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Revert "nfs: don't reuse partially completed requests in nfs_lock_and_join_requests"

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This reverts commit b571cfcb9d.

This patch appears to assume that if one request is complete, then the
others will complete too before unlocking. That is not a valid
assumption, since other requests could hit a non-fatal error or a short
write that would cause them not to complete.

Reported-by: Igor Raits <igor@gooddata.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219508
Fixes: b571cfcb9d ("nfs: don't reuse partially completed requests in nfs_lock_and_join_requests")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Trond Myklebust 2024-11-04 21:09:21 -05:00
parent 8f52caf9d2
commit 66f9dac907
1 changed files with 29 additions and 20 deletions
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49
fs/nfs/write.c
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@ -144,6 +144,31 @@ static void nfs_io_completion_put(struct nfs_io_completion *ioc)
kref_put(&ioc->refcount, nfs_io_completion_release); kref_put(&ioc->refcount, nfs_io_completion_release);
} }
static void
nfs_page_set_inode_ref(struct nfs_page *req, struct inode *inode)
{
if (!test_and_set_bit(PG_INODE_REF, &req->wb_flags)) {
kref_get(&req->wb_kref);
atomic_long_inc(&NFS_I(inode)->nrequests);
}
}
static int
nfs_cancel_remove_inode(struct nfs_page *req, struct inode *inode)
{
int ret;
if (!test_bit(PG_REMOVE, &req->wb_flags))
return 0;
ret = nfs_page_group_lock(req);
if (ret)
return ret;
if (test_and_clear_bit(PG_REMOVE, &req->wb_flags))
nfs_page_set_inode_ref(req, inode);
nfs_page_group_unlock(req);
return 0;
}
/** /**
* nfs_folio_find_head_request - find head request associated with a folio * nfs_folio_find_head_request - find head request associated with a folio
* @folio: pointer to folio * @folio: pointer to folio
@ -540,7 +565,6 @@ static struct nfs_page *nfs_lock_and_join_requests(struct folio *folio)
struct inode *inode = folio->mapping->host; struct inode *inode = folio->mapping->host;
struct nfs_page *head, *subreq; struct nfs_page *head, *subreq;
struct nfs_commit_info cinfo; struct nfs_commit_info cinfo;
bool removed;
int ret; int ret;
/* /*
@ -565,18 +589,18 @@ static struct nfs_page *nfs_lock_and_join_requests(struct folio *folio)
goto retry; goto retry;
} }
ret = nfs_page_group_lock(head); ret = nfs_cancel_remove_inode(head, inode);
if (ret < 0) if (ret < 0)
goto out_unlock; goto out_unlock;
removed = test_bit(PG_REMOVE, &head->wb_flags); ret = nfs_page_group_lock(head);
if (ret < 0)
goto out_unlock;
/* lock each request in the page group */ /* lock each request in the page group */
for (subreq = head->wb_this_page; for (subreq = head->wb_this_page;
subreq != head; subreq != head;
subreq = subreq->wb_this_page) { subreq = subreq->wb_this_page) {
if (test_bit(PG_REMOVE, &subreq->wb_flags))
removed = true;
ret = nfs_page_group_lock_subreq(head, subreq); ret = nfs_page_group_lock_subreq(head, subreq);
if (ret < 0) if (ret < 0)
goto out_unlock; goto out_unlock;
@ -584,21 +608,6 @@ static struct nfs_page *nfs_lock_and_join_requests(struct folio *folio)
nfs_page_group_unlock(head); nfs_page_group_unlock(head);
/*
* If PG_REMOVE is set on any request, I/O on that request has
* completed, but some requests were still under I/O at the time
* we locked the head request.
*
* In that case the above wait for all requests means that all I/O
* has now finished, and we can restart from a clean slate. Let the
* old requests go away and start from scratch instead.
*/
if (removed) {
nfs_unroll_locks(head, head);
nfs_unlock_and_release_request(head);
goto retry;
}
nfs_init_cinfo_from_inode(&cinfo, inode); nfs_init_cinfo_from_inode(&cinfo, inode);
nfs_join_page_group(head, &cinfo, inode); nfs_join_page_group(head, &cinfo, inode);
return head; return head;