alistair23-linux/fs/hpfs/inode.c
Johannes Weiner 91b0abe36a mm + fs: store shadow entries in page cache
Reclaim will be leaving shadow entries in the page cache radix tree upon
evicting the real page.  As those pages are found from the LRU, an
iput() can lead to the inode being freed concurrently.  At this point,
reclaim must no longer install shadow pages because the inode freeing
code needs to ensure the page tree is really empty.

Add an address_space flag, AS_EXITING, that the inode freeing code sets
under the tree lock before doing the final truncate.  Reclaim will check
for this flag before installing shadow pages.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Metin Doslu <metin@citusdata.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Ozgun Erdogan <ozgun@citusdata.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:01 -07:00

315 lines
8.8 KiB
C

/*
* linux/fs/hpfs/inode.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* inode VFS functions
*/
#include <linux/slab.h>
#include <linux/user_namespace.h>
#include "hpfs_fn.h"
void hpfs_init_inode(struct inode *i)
{
struct super_block *sb = i->i_sb;
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
i->i_uid = hpfs_sb(sb)->sb_uid;
i->i_gid = hpfs_sb(sb)->sb_gid;
i->i_mode = hpfs_sb(sb)->sb_mode;
i->i_size = -1;
i->i_blocks = -1;
hpfs_inode->i_dno = 0;
hpfs_inode->i_n_secs = 0;
hpfs_inode->i_file_sec = 0;
hpfs_inode->i_disk_sec = 0;
hpfs_inode->i_dpos = 0;
hpfs_inode->i_dsubdno = 0;
hpfs_inode->i_ea_mode = 0;
hpfs_inode->i_ea_uid = 0;
hpfs_inode->i_ea_gid = 0;
hpfs_inode->i_ea_size = 0;
hpfs_inode->i_rddir_off = NULL;
hpfs_inode->i_dirty = 0;
i->i_ctime.tv_sec = i->i_ctime.tv_nsec = 0;
i->i_mtime.tv_sec = i->i_mtime.tv_nsec = 0;
i->i_atime.tv_sec = i->i_atime.tv_nsec = 0;
}
void hpfs_read_inode(struct inode *i)
{
struct buffer_head *bh;
struct fnode *fnode;
struct super_block *sb = i->i_sb;
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
void *ea;
int ea_size;
if (!(fnode = hpfs_map_fnode(sb, i->i_ino, &bh))) {
/*i->i_mode |= S_IFREG;
i->i_mode &= ~0111;
i->i_op = &hpfs_file_iops;
i->i_fop = &hpfs_file_ops;
clear_nlink(i);*/
make_bad_inode(i);
return;
}
if (hpfs_sb(i->i_sb)->sb_eas) {
if ((ea = hpfs_get_ea(i->i_sb, fnode, "UID", &ea_size))) {
if (ea_size == 2) {
i_uid_write(i, le16_to_cpu(*(__le16*)ea));
hpfs_inode->i_ea_uid = 1;
}
kfree(ea);
}
if ((ea = hpfs_get_ea(i->i_sb, fnode, "GID", &ea_size))) {
if (ea_size == 2) {
i_gid_write(i, le16_to_cpu(*(__le16*)ea));
hpfs_inode->i_ea_gid = 1;
}
kfree(ea);
}
if ((ea = hpfs_get_ea(i->i_sb, fnode, "SYMLINK", &ea_size))) {
kfree(ea);
i->i_mode = S_IFLNK | 0777;
i->i_op = &page_symlink_inode_operations;
i->i_data.a_ops = &hpfs_symlink_aops;
set_nlink(i, 1);
i->i_size = ea_size;
i->i_blocks = 1;
brelse(bh);
return;
}
if ((ea = hpfs_get_ea(i->i_sb, fnode, "MODE", &ea_size))) {
int rdev = 0;
umode_t mode = hpfs_sb(sb)->sb_mode;
if (ea_size == 2) {
mode = le16_to_cpu(*(__le16*)ea);
hpfs_inode->i_ea_mode = 1;
}
kfree(ea);
i->i_mode = mode;
if (S_ISBLK(mode) || S_ISCHR(mode)) {
if ((ea = hpfs_get_ea(i->i_sb, fnode, "DEV", &ea_size))) {
if (ea_size == 4)
rdev = le32_to_cpu(*(__le32*)ea);
kfree(ea);
}
}
if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
brelse(bh);
set_nlink(i, 1);
i->i_size = 0;
i->i_blocks = 1;
init_special_inode(i, mode,
new_decode_dev(rdev));
return;
}
}
}
if (fnode_is_dir(fnode)) {
int n_dnodes, n_subdirs;
i->i_mode |= S_IFDIR;
i->i_op = &hpfs_dir_iops;
i->i_fop = &hpfs_dir_ops;
hpfs_inode->i_parent_dir = le32_to_cpu(fnode->up);
hpfs_inode->i_dno = le32_to_cpu(fnode->u.external[0].disk_secno);
if (hpfs_sb(sb)->sb_chk >= 2) {
struct buffer_head *bh0;
if (hpfs_map_fnode(sb, hpfs_inode->i_parent_dir, &bh0)) brelse(bh0);
}
n_dnodes = 0; n_subdirs = 0;
hpfs_count_dnodes(i->i_sb, hpfs_inode->i_dno, &n_dnodes, &n_subdirs, NULL);
i->i_blocks = 4 * n_dnodes;
i->i_size = 2048 * n_dnodes;
set_nlink(i, 2 + n_subdirs);
} else {
i->i_mode |= S_IFREG;
if (!hpfs_inode->i_ea_mode) i->i_mode &= ~0111;
i->i_op = &hpfs_file_iops;
i->i_fop = &hpfs_file_ops;
set_nlink(i, 1);
i->i_size = le32_to_cpu(fnode->file_size);
i->i_blocks = ((i->i_size + 511) >> 9) + 1;
i->i_data.a_ops = &hpfs_aops;
hpfs_i(i)->mmu_private = i->i_size;
}
brelse(bh);
}
static void hpfs_write_inode_ea(struct inode *i, struct fnode *fnode)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
/*if (le32_to_cpu(fnode->acl_size_l) || le16_to_cpu(fnode->acl_size_s)) {
Some unknown structures like ACL may be in fnode,
we'd better not overwrite them
hpfs_error(i->i_sb, "fnode %08x has some unknown HPFS386 structures", i->i_ino);
} else*/ if (hpfs_sb(i->i_sb)->sb_eas >= 2) {
__le32 ea;
if (!uid_eq(i->i_uid, hpfs_sb(i->i_sb)->sb_uid) || hpfs_inode->i_ea_uid) {
ea = cpu_to_le32(i_uid_read(i));
hpfs_set_ea(i, fnode, "UID", (char*)&ea, 2);
hpfs_inode->i_ea_uid = 1;
}
if (!gid_eq(i->i_gid, hpfs_sb(i->i_sb)->sb_gid) || hpfs_inode->i_ea_gid) {
ea = cpu_to_le32(i_gid_read(i));
hpfs_set_ea(i, fnode, "GID", (char *)&ea, 2);
hpfs_inode->i_ea_gid = 1;
}
if (!S_ISLNK(i->i_mode))
if ((i->i_mode != ((hpfs_sb(i->i_sb)->sb_mode & ~(S_ISDIR(i->i_mode) ? 0 : 0111))
| (S_ISDIR(i->i_mode) ? S_IFDIR : S_IFREG))
&& i->i_mode != ((hpfs_sb(i->i_sb)->sb_mode & ~(S_ISDIR(i->i_mode) ? 0222 : 0333))
| (S_ISDIR(i->i_mode) ? S_IFDIR : S_IFREG))) || hpfs_inode->i_ea_mode) {
ea = cpu_to_le32(i->i_mode);
/* sick, but legal */
hpfs_set_ea(i, fnode, "MODE", (char *)&ea, 2);
hpfs_inode->i_ea_mode = 1;
}
if (S_ISBLK(i->i_mode) || S_ISCHR(i->i_mode)) {
ea = cpu_to_le32(new_encode_dev(i->i_rdev));
hpfs_set_ea(i, fnode, "DEV", (char *)&ea, 4);
}
}
}
void hpfs_write_inode(struct inode *i)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
struct inode *parent;
if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
if (hpfs_inode->i_rddir_off && !atomic_read(&i->i_count)) {
if (*hpfs_inode->i_rddir_off) printk("HPFS: write_inode: some position still there\n");
kfree(hpfs_inode->i_rddir_off);
hpfs_inode->i_rddir_off = NULL;
}
if (!i->i_nlink) {
return;
}
parent = iget_locked(i->i_sb, hpfs_inode->i_parent_dir);
if (parent) {
hpfs_inode->i_dirty = 0;
if (parent->i_state & I_NEW) {
hpfs_init_inode(parent);
hpfs_read_inode(parent);
unlock_new_inode(parent);
}
hpfs_write_inode_nolock(i);
iput(parent);
}
}
void hpfs_write_inode_nolock(struct inode *i)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
struct buffer_head *bh;
struct fnode *fnode;
struct quad_buffer_head qbh;
struct hpfs_dirent *de;
if (i->i_ino == hpfs_sb(i->i_sb)->sb_root) return;
if (!(fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) return;
if (i->i_ino != hpfs_sb(i->i_sb)->sb_root && i->i_nlink) {
if (!(de = map_fnode_dirent(i->i_sb, i->i_ino, fnode, &qbh))) {
brelse(bh);
return;
}
} else de = NULL;
if (S_ISREG(i->i_mode)) {
fnode->file_size = cpu_to_le32(i->i_size);
if (de) de->file_size = cpu_to_le32(i->i_size);
} else if (S_ISDIR(i->i_mode)) {
fnode->file_size = cpu_to_le32(0);
if (de) de->file_size = cpu_to_le32(0);
}
hpfs_write_inode_ea(i, fnode);
if (de) {
de->write_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_mtime.tv_sec));
de->read_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_atime.tv_sec));
de->creation_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_ctime.tv_sec));
de->read_only = !(i->i_mode & 0222);
de->ea_size = cpu_to_le32(hpfs_inode->i_ea_size);
hpfs_mark_4buffers_dirty(&qbh);
hpfs_brelse4(&qbh);
}
if (S_ISDIR(i->i_mode)) {
if ((de = map_dirent(i, hpfs_inode->i_dno, "\001\001", 2, NULL, &qbh))) {
de->write_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_mtime.tv_sec));
de->read_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_atime.tv_sec));
de->creation_date = cpu_to_le32(gmt_to_local(i->i_sb, i->i_ctime.tv_sec));
de->read_only = !(i->i_mode & 0222);
de->ea_size = cpu_to_le32(/*hpfs_inode->i_ea_size*/0);
de->file_size = cpu_to_le32(0);
hpfs_mark_4buffers_dirty(&qbh);
hpfs_brelse4(&qbh);
} else
hpfs_error(i->i_sb,
"directory %08lx doesn't have '.' entry",
(unsigned long)i->i_ino);
}
mark_buffer_dirty(bh);
brelse(bh);
}
int hpfs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
int error = -EINVAL;
hpfs_lock(inode->i_sb);
if (inode->i_ino == hpfs_sb(inode->i_sb)->sb_root)
goto out_unlock;
if ((attr->ia_valid & ATTR_UID) &&
from_kuid(&init_user_ns, attr->ia_uid) >= 0x10000)
goto out_unlock;
if ((attr->ia_valid & ATTR_GID) &&
from_kgid(&init_user_ns, attr->ia_gid) >= 0x10000)
goto out_unlock;
if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > inode->i_size)
goto out_unlock;
error = inode_change_ok(inode, attr);
if (error)
goto out_unlock;
if ((attr->ia_valid & ATTR_SIZE) &&
attr->ia_size != i_size_read(inode)) {
error = inode_newsize_ok(inode, attr->ia_size);
if (error)
goto out_unlock;
truncate_setsize(inode, attr->ia_size);
hpfs_truncate(inode);
}
setattr_copy(inode, attr);
hpfs_write_inode(inode);
out_unlock:
hpfs_unlock(inode->i_sb);
return error;
}
void hpfs_write_if_changed(struct inode *inode)
{
struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
if (hpfs_inode->i_dirty)
hpfs_write_inode(inode);
}
void hpfs_evict_inode(struct inode *inode)
{
truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
if (!inode->i_nlink) {
hpfs_lock(inode->i_sb);
hpfs_remove_fnode(inode->i_sb, inode->i_ino);
hpfs_unlock(inode->i_sb);
}
}