From daf647d2dd58cec59570d7698a45b98e580f2076 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Fri, 1 Apr 2016 01:31:28 -0400 Subject: ext4: add lockdep annotations for i_data_sem With the internal Quota feature, mke2fs creates empty quota inodes and quota usage tracking is enabled as soon as the file system is mounted. Since quotacheck is no longer preallocating all of the blocks in the quota inode that are likely needed to be written to, we are now seeing a lockdep false positive caused by needing to allocate a quota block from inside ext4_map_blocks(), while holding i_data_sem for a data inode. This results in this complaint: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem); lock(&s->s_dquot.dqio_mutex); lock(&ei->i_data_sem); lock(&s->s_dquot.dqio_mutex); Google-Bug-Id: 27907753 Signed-off-by: Theodore Ts'o Cc: stable@vger.kernel.org --- fs/ext4/super.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 539297515896..7ebd9f040b16 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5028,6 +5028,20 @@ static int ext4_quota_on_mount(struct super_block *sb, int type) EXT4_SB(sb)->s_jquota_fmt, type); } +static void lockdep_set_quota_inode(struct inode *inode, int subclass) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + + /* The first argument of lockdep_set_subclass has to be + * *exactly* the same as the argument to init_rwsem() --- in + * this case, in init_once() --- or lockdep gets unhappy + * because the name of the lock is set using the + * stringification of the argument to init_rwsem(). + */ + (void) ei; /* shut up clang warning if !CONFIG_LOCKDEP */ + lockdep_set_subclass(&ei->i_data_sem, subclass); +} + /* * Standard function to be called on quota_on */ @@ -5067,8 +5081,12 @@ static int ext4_quota_on(struct super_block *sb, int type, int format_id, if (err) return err; } - - return dquot_quota_on(sb, type, format_id, path); + lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA); + err = dquot_quota_on(sb, type, format_id, path); + if (err) + lockdep_set_quota_inode(path->dentry->d_inode, + I_DATA_SEM_NORMAL); + return err; } static int ext4_quota_enable(struct super_block *sb, int type, int format_id, @@ -5095,8 +5113,11 @@ static int ext4_quota_enable(struct super_block *sb, int type, int format_id, /* Don't account quota for quota files to avoid recursion */ qf_inode->i_flags |= S_NOQUOTA; + lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA); err = dquot_enable(qf_inode, type, format_id, flags); iput(qf_inode); + if (err) + lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL); return err; } -- cgit v1.2.3 From 8f0e8746b4d57303d84f7b161a201e94fe22638f Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Fri, 1 Apr 2016 12:00:03 -0400 Subject: ext4: avoid calling dquot_get_next_id() if quota is not enabled This should be fixed in the quota layer so we can test with the quota mutex held, but for now, we need this to avoid tests from crashing the kernel aborting the regression test suite. Signed-off-by: Theodore Ts'o --- fs/ext4/super.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 7ebd9f040b16..51a131162c11 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1113,6 +1113,7 @@ static ssize_t ext4_quota_write(struct super_block *sb, int type, static int ext4_quota_enable(struct super_block *sb, int type, int format_id, unsigned int flags); static int ext4_enable_quotas(struct super_block *sb); +static int ext4_get_next_id(struct super_block *sb, struct kqid *qid); static struct dquot **ext4_get_dquots(struct inode *inode) { @@ -1129,7 +1130,7 @@ static const struct dquot_operations ext4_quota_operations = { .alloc_dquot = dquot_alloc, .destroy_dquot = dquot_destroy, .get_projid = ext4_get_projid, - .get_next_id = dquot_get_next_id, + .get_next_id = ext4_get_next_id, }; static const struct quotactl_ops ext4_qctl_operations = { @@ -5274,6 +5275,17 @@ out: return len; } +static int ext4_get_next_id(struct super_block *sb, struct kqid *qid) +{ + const struct quota_format_ops *ops; + + if (!sb_has_quota_loaded(sb, qid->type)) + return -ESRCH; + ops = sb_dqopt(sb)->ops[qid->type]; + if (!ops || !ops->get_next_id) + return -ENOSYS; + return dquot_get_next_id(sb, qid); +} #endif static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags, -- cgit v1.2.3 From c325a67c72903e1cc30e990a15ce745bda0dbfde Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sun, 3 Apr 2016 17:03:37 -0400 Subject: ext4: ignore quota mount options if the quota feature is enabled Previously, ext4 would fail the mount if the file system had the quota feature enabled and quota mount options (used for the older quota setups) were present. This broke xfstests, since xfs silently ignores the usrquote and grpquota mount options if they are specified. This commit changes things so that we are consistent with xfs; having the mount options specified is harmless, so no sense break users by forbidding them. Cc: stable@vger.kernel.org Signed-off-by: Theodore Ts'o --- fs/ext4/super.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 51a131162c11..df213616dc39 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1324,9 +1324,9 @@ static int set_qf_name(struct super_block *sb, int qtype, substring_t *args) return -1; } if (ext4_has_feature_quota(sb)) { - ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options " - "when QUOTA feature is enabled"); - return -1; + ext4_msg(sb, KERN_INFO, "Journaled quota options " + "ignored when QUOTA feature is enabled"); + return 1; } qname = match_strdup(args); if (!qname) { @@ -1689,10 +1689,10 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, return -1; } if (ext4_has_feature_quota(sb)) { - ext4_msg(sb, KERN_ERR, - "Cannot set journaled quota options " + ext4_msg(sb, KERN_INFO, + "Quota format mount options ignored " "when QUOTA feature is enabled"); - return -1; + return 1; } sbi->s_jquota_fmt = m->mount_opt; #endif @@ -1757,11 +1757,11 @@ static int parse_options(char *options, struct super_block *sb, #ifdef CONFIG_QUOTA if (ext4_has_feature_quota(sb) && (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) { - ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA " - "feature is enabled"); - return 0; - } - if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) { + ext4_msg(sb, KERN_INFO, "Quota feature enabled, usrquota and grpquota " + "mount options ignored."); + clear_opt(sb, USRQUOTA); + clear_opt(sb, GRPQUOTA); + } else if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) { if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA]) clear_opt(sb, USRQUOTA); -- cgit v1.2.3