes decision where to split
|
|
* - moves remaining extents and index entries (right to the split point)
|
|
* into the newly allocated blocks
|
|
* - initializes subtree
|
|
*/
|
|
static int ext4_ext_split(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path,
|
|
struct ext4_extent *newext, int at)
|
|
{
|
|
struct buffer_head *bh = NULL;
|
|
int depth = ext_depth(inode);
|
|
struct ext4_extent_header *neh;
|
|
struct ext4_extent_idx *fidx;
|
|
struct ext4_extent *ex;
|
|
int i = at, k, m, a;
|
|
ext4_fsblk_t newblock, oldblock;
|
|
__le32 border;
|
|
ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
|
|
int err = 0;
|
|
|
|
/* make decision: where to split? */
|
|
/* FIXME: now decision is simplest: at current extent */
|
|
|
|
/* if current leaf will be split, then we should use
|
|
* border from split point */
|
|
BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr));
|
|
if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
|
|
border = path[depth].p_ext[1].ee_block;
|
|
ext_debug("leaf will be split."
|
|
" next leaf starts at %d\n",
|
|
le32_to_cpu(border));
|
|
} else {
|
|
border = newext->ee_block;
|
|
ext_debug("leaf will be added."
|
|
" next leaf starts at %d\n",
|
|
le32_to_cpu(border));
|
|
}
|
|
|
|
/*
|
|
* If error occurs, then we break processing
|
|
* and mark filesystem read-only. index won't
|
|
* be inserted and tree will be in consistent
|
|
* state. Next mount will repair buffers too.
|
|
*/
|
|
|
|
/*
|
|
* Get array to track all allocated blocks.
|
|
* We need this to handle errors and free blocks
|
|
* upon them.
|
|
*/
|
|
ablocks = kmalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
|
|
if (!ablocks)
|
|
return -ENOMEM;
|
|
memset(ablocks, 0, sizeof(ext4_fsblk_t) * depth);
|
|
|
|
/* allocate all needed blocks */
|
|
ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
|
|
for (a = 0; a < depth - at; a++) {
|
|
newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
|
|
if (newblock == 0)
|
|
goto cleanup;
|
|
ablocks[a] = newblock;
|
|
}
|
|
|
|
/* initialize new leaf */
|
|
newblock = ablocks[--a];
|
|
BUG_ON(newblock == 0);
|
|
bh = sb_getblk(inode->i_sb, newblock);
|
|
if (!bh) {
|
|
err = -EIO;
|
|
goto cleanup;
|
|
}
|
|
lock_buffer(bh);
|
|
|
|
if ((err = ext4_journal_get_create_access(handle, bh)))
|
|
goto cleanup;
|
|
|
|
neh = ext_block_hdr(bh);
|
|
neh->eh_entries = 0;
|
|
neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode));
|
|
neh->eh_magic = EXT4_EXT_MAGIC;
|
|
neh->eh_depth = 0;
|
|
ex = EXT_FIRST_EXTENT(neh);
|
|
|
|
/* move remainder of path[depth] to the new leaf */
|
|
BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max);
|
|
/* start copy from next extent */
|
|
/* TODO: we could do it by single memmove */
|
|
m = 0;
|
|
path[depth].p_ext++;
|
|
while (path[depth].p_ext <=
|
|
EXT_MAX_EXTENT(path[depth].p_hdr)) {
|
|
ext_debug("move %d:%llu:%d in new leaf %llu\n",
|
|
le32_to_cpu(path[depth].p_ext->ee_block),
|
|
ext_pblock(path[depth].p_ext),
|
|
le16_to_cpu(path[depth].p_ext->ee_len),
|
|
newblock);
|
|
/*memmove(ex++, path[depth].p_ext++,
|
|
sizeof(struct ext4_extent));
|
|
neh->eh_entries++;*/
|
|
path[depth].p_ext++;
|
|
m++;
|
|
}
|
|
if (m) {
|
|
memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
|
|
neh->eh_entries = cpu_to_le16(le16_to_cpu(neh->eh_entries)+m);
|
|
}
|
|
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
|
|
if ((err = ext4_journal_dirty_metadata(handle, bh)))
|
|
goto cleanup;
|
|
brelse(bh);
|
|
bh = NULL;
|
|
|
|
/* correct old leaf */
|
|
if (m) {
|
|
if ((err = ext4_ext_get_access(handle, inode, path + depth)))
|
|
goto cleanup;
|
|
path[depth].p_hdr->eh_entries =
|
|
cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m);
|
|
if ((err = ext4_ext_dirty(handle, inode, path + depth)))
|
|
goto cleanup;
|
|
|
|
}
|
|
|
|
/* create intermediate indexes */
|
|
k = depth - at - 1;
|
|
BUG_ON(k < 0);
|
|
if (k)
|
|
ext_debug("create %d intermediate indices\n", k);
|
|
/* insert new index into current index block */
|
|
/* current depth stored in i var */
|
|
i = depth - 1;
|
|
while (k--) {
|
|
oldblock = newblock;
|
|
newblock = ablocks[--a];
|
|
bh = sb_getblk(inode->i_sb, (ext4_fsblk_t)newblock);
|
|
if (!bh) {
|
|
err = -EIO;
|
|
goto cleanup;
|
|
}
|
|
lock_buffer(bh);
|
|
|
|
if ((err = ext4_journal_get_create_access(handle, bh)))
|
|
goto cleanup;
|
|
|
|
neh = ext_block_hdr(bh);
|
|
neh->eh_entries = cpu_to_le16(1);
|
|
neh->eh_magic = EXT4_EXT_MAGIC;
|
|
neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode));
|
|
neh->eh_depth = cpu_to_le16(depth - i);
|
|
fidx = EXT_FIRST_INDEX(neh);
|
|
fidx->ei_block = border;
|
|
ext4_idx_store_pblock(fidx, oldblock);
|
|
|
|
ext_debug("int.index at %d (block %llu): %lu -> %llu\n", i,
|
|
newblock, (unsigned long) le32_to_cpu(border),
|
|
oldblock);
|
|
/* copy indexes */
|
|
m = 0;
|
|
path[i].p_idx++;
|
|
|
|
ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
|
|
EXT_MAX_INDEX(path[i].p_hdr));
|
|
BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) !=
|
|
EXT_LAST_INDEX(path[i].p_hdr));
|
|
while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
|
|
ext_debug("%d: move %d:%d in new index %llu\n", i,
|
|
le32_to_cpu(path[i].p_idx->ei_block),
|
|
idx_pblock(path[i].p_idx),
|
|
newblock);
|
|
/*memmove(++fidx, path[i].p_idx++,
|
|
sizeof(struct ext4_extent_idx));
|
|
neh->eh_entries++;
|
|
BUG_ON(neh->eh_entries > neh->eh_max);*/
|
|
path[i].p_idx++;
|
|
m++;
|
|
}
|
|
if (m) {
|
|
memmove(++fidx, path[i].p_idx - m,
|
|
sizeof(struct ext4_extent_idx) * m);
|
|
neh->eh_entries =
|
|
cpu_to_le16(le16_to_cpu(neh->eh_entries) + m);
|
|
}
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
|
|
if ((err = ext4_journal_dirty_metadata(handle, bh)))
|
|
goto cleanup;
|
|
brelse(bh);
|
|
bh = NULL;
|
|
|
|
/* correct old index */
|
|
if (m) {
|
|
err = ext4_ext_get_access(handle, inode, path + i);
|
|
if (err)
|
|
goto cleanup;
|
|
path[i].p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path[i].p_hdr->eh_entries)-m);
|
|
err = ext4_ext_dirty(handle, inode, path + i);
|
|
if (err)
|
|
goto cleanup;
|
|
}
|
|
|
|
i--;
|
|
}
|
|
|
|
/* insert new index */
|
|
if (err)
|
|
goto cleanup;
|
|
|
|
err = ext4_ext_insert_index(handle, inode, path + at,
|
|
le32_to_cpu(border), newblock);
|
|
|
|
cleanup:
|
|
if (bh) {
|
|
if (buffer_locked(bh))
|
|
unlock_buffer(bh);
|
|
brelse(bh);
|
|
}
|
|
|
|
if (err) {
|
|
/* free all allocated blocks in error case */
|
|
for (i = 0; i < depth; i++) {
|
|
if (!ablocks[i])
|
|
continue;
|
|
ext4_free_blocks(handle, inode, ablocks[i], 1);
|
|
}
|
|
}
|
|
kfree(ablocks);
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_grow_indepth:
|
|
* implements tree growing procedure:
|
|
* - allocates new block
|
|
* - moves top-level data (index block or leaf) into the new block
|
|
* - initializes new top-level, creating index that points to the
|
|
* just created block
|
|
*/
|
|
static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path,
|
|
struct ext4_extent *newext)
|
|
{
|
|
struct ext4_ext_path *curp = path;
|
|
struct ext4_extent_header *neh;
|
|
struct ext4_extent_idx *fidx;
|
|
struct buffer_head *bh;
|
|
ext4_fsblk_t newblock;
|
|
int err = 0;
|
|
|
|
newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
|
|
if (newblock == 0)
|
|
return err;
|
|
|
|
bh = sb_getblk(inode->i_sb, newblock);
|
|
if (!bh) {
|
|
err = -EIO;
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
lock_buffer(bh);
|
|
|
|
if ((err = ext4_journal_get_create_access(handle, bh))) {
|
|
unlock_buffer(bh);
|
|
goto out;
|
|
}
|
|
|
|
/* move top-level index/leaf into new block */
|
|
memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data));
|
|
|
|
/* set size of new block */
|
|
neh = ext_block_hdr(bh);
|
|
/* old root could have indexes or leaves
|
|
* so calculate e_max right way */
|
|
if (ext_depth(inode))
|
|
neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode));
|
|
else
|
|
neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode));
|
|
neh->eh_magic = EXT4_EXT_MAGIC;
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
|
|
if ((err = ext4_journal_dirty_metadata(handle, bh)))
|
|
goto out;
|
|
|
|
/* create index in new top-level index: num,max,pointer */
|
|
if ((err = ext4_ext_get_access(handle, inode, curp)))
|
|
goto out;
|
|
|
|
curp->p_hdr->eh_magic = EXT4_EXT_MAGIC;
|
|
curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode));
|
|
curp->p_hdr->eh_entries = cpu_to_le16(1);
|
|
curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
|
|
/* FIXME: it works, but actually path[0] can be index */
|
|
curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
|
|
ext4_idx_store_pblock(curp->p_idx, newblock);
|
|
|
|
neh = ext_inode_hdr(inode);
|
|
fidx = EXT_FIRST_INDEX(neh);
|
|
ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
|
|
le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
|
|
le32_to_cpu(fidx->ei_block), idx_pblock(fidx));
|
|
|
|
neh->eh_depth = cpu_to_le16(path->p_depth + 1);
|
|
err = ext4_ext_dirty(handle, inode, curp);
|
|
out:
|
|
brelse(bh);
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_create_new_leaf:
|
|
* finds empty index and adds new leaf.
|
|
* if no free index is found, then it requests in-depth growing.
|
|
*/
|
|
static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path,
|
|
struct ext4_extent *newext)
|
|
{
|
|
struct ext4_ext_path *curp;
|
|
int depth, i, err = 0;
|
|
|
|
repeat:
|
|
i = depth = ext_depth(inode);
|
|
|
|
/* walk up to the tree and look for free index entry */
|
|
curp = path + depth;
|
|
while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
|
|
i--;
|
|
curp--;
|
|
}
|
|
|
|
/* we use already allocated block for index block,
|
|
* so subsequent data blocks should be contiguous */
|
|
if (EXT_HAS_FREE_INDEX(curp)) {
|
|
/* if we found index with free entry, then use that
|
|
* entry: create all needed subtree and add new leaf */
|
|
err = ext4_ext_split(handle, inode, path, newext, i);
|
|
|
|
/* refill path */
|
|
ext4_ext_drop_refs(path);
|
|
path = ext4_ext_find_extent(inode,
|
|
le32_to_cpu(newext->ee_block),
|
|
path);
|
|
if (IS_ERR(path))
|
|
err = PTR_ERR(path);
|
|
} else {
|
|
/* tree is full, time to grow in depth */
|
|
err = ext4_ext_grow_indepth(handle, inode, path, newext);
|
|
if (err)
|
|
goto out;
|
|
|
|
/* refill path */
|
|
ext4_ext_drop_refs(path);
|
|
path = ext4_ext_find_extent(inode,
|
|
le32_to_cpu(newext->ee_block),
|
|
path);
|
|
if (IS_ERR(path)) {
|
|
err = PTR_ERR(path);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* only first (depth 0 -> 1) produces free space;
|
|
* in all other cases we have to split the grown tree
|
|
*/
|
|
depth = ext_depth(inode);
|
|
if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
|
|
/* now we need to split */
|
|
goto repeat;
|
|
}
|
|
}
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_next_allocated_block:
|
|
* returns allocated block in subsequent extent or EXT_MAX_BLOCK.
|
|
* NOTE: it considers block number from index entry as
|
|
* allocated block. Thus, index entries have to be consistent
|
|
* with leaves.
|
|
*/
|
|
static unsigned long
|
|
ext4_ext_next_allocated_block(struct ext4_ext_path *path)
|
|
{
|
|
int depth;
|
|
|
|
BUG_ON(path == NULL);
|
|
depth = path->p_depth;
|
|
|
|
if (depth == 0 && path->p_ext == NULL)
|
|
return EXT_MAX_BLOCK;
|
|
|
|
while (depth >= 0) {
|
|
if (depth == path->p_depth) {
|
|
/* leaf */
|
|
if (path[depth].p_ext !=
|
|
EXT_LAST_EXTENT(path[depth].p_hdr))
|
|
return le32_to_cpu(path[depth].p_ext[1].ee_block);
|
|
} else {
|
|
/* index */
|
|
if (path[depth].p_idx !=
|
|
EXT_LAST_INDEX(path[depth].p_hdr))
|
|
return le32_to_cpu(path[depth].p_idx[1].ei_block);
|
|
}
|
|
depth--;
|
|
}
|
|
|
|
return EXT_MAX_BLOCK;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_next_leaf_block:
|
|
* returns first allocated block from next leaf or EXT_MAX_BLOCK
|
|
*/
|
|
static unsigned ext4_ext_next_leaf_block(struct inode *inode,
|
|
struct ext4_ext_path *path)
|
|
{
|
|
int depth;
|
|
|
|
BUG_ON(path == NULL);
|
|
depth = path->p_depth;
|
|
|
|
/* zero-tree has no leaf blocks at all */
|
|
if (depth == 0)
|
|
return EXT_MAX_BLOCK;
|
|
|
|
/* go to index block */
|
|
depth--;
|
|
|
|
while (depth >= 0) {
|
|
if (path[depth].p_idx !=
|
|
EXT_LAST_INDEX(path[depth].p_hdr))
|
|
return le32_to_cpu(path[depth].p_idx[1].ei_block);
|
|
depth--;
|
|
}
|
|
|
|
return EXT_MAX_BLOCK;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_correct_indexes:
|
|
* if leaf gets modified and modified extent is first in the leaf,
|
|
* then we have to correct all indexes above.
|
|
* TODO: do we need to correct tree in all cases?
|
|
*/
|
|
int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path)
|
|
{
|
|
struct ext4_extent_header *eh;
|
|
int depth = ext_depth(inode);
|
|
struct ext4_extent *ex;
|
|
__le32 border;
|
|
int k, err = 0;
|
|
|
|
eh = path[depth].p_hdr;
|
|
ex = path[depth].p_ext;
|
|
BUG_ON(ex == NULL);
|
|
BUG_ON(eh == NULL);
|
|
|
|
if (depth == 0) {
|
|
/* there is no tree at all */
|
|
return 0;
|
|
}
|
|
|
|
if (ex != EXT_FIRST_EXTENT(eh)) {
|
|
/* we correct tree if first leaf got modified only */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* TODO: we need correction if border is smaller than current one
|
|
*/
|
|
k = depth - 1;
|
|
border = path[depth].p_ext->ee_block;
|
|
if ((err = ext4_ext_get_access(handle, inode, path + k)))
|
|
return err;
|
|
path[k].p_idx->ei_block = border;
|
|
if ((err = ext4_ext_dirty(handle, inode, path + k)))
|
|
return err;
|
|
|
|
while (k--) {
|
|
/* change all left-side indexes */
|
|
if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
|
|
break;
|
|
if ((err = ext4_ext_get_access(handle, inode, path + k)))
|
|
break;
|
|
path[k].p_idx->ei_block = border;
|
|
if ((err = ext4_ext_dirty(handle, inode, path + k)))
|
|
break;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int inline
|
|
ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
|
|
struct ext4_extent *ex2)
|
|
{
|
|
if (le32_to_cpu(ex1->ee_block) + le16_to_cpu(ex1->ee_len) !=
|
|
le32_to_cpu(ex2->ee_block))
|
|
return 0;
|
|
|
|
/*
|
|
* To allow future support for preallocated extents to be added
|
|
* as an RO_COMPAT feature, refuse to merge to extents if
|
|
* this can result in the top bit of ee_len being set.
|
|
*/
|
|
if (le16_to_cpu(ex1->ee_len) + le16_to_cpu(ex2->ee_len) > EXT_MAX_LEN)
|
|
return 0;
|
|
#ifdef AGRESSIVE_TEST
|
|
if (le16_to_cpu(ex1->ee_len) >= 4)
|
|
return 0;
|
|
#endif
|
|
|
|
if (ext_pblock(ex1) + le16_to_cpu(ex1->ee_len) == ext_pblock(ex2))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_insert_extent:
|
|
* tries to merge requsted extent into the existing extent or
|
|
* inserts requested extent as new one into the tree,
|
|
* creating new leaf in the no-space case.
|
|
*/
|
|
int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path,
|
|
struct ext4_extent *newext)
|
|
{
|
|
struct ext4_extent_header * eh;
|
|
struct ext4_extent *ex, *fex;
|
|
struct ext4_extent *nearex; /* nearest extent */
|
|
struct ext4_ext_path *npath = NULL;
|
|
int depth, len, err, next;
|
|
|
|
BUG_ON(newext->ee_len == 0);
|
|
depth = ext_depth(inode);
|
|
ex = path[depth].p_ext;
|
|
BUG_ON(path[depth].p_hdr == NULL);
|
|
|
|
/* try to insert block into found extent and return */
|
|
if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
|
|
ext_debug("append %d block to %d:%d (from %llu)\n",
|
|
le16_to_cpu(newext->ee_len),
|
|
le32_to_cpu(ex->ee_block),
|
|
le16_to_cpu(ex->ee_len), ext_pblock(ex));
|
|
if ((err = ext4_ext_get_access(handle, inode, path + depth)))
|
|
return err;
|
|
ex->ee_len = cpu_to_le16(le16_to_cpu(ex->ee_len)
|
|
+ le16_to_cpu(newext->ee_len));
|
|
eh = path[depth].p_hdr;
|
|
nearex = ex;
|
|
goto merge;
|
|
}
|
|
|
|
repeat:
|
|
depth = ext_depth(inode);
|
|
eh = path[depth].p_hdr;
|
|
if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
|
|
goto has_space;
|
|
|
|
/* probably next leaf has space for us? */
|
|
fex = EXT_LAST_EXTENT(eh);
|
|
next = ext4_ext_next_leaf_block(inode, path);
|
|
if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)
|
|
&& next != EXT_MAX_BLOCK) {
|
|
ext_debug("next leaf block - %d\n", next);
|
|
BUG_ON(npath != NULL);
|
|
npath = ext4_ext_find_extent(inode, next, NULL);
|
|
if (IS_ERR(npath))
|
|
return PTR_ERR(npath);
|
|
BUG_ON(npath->p_depth != path->p_depth);
|
|
eh = npath[depth].p_hdr;
|
|
if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
|
|
ext_debug("next leaf isnt full(%d)\n",
|
|
le16_to_cpu(eh->eh_entries));
|
|
path = npath;
|
|
goto repeat;
|
|
}
|
|
ext_debug("next leaf has no free space(%d,%d)\n",
|
|
le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
|
|
}
|
|
|
|
/*
|
|
* There is no free space in the found leaf.
|
|
* We're gonna add a new leaf in the tree.
|
|
*/
|
|
err = ext4_ext_create_new_leaf(handle, inode, path, newext);
|
|
if (err)
|
|
goto cleanup;
|
|
depth = ext_depth(inode);
|
|
eh = path[depth].p_hdr;
|
|
|
|
has_space:
|
|
nearex = path[depth].p_ext;
|
|
|
|
if ((err = ext4_ext_get_access(handle, inode, path + depth)))
|
|
goto cleanup;
|
|
|
|
if (!nearex) {
|
|
/* there is no extent in this leaf, create first one */
|
|
ext_debug("first extent in the leaf: %d:%llu:%d\n",
|
|
le32_to_cpu(newext->ee_block),
|
|
ext_pblock(newext),
|
|
le16_to_cpu(newext->ee_len));
|
|
path[depth].p_ext = EXT_FIRST_EXTENT(eh);
|
|
} else if (le32_to_cpu(newext->ee_block)
|
|
> le32_to_cpu(nearex->ee_block)) {
|
|
/* BUG_ON(newext->ee_block == nearex->ee_block); */
|
|
if (nearex != EXT_LAST_EXTENT(eh)) {
|
|
len = EXT_MAX_EXTENT(eh) - nearex;
|
|
len = (len - 1) * sizeof(struct ext4_extent);
|
|
len = len < 0 ? 0 : len;
|
|
ext_debug("insert %d:%llu:%d after: nearest 0x%p, "
|
|
"move %d from 0x%p to 0x%p\n",
|
|
le32_to_cpu(newext->ee_block),
|
|
ext_pblock(newext),
|
|
le16_to_cpu(newext->ee_len),
|
|
nearex, len, nearex + 1, nearex + 2);
|
|
memmove(nearex + 2, nearex + 1, len);
|
|
}
|
|
path[depth].p_ext = nearex + 1;
|
|
} else {
|
|
BUG_ON(newext->ee_block == nearex->ee_block);
|
|
len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent);
|
|
len = len < 0 ? 0 : len;
|
|
ext_debug("insert %d:%llu:%d before: nearest 0x%p, "
|
|
"move %d from 0x%p to 0x%p\n",
|
|
le32_to_cpu(newext->ee_block),
|
|
ext_pblock(newext),
|
|
le16_to_cpu(newext->ee_len),
|
|
nearex, len, nearex + 1, nearex + 2);
|
|
memmove(nearex + 1, nearex, len);
|
|
path[depth].p_ext = nearex;
|
|
}
|
|
|
|
eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1);
|
|
nearex = path[depth].p_ext;
|
|
nearex->ee_block = newext->ee_block;
|
|
nearex->ee_start = newext->ee_start;
|
|
nearex->ee_start_hi = newext->ee_start_hi;
|
|
nearex->ee_len = newext->ee_len;
|
|
|
|
merge:
|
|
/* try to merge extents to the right */
|
|
while (nearex < EXT_LAST_EXTENT(eh)) {
|
|
if (!ext4_can_extents_be_merged(inode, nearex, nearex + 1))
|
|
break;
|
|
/* merge with next extent! */
|
|
nearex->ee_len = cpu_to_le16(le16_to_cpu(nearex->ee_len)
|
|
+ le16_to_cpu(nearex[1].ee_len));
|
|
if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
|
|
len = (EXT_LAST_EXTENT(eh) - nearex - 1)
|
|
* sizeof(struct ext4_extent);
|
|
memmove(nearex + 1, nearex + 2, len);
|
|
}
|
|
eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
|
|
BUG_ON(eh->eh_entries == 0);
|
|
}
|
|
|
|
/* try to merge extents to the left */
|
|
|
|
/* time to correct all indexes above */
|
|
err = ext4_ext_correct_indexes(handle, inode, path);
|
|
if (err)
|
|
goto cleanup;
|
|
|
|
err = ext4_ext_dirty(handle, inode, path + depth);
|
|
|
|
cleanup:
|
|
if (npath) {
|
|
ext4_ext_drop_refs(npath);
|
|
kfree(npath);
|
|
}
|
|
ext4_ext_tree_changed(inode);
|
|
ext4_ext_invalidate_cache(inode);
|
|
return err;
|
|
}
|
|
|
|
int ext4_ext_walk_space(struct inode *inode, unsigned long block,
|
|
unsigned long num, ext_prepare_callback func,
|
|
void *cbdata)
|
|
{
|
|
struct ext4_ext_path *path = NULL;
|
|
struct ext4_ext_cache cbex;
|
|
struct ext4_extent *ex;
|
|
unsigned long next, start = 0, end = 0;
|
|
unsigned long last = block + num;
|
|
int depth, exists, err = 0;
|
|
|
|
BUG_ON(func == NULL);
|
|
BUG_ON(inode == NULL);
|
|
|
|
while (block < last && block != EXT_MAX_BLOCK) {
|
|
num = last - block;
|
|
/* find extent for this block */
|
|
path = ext4_ext_find_extent(inode, block, path);
|
|
if (IS_ERR(path)) {
|
|
err = PTR_ERR(path);
|
|
path = NULL;
|
|
break;
|
|
}
|
|
|
|
depth = ext_depth(inode);
|
|
BUG_ON(path[depth].p_hdr == NULL);
|
|
ex = path[depth].p_ext;
|
|
next = ext4_ext_next_allocated_block(path);
|
|
|
|
exists = 0;
|
|
if (!ex) {
|
|
/* there is no extent yet, so try to allocate
|
|
* all requested space */
|
|
start = block;
|
|
end = block + num;
|
|
} else if (le32_to_cpu(ex->ee_block) > block) {
|
|
/* need to allocate space before found extent */
|
|
start = block;
|
|
end = le32_to_cpu(ex->ee_block);
|
|
if (block + num < end)
|
|
end = block + num;
|
|
} else if (block >=
|
|
le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len)) {
|
|
/* need to allocate space after found extent */
|
|
start = block;
|
|
end = block + num;
|
|
if (end >= next)
|
|
end = next;
|
|
} else if (block >= le32_to_cpu(ex->ee_block)) {
|
|
/*
|
|
* some part of requested space is covered
|
|
* by found extent
|
|
*/
|
|
start = block;
|
|
end = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len);
|
|
if (block + num < end)
|
|
end = block + num;
|
|
exists = 1;
|
|
} else {
|
|
BUG();
|
|
}
|
|
BUG_ON(end <= start);
|
|
|
|
if (!exists) {
|
|
cbex.ec_block = start;
|
|
cbex.ec_len = end - start;
|
|
cbex.ec_start = 0;
|
|
cbex.ec_type = EXT4_EXT_CACHE_GAP;
|
|
} else {
|
|
cbex.ec_block = le32_to_cpu(ex->ee_block);
|
|
cbex.ec_len = le16_to_cpu(ex->ee_len);
|
|
cbex.ec_start = ext_pblock(ex);
|
|
cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
|
|
}
|
|
|
|
BUG_ON(cbex.ec_len == 0);
|
|
err = func(inode, path, &cbex, cbdata);
|
|
ext4_ext_drop_refs(path);
|
|
|
|
if (err < 0)
|
|
break;
|
|
if (err == EXT_REPEAT)
|
|
continue;
|
|
else if (err == EXT_BREAK) {
|
|
err = 0;
|
|
break;
|
|
}
|
|
|
|
if (ext_depth(inode) != depth) {
|
|
/* depth was changed. we have to realloc path */
|
|
kfree(path);
|
|
path = NULL;
|
|
}
|
|
|
|
block = cbex.ec_block + cbex.ec_len;
|
|
}
|
|
|
|
if (path) {
|
|
ext4_ext_drop_refs(path);
|
|
kfree(path);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static inline void
|
|
ext4_ext_put_in_cache(struct inode *inode, __u32 block,
|
|
__u32 len, __u32 start, int type)
|
|
{
|
|
struct ext4_ext_cache *cex;
|
|
BUG_ON(len == 0);
|
|
cex = &EXT4_I(inode)->i_cached_extent;
|
|
cex->ec_type = type;
|
|
cex->ec_block = block;
|
|
cex->ec_len = len;
|
|
cex->ec_start = start;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_put_gap_in_cache:
|
|
* calculate boundaries of the gap that the requested block fits into
|
|
* and cache this gap
|
|
*/
|
|
static inline void
|
|
ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
|
|
unsigned long block)
|
|
{
|
|
int depth = ext_depth(inode);
|
|
unsigned long lblock, len;
|
|
struct ext4_extent *ex;
|
|
|
|
ex = path[depth].p_ext;
|
|
if (ex == NULL) {
|
|
/* there is no extent yet, so gap is [0;-] */
|
|
lblock = 0;
|
|
len = EXT_MAX_BLOCK;
|
|
ext_debug("cache gap(whole file):");
|
|
} else if (block < le32_to_cpu(ex->ee_block)) {
|
|
lblock = block;
|
|
len = le32_to_cpu(ex->ee_block) - block;
|
|
ext_debug("cache gap(before): %lu [%lu:%lu]",
|
|
(unsigned long) block,
|
|
(unsigned long) le32_to_cpu(ex->ee_block),
|
|
(unsigned long) le16_to_cpu(ex->ee_len));
|
|
} else if (block >= le32_to_cpu(ex->ee_block)
|
|
+ le16_to_cpu(ex->ee_len)) {
|
|
lblock = le32_to_cpu(ex->ee_block)
|
|
+ le16_to_cpu(ex->ee_len);
|
|
len = ext4_ext_next_allocated_block(path);
|
|
ext_debug("cache gap(after): [%lu:%lu] %lu",
|
|
(unsigned long) le32_to_cpu(ex->ee_block),
|
|
(unsigned long) le16_to_cpu(ex->ee_len),
|
|
(unsigned long) block);
|
|
BUG_ON(len == lblock);
|
|
len = len - lblock;
|
|
} else {
|
|
lblock = len = 0;
|
|
BUG();
|
|
}
|
|
|
|
ext_debug(" -> %lu:%lu\n", (unsigned long) lblock, len);
|
|
ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP);
|
|
}
|
|
|
|
static inline int
|
|
ext4_ext_in_cache(struct inode *inode, unsigned long block,
|
|
struct ext4_extent *ex)
|
|
{
|
|
struct ext4_ext_cache *cex;
|
|
|
|
cex = &EXT4_I(inode)->i_cached_extent;
|
|
|
|
/* has cache valid data? */
|
|
if (cex->ec_type == EXT4_EXT_CACHE_NO)
|
|
return EXT4_EXT_CACHE_NO;
|
|
|
|
BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP &&
|
|
cex->ec_type != EXT4_EXT_CACHE_EXTENT);
|
|
if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
|
|
ex->ee_block = cpu_to_le32(cex->ec_block);
|
|
ext4_ext_store_pblock(ex, cex->ec_start);
|
|
ex->ee_len = cpu_to_le16(cex->ec_len);
|
|
ext_debug("%lu cached by %lu:%lu:%llu\n",
|
|
(unsigned long) block,
|
|
(unsigned long) cex->ec_block,
|
|
(unsigned long) cex->ec_len,
|
|
cex->ec_start);
|
|
return cex->ec_type;
|
|
}
|
|
|
|
/* not in cache */
|
|
return EXT4_EXT_CACHE_NO;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_rm_idx:
|
|
* removes index from the index block.
|
|
* It's used in truncate case only, thus all requests are for
|
|
* last index in the block only.
|
|
*/
|
|
int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path)
|
|
{
|
|
struct buffer_head *bh;
|
|
int err;
|
|
ext4_fsblk_t leaf;
|
|
|
|
/* free index block */
|
|
path--;
|
|
leaf = idx_pblock(path->p_idx);
|
|
BUG_ON(path->p_hdr->eh_entries == 0);
|
|
if ((err = ext4_ext_get_access(handle, inode, path)))
|
|
return err;
|
|
path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1);
|
|
if ((err = ext4_ext_dirty(handle, inode, path)))
|
|
return err;
|
|
ext_debug("index is empty, remove it, free block %llu\n", leaf);
|
|
bh = sb_find_get_block(inode->i_sb, leaf);
|
|
ext4_forget(handle, 1, inode, bh, leaf);
|
|
ext4_free_blocks(handle, inode, leaf, 1);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_calc_credits_for_insert:
|
|
* This routine returns max. credits that the extent tree can consume.
|
|
* It should be OK for low-performance paths like ->writepage()
|
|
* To allow many writing processes to fit into a single transaction,
|
|
* the caller should calculate credits under truncate_mutex and
|
|
* pass the actual path.
|
|
*/
|
|
int inline ext4_ext_calc_credits_for_insert(struct inode *inode,
|
|
struct ext4_ext_path *path)
|
|
{
|
|
int depth, needed;
|
|
|
|
if (path) {
|
|
/* probably there is space in leaf? */
|
|
depth = ext_depth(inode);
|
|
if (le16_to_cpu(path[depth].p_hdr->eh_entries)
|
|
< le16_to_cpu(path[depth].p_hdr->eh_max))
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* given 32-bit logical block (4294967296 blocks), max. tree
|
|
* can be 4 levels in depth -- 4 * 340^4 == 53453440000.
|
|
* Let's also add one more level for imbalance.
|
|
*/
|
|
depth = 5;
|
|
|
|
/* allocation of new data block(s) */
|
|
needed = 2;
|
|
|
|
/*
|
|
* tree can be full, so it would need to grow in depth:
|
|
* allocation + old root + new root
|
|
*/
|
|
needed += 2 + 1 + 1;
|
|
|
|
/*
|
|
* Index split can happen, we would need:
|
|
* allocate intermediate indexes (bitmap + group)
|
|
* + change two blocks at each level, but root (already included)
|
|
*/
|
|
needed = (depth * 2) + (depth * 2);
|
|
|
|
/* any allocation modifies superblock */
|
|
needed += 1;
|
|
|
|
return needed;
|
|
}
|
|
|
|
static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
|
|
struct ext4_extent *ex,
|
|
unsigned long from, unsigned long to)
|
|
{
|
|
struct buffer_head *bh;
|
|
int i;
|
|
|
|
#ifdef EXTENTS_STATS
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
unsigned short ee_len = le16_to_cpu(ex->ee_len);
|
|
spin_lock(&sbi->s_ext_stats_lock);
|
|
sbi->s_ext_blocks += ee_len;
|
|
sbi->s_ext_extents++;
|
|
if (ee_len < sbi->s_ext_min)
|
|
sbi->s_ext_min = ee_len;
|
|
if (ee_len > sbi->s_ext_max)
|
|
sbi->s_ext_max = ee_len;
|
|
if (ext_depth(inode) > sbi->s_depth_max)
|
|
sbi->s_depth_max = ext_depth(inode);
|
|
spin_unlock(&sbi->s_ext_stats_lock);
|
|
}
|
|
#endif
|
|
if (from >= le32_to_cpu(ex->ee_block)
|
|
&& to == le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) {
|
|
/* tail removal */
|
|
unsigned long num;
|
|
ext4_fsblk_t start;
|
|
num = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - from;
|
|
start = ext_pblock(ex) + le16_to_cpu(ex->ee_len) - num;
|
|
ext_debug("free last %lu blocks starting %llu\n", num, start);
|
|
for (i = 0; i < num; i++) {
|
|
bh = sb_find_get_block(inode->i_sb, start + i);
|
|
ext4_forget(handle, 0, inode, bh, start + i);
|
|
}
|
|
ext4_free_blocks(handle, inode, start, num);
|
|
} else if (from == le32_to_cpu(ex->ee_block)
|
|
&& to <= le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) {
|
|
printk("strange request: removal %lu-%lu from %u:%u\n",
|
|
from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len));
|
|
} else {
|
|
printk("strange request: removal(2) %lu-%lu from %u:%u\n",
|
|
from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len));
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
|
|
struct ext4_ext_path *path, unsigned long start)
|
|
{
|
|
int err = 0, correct_index = 0;
|
|
int depth = ext_depth(inode), credits;
|
|
struct ext4_extent_header *eh;
|
|
unsigned a, b, block, num;
|
|
unsigned long ex_ee_block;
|
|
unsigned short ex_ee_len;
|
|
struct ext4_extent *ex;
|
|
|
|
ext_debug("truncate since %lu in leaf\n", start);
|
|
if (!path[depth].p_hdr)
|
|
path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
|
|
eh = path[depth].p_hdr;
|
|
BUG_ON(eh == NULL);
|
|
BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
|
|
BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
|
|
|
|
/* find where to start removing */
|
|
ex = EXT_LAST_EXTENT(eh);
|
|
|
|
ex_ee_block = le32_to_cpu(ex->ee_block);
|
|
ex_ee_len = le16_to_cpu(ex->ee_len);
|
|
|
|
while (ex >= EXT_FIRST_EXTENT(eh) &&
|
|
ex_ee_block + ex_ee_len > start) {
|
|
ext_debug("remove ext %lu:%u\n", ex_ee_block, ex_ee_len);
|
|
path[depth].p_ext = ex;
|
|
|
|
a = ex_ee_block > start ? ex_ee_block : start;
|
|
b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ?
|
|
ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK;
|
|
|
|
ext_debug(" border %u:%u\n", a, b);
|
|
|
|
if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) {
|
|
block = 0;
|
|
num = 0;
|
|
BUG();
|
|
} else if (a != ex_ee_block) {
|
|
/* remove tail of the extent */
|
|
block = ex_ee_block;
|
|
num = a - block;
|
|
} else if (b != ex_ee_block + ex_ee_len - 1) {
|
|
/* remove head of the extent */
|
|
block = a;
|
|
num = b - a;
|
|
/* there is no "make a hole" API yet */
|
|
BUG();
|
|
} else {
|
|
/* remove whole extent: excellent! */
|
|
block = ex_ee_block;
|
|
num = 0;
|
|
BUG_ON(a != ex_ee_block);
|
|
BUG_ON(b != ex_ee_block + ex_ee_len - 1);
|
|
}
|
|
|
|
/* at present, extent can't cross block group: */
|
|
/* leaf + bitmap + group desc + sb + inode */
|
|
credits = 5;
|
|
if (ex == EXT_FIRST_EXTENT(eh)) {
|
|
correct_index = 1;
|
|
credits += (ext_depth(inode)) + 1;
|
|
}
|
|
#ifdef CONFIG_QUOTA
|
|
credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
|
|
#endif
|
|
|
|
handle = ext4_ext_journal_restart(handle, credits);
|
|
if (IS_ERR(handle)) {
|
|
err = PTR_ERR(handle);
|
|
goto out;
|
|
}
|
|
|
|
err = ext4_ext_get_access(handle, inode, path + depth);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = ext4_remove_blocks(handle, inode, ex, a, b);
|
|
if (err)
|
|
goto out;
|
|
|
|
if (num == 0) {
|
|
/* this extent is removed; mark slot entirely unused */
|
|
ext4_ext_store_pblock(ex, 0);
|
|
eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
|
|
}
|
|
|
|
ex->ee_block = cpu_to_le32(block);
|
|
ex->ee_len = cpu_to_le16(num);
|
|
|
|
err = ext4_ext_dirty(handle, inode, path + depth);
|
|
if (err)
|
|
goto out;
|
|
|
|
ext_debug("new extent: %u:%u:%llu\n", block, num,
|
|
ext_pblock(ex));
|
|
ex--;
|
|
ex_ee_block = le32_to_cpu(ex->ee_block);
|
|
ex_ee_len = le16_to_cpu(ex->ee_len);
|
|
}
|
|
|
|
if (correct_index && eh->eh_entries)
|
|
err = ext4_ext_correct_indexes(handle, inode, path);
|
|
|
|
/* if this leaf is free, then we should
|
|
* remove it from index block above */
|
|
if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
|
|
err = ext4_ext_rm_idx(handle, inode, path + depth);
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_more_to_rm:
|
|
* returns 1 if current index has to be freed (even partial)
|
|
*/
|
|
static int inline
|
|
ext4_ext_more_to_rm(struct ext4_ext_path *path)
|
|
{
|
|
BUG_ON(path->p_idx == NULL);
|
|
|
|
if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
|
|
return 0;
|
|
|
|
/*
|
|
* if truncate on deeper level happened, it wasn't partial,
|
|
* so we have to consider current index for truncation
|
|
*/
|
|
if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
int ext4_ext_remove_space(struct inode *inode, unsigned long start)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
int depth = ext_depth(inode);
|
|
struct ext4_ext_path *path;
|
|
handle_t *handle;
|
|
int i = 0, err = 0;
|
|
|
|
ext_debug("truncate since %lu\n", start);
|
|
|
|
/* probably first extent we're gonna free will be last in block */
|
|
handle = ext4_journal_start(inode, depth + 1);
|
|
if (IS_ERR(handle))
|
|
return PTR_ERR(handle);
|
|
|
|
ext4_ext_invalidate_cache(inode);
|
|
|
|
/*
|
|
* We start scanning from right side, freeing all the blocks
|
|
* after i_size and walking into the tree depth-wise.
|
|
*/
|
|
path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL);
|
|
if (path == NULL) {
|
|
ext4_journal_stop(handle);
|
|
return -ENOMEM;
|
|
}
|
|
memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1));
|
|
path[0].p_hdr = ext_inode_hdr(inode);
|
|
if (ext4_ext_check_header(__FUNCTION__, inode, path[0].p_hdr)) {
|
|
err = -EIO;
|
|
goto out;
|
|
}
|
|
path[0].p_depth = depth;
|
|
|
|
while (i >= 0 && err == 0) {
|
|
if (i == depth) {
|
|
/* this is leaf block */
|
|
err = ext4_ext_rm_leaf(handle, inode, path, start);
|
|
/* root level has p_bh == NULL, brelse() eats this */
|
|
brelse(path[i].p_bh);
|
|
path[i].p_bh = NULL;
|
|
i--;
|
|
continue;
|
|
}
|
|
|
|
/* this is index block */
|
|
if (!path[i].p_hdr) {
|
|
ext_debug("initialize header\n");
|
|
path[i].p_hdr = ext_block_hdr(path[i].p_bh);
|
|
if (ext4_ext_check_header(__FUNCTION__, inode,
|
|
path[i].p_hdr)) {
|
|
err = -EIO;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
BUG_ON(le16_to_cpu(path[i].p_hdr->eh_entries)
|
|
> le16_to_cpu(path[i].p_hdr->eh_max));
|
|
BUG_ON(path[i].p_hdr->eh_magic != EXT4_EXT_MAGIC);
|
|
|
|
if (!path[i].p_idx) {
|
|
/* this level hasn't been touched yet */
|
|
path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
|
|
path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
|
|
ext_debug("init index ptr: hdr 0x%p, num %d\n",
|
|
path[i].p_hdr,
|
|
le16_to_cpu(path[i].p_hdr->eh_entries));
|
|
} else {
|
|
/* we were already here, see at next index */
|
|
path[i].p_idx--;
|
|
}
|
|
|
|
ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
|
|
i, EXT_FIRST_INDEX(path[i].p_hdr),
|
|
path[i].p_idx);
|
|
if (ext4_ext_more_to_rm(path + i)) {
|
|
/* go to the next level */
|
|
ext_debug("move to level %d (block %llu)\n",
|
|
i + 1, idx_pblock(path[i].p_idx));
|
|
memset(path + i + 1, 0, sizeof(*path));
|
|
path[i+1].p_bh =
|
|
sb_bread(sb, idx_pblock(path[i].p_idx));
|
|
if (!path[i+1].p_bh) {
|
|
/* should we reset i_size? */
|
|
err = -EIO;
|
|
break;
|
|
}
|
|
|
|
/* save actual number of indexes since this
|
|
* number is changed at the next iteration */
|
|
path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
|
|
i++;
|
|
} else {
|
|
/* we finished processing this index, go up */
|
|
if (path[i].p_hdr->eh_entries == 0 && i > 0) {
|
|
/* index is empty, remove it;
|
|
* handle must be already prepared by the
|
|
* truncatei_leaf() */
|
|
err = ext4_ext_rm_idx(handle, inode, path + i);
|
|
}
|
|
/* root level has p_bh == NULL, brelse() eats this */
|
|
brelse(path[i].p_bh);
|
|
path[i].p_bh = NULL;
|
|
i--;
|
|
ext_debug("return to level %d\n", i);
|
|
}
|
|
}
|
|
|
|
/* TODO: flexible tree reduction should be here */
|
|
if (path->p_hdr->eh_entries == 0) {
|
|
/*
|
|
* truncate to zero freed all the tree,
|
|
* so we need to correct eh_depth
|
|
*/
|
|
err = ext4_ext_get_access(handle, inode, path);
|
|
if (err == 0) {
|
|
ext_inode_hdr(inode)->eh_depth = 0;
|
|
ext_inode_hdr(inode)->eh_max =
|
|
cpu_to_le16(ext4_ext_space_root(inode));
|
|
err = ext4_ext_dirty(handle, inode, path);
|
|
}
|
|
}
|
|
out:
|
|
ext4_ext_tree_changed(inode);
|
|
ext4_ext_drop_refs(path);
|
|
kfree(path);
|
|
ext4_journal_stop(handle);
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* called at mount time
|
|
*/
|
|
void ext4_ext_init(struct super_block *sb)
|
|
{
|
|
/*
|
|
* possible initialization would be here
|
|
*/
|
|
|
|
if (test_opt(sb, EXTENTS)) {
|
|
printk("EXT4-fs: file extents enabled");
|
|
#ifdef AGRESSIVE_TEST
|
|
printk(", agressive tests");
|
|
#endif
|
|
#ifdef CHECK_BINSEARCH
|
|
printk(", check binsearch");
|
|
#endif
|
|
#ifdef EXTENTS_STATS
|
|
printk(", stats");
|
|
#endif
|
|
printk("\n");
|
|
#ifdef EXTENTS_STATS
|
|
spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
|
|
EXT4_SB(sb)->s_ext_min = 1 << 30;
|
|
EXT4_SB(sb)->s_ext_max = 0;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/*
|
|
* called at umount time
|
|
*/
|
|
void ext4_ext_release(struct super_block *sb)
|
|
{
|
|
if (!test_opt(sb, EXTENTS))
|
|
return;
|
|
|
|
#ifdef EXTENTS_STATS
|
|
if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
|
|
struct ext4_sb_info *sbi = EXT4_SB(sb);
|
|
printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
|
|
sbi->s_ext_blocks, sbi->s_ext_extents,
|
|
sbi->s_ext_blocks / sbi->s_ext_extents);
|
|
printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
|
|
sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
|
|
ext4_fsblk_t iblock,
|
|
unsigned long max_blocks, struct buffer_head *bh_result,
|
|
int create, int extend_disksize)
|
|
{
|
|
struct ext4_ext_path *path = NULL;
|
|
struct ext4_extent newex, *ex;
|
|
ext4_fsblk_t goal, newblock;
|
|
int err = 0, depth;
|
|
unsigned long allocated = 0;
|
|
|
|
__clear_bit(BH_New, &bh_result->b_state);
|
|
ext_debug("blocks %d/%lu requested for inode %u\n", (int) iblock,
|
|
max_blocks, (unsigned) inode->i_ino);
|
|
mutex_lock(&EXT4_I(inode)->truncate_mutex);
|
|
|
|
/* check in cache */
|
|
if ((goal = ext4_ext_in_cache(inode, iblock, &newex))) {
|
|
if (goal == EXT4_EXT_CACHE_GAP) {
|
|
if (!create) {
|
|
/* block isn't allocated yet and
|
|
* user doesn't want to allocate it */
|
|
goto out2;
|
|
}
|
|
/* we should allocate requested block */
|
|
} else if (goal == EXT4_EXT_CACHE_EXTENT) {
|
|
/* block is already allocated */
|
|
newblock = iblock
|
|
- le32_to_cpu(newex.ee_block)
|
|
+ ext_pblock(&newex);
|
|
/* number of remaining blocks in the extent */
|
|
allocated = le16_to_cpu(newex.ee_len) -
|
|
(iblock - le32_to_cpu(newex.ee_block));
|
|
goto out;
|
|
} else {
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
/* find extent for this block */
|
|
path = ext4_ext_find_extent(inode, iblock, NULL);
|
|
if (IS_ERR(path)) {
|
|
err = PTR_ERR(path);
|
|
path = NULL;
|
|
goto out2;
|
|
}
|
|
|
|
depth = ext_depth(inode);
|
|
|
|
/*
|
|
* consistent leaf must not be empty;
|
|
* this situation is possible, though, _during_ tree modification;
|
|
* this is why assert can't be put in ext4_ext_find_extent()
|
|
*/
|
|
BUG_ON(path[depth].p_ext == NULL && depth != 0);
|
|
|
|
if ((ex = path[depth].p_ext)) {
|
|
unsigned long ee_block = le32_to_cpu(ex->ee_block);
|
|
ext4_fsblk_t ee_start = ext_pblock(ex);
|
|
unsigned short ee_len = le16_to_cpu(ex->ee_len);
|
|
|
|
/*
|
|
* Allow future support for preallocated extents to be added
|
|
* as an RO_COMPAT feature:
|
|
* Uninitialized extents are treated as holes, except that
|
|
* we avoid (fail) allocating new blocks during a write.
|
|
*/
|
|
if (ee_len > EXT_MAX_LEN)
|
|
goto out2;
|
|
/* if found extent covers block, simply return it */
|
|
if (iblock >= ee_block && iblock < ee_block + ee_len) {
|
|
newblock = iblock - ee_block + ee_start;
|
|
/* number of remaining blocks in the extent */
|
|
allocated = ee_len - (iblock - ee_block);
|
|
ext_debug("%d fit into %lu:%d -> %llu\n", (int) iblock,
|
|
ee_block, ee_len, newblock);
|
|
ext4_ext_put_in_cache(inode, ee_block, ee_len,
|
|
ee_start, EXT4_EXT_CACHE_EXTENT);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* requested block isn't allocated yet;
|
|
* we couldn't try to create block if create flag is zero
|
|
*/
|
|
if (!create) {
|
|
/* put just found gap into cache to speed up
|
|
* subsequent requests */
|
|
ext4_ext_put_gap_in_cache(inode, path, iblock);
|
|
goto out2;
|
|
}
|
|
/*
|
|
* Okay, we need to do block allocation. Lazily initialize the block
|
|
* allocation info here if necessary.
|
|
*/
|
|
if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info))
|
|
ext4_init_block_alloc_info(inode);
|
|
|
|
/* allocate new block */
|
|
goal = ext4_ext_find_goal(inode, path, iblock);
|
|
allocated = max_blocks;
|
|
newblock = ext4_new_blocks(handle, inode, goal, &allocated, &err);
|
|
if (!newblock)
|
|
goto out2;
|
|
ext_debug("allocate new block: goal %llu, found %llu/%lu\n",
|
|
goal, newblock, allocated);
|
|
|
|
/* try to insert new extent into found leaf and return */
|
|
newex.ee_block = cpu_to_le32(iblock);
|
|
ext4_ext_store_pblock(&newex, newblock);
|
|
newex.ee_len = cpu_to_le16(allocated);
|
|
err = ext4_ext_insert_extent(handle, inode, path, &newex);
|
|
if (err)
|
|
goto out2;
|
|
|
|
if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
|
|
EXT4_I(inode)->i_disksize = inode->i_size;
|
|
|
|
/* previous routine could use block we allocated */
|
|
newblock = ext_pblock(&newex);
|
|
__set_bit(BH_New, &bh_result->b_state);
|
|
|
|
ext4_ext_put_in_cache(inode, iblock, allocated, newblock,
|
|
EXT4_EXT_CACHE_EXTENT);
|
|
out:
|
|
if (allocated > max_blocks)
|
|
allocated = max_blocks;
|
|
ext4_ext_show_leaf(inode, path);
|
|
__set_bit(BH_Mapped, &bh_result->b_state);
|
|
bh_result->b_bdev = inode->i_sb->s_bdev;
|
|
bh_result->b_blocknr = newblock;
|
|
out2:
|
|
if (path) {
|
|
ext4_ext_drop_refs(path);
|
|
kfree(path);
|
|
}
|
|
mutex_unlock(&EXT4_I(inode)->truncate_mutex);
|
|
|
|
return err ? err : allocated;
|
|
}
|
|
|
|
void ext4_ext_truncate(struct inode * inode, struct page *page)
|
|
{
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct super_block *sb = inode->i_sb;
|
|
unsigned long last_block;
|
|
handle_t *handle;
|
|
int err = 0;
|
|
|
|
/*
|
|
* probably first extent we're gonna free will be last in block
|
|
*/
|
|
err = ext4_writepage_trans_blocks(inode) + 3;
|
|
handle = ext4_journal_start(inode, err);
|
|
if (IS_ERR(handle)) {
|
|
if (page) {
|
|
clear_highpage(page);
|
|
flush_dcache_page(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (page)
|
|
ext4_block_truncate_page(handle, page, mapping, inode->i_size);
|
|
|
|
mutex_lock(&EXT4_I(inode)->truncate_mutex);
|
|
ext4_ext_invalidate_cache(inode);
|
|
|
|
/*
|
|
* TODO: optimization is possible here.
|
|
* Probably we need not scan at all,
|
|
* because page truncation is enough.
|
|
*/
|
|
if (ext4_orphan_add(handle, inode))
|
|
goto out_stop;
|
|
|
|
/* we have to know where to truncate from in crash case */
|
|
EXT4_I(inode)->i_disksize = inode->i_size;
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
|
|
last_block = (inode->i_size + sb->s_blocksize - 1)
|
|
>> EXT4_BLOCK_SIZE_BITS(sb);
|
|
err = ext4_ext_remove_space(inode, last_block);
|
|
|
|
/* In a multi-transaction truncate, we only make the final
|
|
* transaction synchronous. */
|
|
if (IS_SYNC(inode))
|
|
handle->h_sync = 1;
|
|
|
|
out_stop:
|
|
/*
|
|
* If this was a simple ftruncate() and the file will remain alive,
|
|
* then we need to clear up the orphan record which we created above.
|
|
* However, if this was a real unlink then we were called by
|
|
* ext4_delete_inode(), and we allow that function to clean up the
|
|
* orphan info for us.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(handle, inode);
|
|
|
|
mutex_unlock(&EXT4_I(inode)->truncate_mutex);
|
|
ext4_journal_stop(handle);
|
|
}
|
|
|
|
/*
|
|
* ext4_ext_writepage_trans_blocks:
|
|
* calculate max number of blocks we could modify
|
|
* in order to allocate new block for an inode
|
|
*/
|
|
int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
|
|
{
|
|
int needed;
|
|
|
|
needed = ext4_ext_calc_credits_for_insert(inode, NULL);
|
|
|
|
/* caller wants to allocate num blocks, but note it includes sb */
|
|
needed = needed * num - (num - 1);
|
|
|
|
#ifdef CONFIG_QUOTA
|
|
needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
|
|
#endif
|
|
|
|
return needed;
|
|
}
|
|
|
|
EXPORT_SYMBOL(ext4_mark_inode_dirty);
|
|
EXPORT_SYMBOL(ext4_ext_invalidate_cache);
|
|
EXPORT_SYMBOL(ext4_ext_insert_extent);
|
|
EXPORT_SYMBOL(ext4_ext_walk_space);
|
|
EXPORT_SYMBOL(ext4_ext_find_goal);
|
|
EXPORT_SYMBOL(ext4_ext_calc_credits_for_insert);
|
|
|