ext4: avoid excessive credit estimate in ext4_tmpfile()
[ Upstream commit 35a1f12f0ca857fee1d7a04ef52cbd5f1f84de13 ]
A user with minimum journal size (1024 blocks these days) complained
about the following error triggered by generic/697 test in
ext4_tmpfile():
run fstests generic/697 at 2024-02-28 05:34:46
JBD2: vfstest wants too many credits credits:260 rsv_credits:0 max:256
EXT4-fs error (device loop0) in __ext4_new_inode:1083: error 28
Indeed the credit estimate in ext4_tmpfile() is huge.
EXT4_MAXQUOTAS_INIT_BLOCKS() is 219, then 10 credits from ext4_tmpfile()
itself and then ext4_xattr_credits_for_new_inode() adds more credits
needed for security attributes and ACLs. Now the
EXT4_MAXQUOTAS_INIT_BLOCKS() is in fact unnecessary because we've
already initialized quotas with dquot_init() shortly before and so
EXT4_MAXQUOTAS_TRANS_BLOCKS() is enough (which boils down to 3 credits).
Fixes: af51a2ac36d1 ("ext4: ->tmpfile() support")
Signed-off-by: Jan Kara <jack@suse.cz>
Tested-by: Luis Henriques <lhenriques@suse.de>
Tested-by: Disha Goel <disgoel@linux.ibm.com>
Link: https://lore.kernel.org/r/20240307115320.28949-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 1f9e32f9ea3454f79d80c8af7fac54843beba7f6)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index a763216..76744b4 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2603,7 +2603,7 @@
inode = ext4_new_inode_start_handle(dir, mode,
NULL, 0, NULL,
EXT4_HT_DIR,
- EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
+ EXT4_MAXQUOTAS_TRANS_BLOCKS(dir->i_sb) +
4 + EXT4_XATTR_TRANS_BLOCKS);
handle = ext4_journal_current_handle();
err = PTR_ERR(inode);