diff options
author | Ritesh Harjani <riteshh@linux.ibm.com> | 2020-03-28 01:37:44 +0530 |
---|---|---|
committer | Theodore Ts'o <tytso@mit.edu> | 2020-03-28 23:11:04 -0400 |
commit | 626b035b816b61a7a7b4d2205a6807e2f11a18c1 (patch) | |
tree | f6fbae6c313068edf8a237d851efc1d0e3aa7305 | |
parent | c8980e1980ccdc2229aa2218d532ddc62e0aabe5 (diff) |
ext4: don't set dioread_nolock by default for blocksize < pagesize
Currently on calling echo 3 > drop_caches on host machine, we see
FS corruption in the guest. This happens on Power machine where
blocksize < pagesize.
So as a temporary workaound don't enable dioread_nolock by default
for blocksize < pagesize until we identify the root cause.
Also emit a warning msg in case if this mount option is manually
enabled for blocksize < pagesize.
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200327200744.12473-1-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
-rw-r--r-- | fs/ext4/super.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 4d460747cca7..c5639c0ba2c5 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2187,6 +2187,14 @@ static int parse_options(char *options, struct super_block *sb, } } #endif + if (test_opt(sb, DIOREAD_NOLOCK)) { + int blocksize = + BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); + if (blocksize < PAGE_SIZE) + ext4_msg(sb, KERN_WARNING, "Warning: mounting with an " + "experimental mount option 'dioread_nolock' " + "for blocksize < PAGE_SIZE"); + } return 1; } @@ -3793,7 +3801,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) set_opt(sb, NO_UID32); /* xattr user namespace & acls are now defaulted on */ set_opt(sb, XATTR_USER); - set_opt(sb, DIOREAD_NOLOCK); #ifdef CONFIG_EXT4_FS_POSIX_ACL set_opt(sb, POSIX_ACL); #endif @@ -3843,6 +3850,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT; blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size); + + if (blocksize == PAGE_SIZE) + set_opt(sb, DIOREAD_NOLOCK); + if (blocksize < EXT4_MIN_BLOCK_SIZE || blocksize > EXT4_MAX_BLOCK_SIZE) { ext4_msg(sb, KERN_ERR, |