ext4: improve journal credit handling in set xattr paths

Both ext4_set_acl() and ext4_set_context() need to be made aware of
ea_inode feature when it comes to credits calculation.

Also add a sufficient credits check in ext4_xattr_set_handle() right
after xattr write lock is grabbed. Original credits calculation is done
outside the lock so there is a possiblity that the initially calculated
credits are not sufficient anymore.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Tahsin Erdogan 2017-06-21 22:28:40 -04:00 committed by Theodore Ts'o
parent 65d3000520
commit c1a5d5f6ab
5 changed files with 51 additions and 32 deletions

View File

@ -231,14 +231,15 @@ int
ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
handle_t *handle;
int error, retries = 0;
int error, credits, retries = 0;
size_t acl_size = acl ? ext4_acl_size(acl->a_count) : 0;
error = dquot_initialize(inode);
if (error)
return error;
retry:
handle = ext4_journal_start(inode, EXT4_HT_XATTR,
ext4_jbd2_credits_xattr(inode));
credits = ext4_xattr_set_credits(inode, acl_size);
handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
if (IS_ERR(handle))
return PTR_ERR(handle);

View File

@ -111,20 +111,6 @@
#define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
#define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))
static inline int ext4_jbd2_credits_xattr(struct inode *inode)
{
int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb);
/*
* In case of inline data, we may push out the data to a block,
* so we need to reserve credits for this eventuality
*/
if (ext4_has_inline_data(inode))
credits += ext4_writepage_trans_blocks(inode) + 1;
return credits;
}
/*
* Ext4 handle operation types -- for logging purposes
*/

View File

@ -1143,7 +1143,7 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
void *fs_data)
{
handle_t *handle = fs_data;
int res, res2, retries = 0;
int res, res2, credits, retries = 0;
res = ext4_convert_inline_data(inode);
if (res)
@ -1178,8 +1178,8 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
if (res)
return res;
retry:
handle = ext4_journal_start(inode, EXT4_HT_MISC,
ext4_jbd2_credits_xattr(inode));
credits = ext4_xattr_set_credits(inode, len);
handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
if (IS_ERR(handle))
return PTR_ERR(handle);

View File

@ -1471,6 +1471,17 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
ext4_write_lock_xattr(inode, &no_expand);
/* Check journal credits under write lock. */
if (ext4_handle_valid(handle)) {
int credits;
credits = ext4_xattr_set_credits(inode, value_len);
if (!ext4_handle_has_enough_credits(handle, credits)) {
error = -ENOSPC;
goto cleanup;
}
}
error = ext4_reserve_inode_write(handle, inode, &is.iloc);
if (error)
goto cleanup;
@ -1568,6 +1579,36 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
return error;
}
int ext4_xattr_set_credits(struct inode *inode, size_t value_len)
{
struct super_block *sb = inode->i_sb;
int credits;
if (!EXT4_SB(sb)->s_journal)
return 0;
credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb);
/*
* In case of inline data, we may push out the data to a block,
* so we need to reserve credits for this eventuality
*/
if (ext4_has_inline_data(inode))
credits += ext4_writepage_trans_blocks(inode) + 1;
if (ext4_has_feature_ea_inode(sb)) {
int nrblocks = (value_len + sb->s_blocksize - 1) >>
sb->s_blocksize_bits;
/* For new inode */
credits += EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + 3;
/* For data blocks of EA inode */
credits += ext4_meta_trans_blocks(inode, nrblocks, 0);
}
return credits;
}
/*
* ext4_xattr_set()
*
@ -1583,24 +1624,14 @@ ext4_xattr_set(struct inode *inode, int name_index, const char *name,
handle_t *handle;
struct super_block *sb = inode->i_sb;
int error, retries = 0;
int credits = ext4_jbd2_credits_xattr(inode);
int credits;
error = dquot_initialize(inode);
if (error)
return error;
if (ext4_has_feature_ea_inode(sb)) {
int nrblocks = (value_len + sb->s_blocksize - 1) >>
sb->s_blocksize_bits;
/* For new inode */
credits += EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + 3;
/* For data blocks of EA inode */
credits += ext4_meta_trans_blocks(inode, nrblocks, 0);
}
retry:
credits = ext4_xattr_set_credits(inode, value_len);
handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits);
if (IS_ERR(handle)) {
error = PTR_ERR(handle);

View File

@ -160,6 +160,7 @@ extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
extern int ext4_xattr_set_credits(struct inode *inode, size_t value_len);
extern int ext4_xattr_inode_unlink(struct inode *inode, unsigned long ea_ino);
extern int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode,