NFSv4: Fix locking in pnfs_generic_recover_commit_reqs

The use of the inode->i_lock was converted to a mutex, but we forgot
to remove the old inode unlock/lock() pair that allowed the layout
segment to be put inside the loop.

Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Fixes: e824f99adaaf1 ("NFSv4: Use a mutex to protect the per-inode commit...")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/pnfs_nfs.c b/fs/nfs/pnfs_nfs.c
index 32ba2d47185303419270acf6891fc28ead9f8e8e..d5e4d3cd8c7f15762ef11de727a2fbcdb10c3f7a 100644 (file)
--- a/fs/nfs/pnfs_nfs.c
+++ b/fs/nfs/pnfs_nfs.c
@@ -61,7 +61,7 @@ EXPORT_SYMBOL_GPL(pnfs_generic_commit_release);
 
 /* The generic layer is about to remove the req from the commit list.
  * If this will make the bucket empty, it will need to put the lseg reference.
- * Note this must be called holding i_lock
+ * Note this must be called holding nfsi->commit_mutex
  */
 void
 pnfs_generic_clear_request_commit(struct nfs_page *req,
@@ -149,9 +149,7 @@ void pnfs_generic_recover_commit_reqs(struct list_head *dst,
                if (list_empty(&b->written)) {
                        freeme = b->wlseg;
                        b->wlseg = NULL;
-                       spin_unlock(&cinfo->inode->i_lock);
                        pnfs_put_lseg(freeme);
-                       spin_lock(&cinfo->inode->i_lock);
                        goto restart;
                }
        }
@@ -167,7 +165,7 @@ static void pnfs_generic_retry_commit(struct nfs_commit_info *cinfo, int idx)
        LIST_HEAD(pages);
        int i;
 
-       spin_lock(&cinfo->inode->i_lock);
+       mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
        for (i = idx; i < fl_cinfo->nbuckets; i++) {
                bucket = &fl_cinfo->buckets[i];
                if (list_empty(&bucket->committing))
@@ -177,12 +175,12 @@ static void pnfs_generic_retry_commit(struct nfs_commit_info *cinfo, int idx)
                list_for_each(pos, &bucket->committing)
                        cinfo->ds->ncommitting--;
                list_splice_init(&bucket->committing, &pages);
-               spin_unlock(&cinfo->inode->i_lock);
+               mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
                nfs_retry_commit(&pages, freeme, cinfo, i);
                pnfs_put_lseg(freeme);
-               spin_lock(&cinfo->inode->i_lock);
+               mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
        }
-       spin_unlock(&cinfo->inode->i_lock);
+       mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
 }
 
 static unsigned int
@@ -222,13 +220,13 @@ void pnfs_fetch_commit_bucket_list(struct list_head *pages,
        struct list_head *pos;
 
        bucket = &cinfo->ds->buckets[data->ds_commit_index];
-       spin_lock(&cinfo->inode->i_lock);
+       mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
        list_for_each(pos, &bucket->committing)
                cinfo->ds->ncommitting--;
        list_splice_init(&bucket->committing, pages);
        data->lseg = bucket->clseg;
        bucket->clseg = NULL;
-       spin_unlock(&cinfo->inode->i_lock);
+       mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
 
 }