From 834224e81cdc265456f73fed748a349e43e2d8ef Mon Sep 17 00:00:00 2001 From: Harshad Shirwadkar Date: Thu, 8 May 2025 17:59:00 +0000 Subject: [PATCH] ext4: convert i_fc_lock to spinlock Convert ext4_inode_info->i_fc_lock to spinlock to avoid sleeping in invalid contexts. Reviewed-by: Jan Kara Signed-off-by: Harshad Shirwadkar Link: https://patch.msgid.link/20250508175908.1004880-2-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o --- fs/ext4/ext4.h | 7 +++++-- fs/ext4/fast_commit.c | 19 +++++++++---------- fs/ext4/super.c | 2 +- 3 files changed, 15 insertions(+), 13 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 5a20e9cd7184..79dfb57a7046 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1069,8 +1069,11 @@ struct ext4_inode_info { /* Fast commit wait queue for this inode */ wait_queue_head_t i_fc_wait; - /* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */ - struct mutex i_fc_lock; + /* + * Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len + * and inode's EXT4_FC_STATE_COMMITTING state bit. + */ + spinlock_t i_fc_lock; /* * i_disksize keeps track of what the inode size is ON DISK, not diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index da4263a14a20..63859ec6d91d 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -385,7 +385,7 @@ static int ext4_fc_track_template( int ret; tid = handle->h_transaction->t_tid; - mutex_lock(&ei->i_fc_lock); + spin_lock(&ei->i_fc_lock); if (tid == ei->i_sync_tid) { update = true; } else { @@ -393,8 +393,7 @@ static int ext4_fc_track_template( ei->i_sync_tid = tid; } ret = __fc_track_fn(handle, inode, args, update); - mutex_unlock(&ei->i_fc_lock); - + spin_unlock(&ei->i_fc_lock); if (!enqueue) return ret; @@ -428,19 +427,19 @@ static int __track_dentry_update(handle_t *handle, struct inode *inode, struct super_block *sb = inode->i_sb; struct ext4_sb_info *sbi = EXT4_SB(sb); - mutex_unlock(&ei->i_fc_lock); + spin_unlock(&ei->i_fc_lock); if (IS_ENCRYPTED(dir)) { ext4_fc_mark_ineligible(sb, EXT4_FC_REASON_ENCRYPTED_FILENAME, handle); - mutex_lock(&ei->i_fc_lock); + spin_lock(&ei->i_fc_lock); return -EOPNOTSUPP; } node = kmem_cache_alloc(ext4_fc_dentry_cachep, GFP_NOFS); if (!node) { ext4_fc_mark_ineligible(sb, EXT4_FC_REASON_NOMEM, handle); - mutex_lock(&ei->i_fc_lock); + spin_lock(&ei->i_fc_lock); return -ENOMEM; } @@ -471,7 +470,7 @@ static int __track_dentry_update(handle_t *handle, struct inode *inode, list_add_tail(&node->fcd_dilist, &ei->i_fc_dilist); } spin_unlock(&sbi->s_fc_lock); - mutex_lock(&ei->i_fc_lock); + spin_lock(&ei->i_fc_lock); return 0; } @@ -893,15 +892,15 @@ static int ext4_fc_write_inode_data(struct inode *inode, u32 *crc) struct ext4_extent *ex; int ret; - mutex_lock(&ei->i_fc_lock); + spin_lock(&ei->i_fc_lock); if (ei->i_fc_lblk_len == 0) { - mutex_unlock(&ei->i_fc_lock); + spin_unlock(&ei->i_fc_lock); return 0; } old_blk_size = ei->i_fc_lblk_start; new_blk_size = ei->i_fc_lblk_start + ei->i_fc_lblk_len - 1; ei->i_fc_lblk_len = 0; - mutex_unlock(&ei->i_fc_lock); + spin_unlock(&ei->i_fc_lock); cur_lblk_off = old_blk_size; ext4_debug("will try writing %d to %d for inode %ld\n", diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 181934499624..ed8166fe2ad0 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1415,7 +1415,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) ei->i_datasync_tid = 0; INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work); ext4_fc_init_inode(&ei->vfs_inode); - mutex_init(&ei->i_fc_lock); + spin_lock_init(&ei->i_fc_lock); return &ei->vfs_inode; } -- 2.25.1