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| author | Amir Goldstein <amir73il@gmail.com> | 2022-04-22 15:03:20 +0300 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2022-04-25 14:37:31 +0200 |
| commit | b8962a9d8cc2d8c93362e2f684091c79f702f6f3 (patch) | |
| tree | 8eb1745ec6e28b8f540dccc63cbb03097bbf2053 | |
| parent | 960bdff24ce802e38df918ebfcbfa62744d6ae22 (diff) | |
| download | linux-next-b8962a9d8cc2d8c93362e2f684091c79f702f6f3.tar.gz | |
nfsd: use fsnotify group lock helpers
Before commit 9542e6a643fc6 ("nfsd: Containerise filecache laundrette")
nfsd would close open files in direct reclaim context and that could
cause a deadlock when fsnotify mark allocation went into direct reclaim
and nfsd shrinker tried to free existing fsnotify marks.
To avoid issues like this in future code, set the FSNOTIFY_GROUP_NOFS
flag on nfsd fsnotify group to prevent going into direct reclaim from
fsnotify_add_inode_mark().
Link: https://lore.kernel.org/r/20220422120327.3459282-10-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
| -rw-r--r-- | fs/nfsd/filecache.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 74ddb828fd75..489c9c1d8f31 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -119,14 +119,14 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf) struct inode *inode = nf->nf_inode; do { - mutex_lock(&nfsd_file_fsnotify_group->mark_mutex); + fsnotify_group_lock(nfsd_file_fsnotify_group); mark = fsnotify_find_mark(&inode->i_fsnotify_marks, - nfsd_file_fsnotify_group); + nfsd_file_fsnotify_group); if (mark) { nfm = nfsd_file_mark_get(container_of(mark, struct nfsd_file_mark, nfm_mark)); - mutex_unlock(&nfsd_file_fsnotify_group->mark_mutex); + fsnotify_group_unlock(nfsd_file_fsnotify_group); if (nfm) { fsnotify_put_mark(mark); break; @@ -134,8 +134,9 @@ nfsd_file_mark_find_or_create(struct nfsd_file *nf) /* Avoid soft lockup race with nfsd_file_mark_put() */ fsnotify_destroy_mark(mark, nfsd_file_fsnotify_group); fsnotify_put_mark(mark); - } else - mutex_unlock(&nfsd_file_fsnotify_group->mark_mutex); + } else { + fsnotify_group_unlock(nfsd_file_fsnotify_group); + } /* allocate a new nfm */ new = kmem_cache_alloc(nfsd_file_mark_slab, GFP_KERNEL); @@ -679,7 +680,7 @@ nfsd_file_cache_init(void) } nfsd_file_fsnotify_group = fsnotify_alloc_group(&nfsd_file_fsnotify_ops, - 0); + FSNOTIFY_GROUP_NOFS); if (IS_ERR(nfsd_file_fsnotify_group)) { pr_err("nfsd: unable to create fsnotify group: %ld\n", PTR_ERR(nfsd_file_fsnotify_group)); |