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Diffstat (limited to 'fs/nfs/write.c')
-rw-r--r--fs/nfs/write.c457
1 files changed, 220 insertions, 237 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index b1af5dee5e0a..f68083db63c8 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -102,10 +102,8 @@ static struct nfs_pgio_header *nfs_writehdr_alloc(void)
{
struct nfs_pgio_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO);
- if (p) {
- memset(p, 0, sizeof(*p));
- p->rw_mode = FMODE_WRITE;
- }
+ memset(p, 0, sizeof(*p));
+ p->rw_mode = FMODE_WRITE;
return p;
}
@@ -154,6 +152,14 @@ static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
}
+static struct nfs_page *
+nfs_page_private_request(struct page *page)
+{
+ if (!PagePrivate(page))
+ return NULL;
+ return (struct nfs_page *)page_private(page);
+}
+
/*
* nfs_page_find_head_request_locked - find head request associated with @page
*
@@ -162,21 +168,41 @@ static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
* returns matching head request with reference held, or NULL if not found.
*/
static struct nfs_page *
-nfs_page_find_head_request_locked(struct nfs_inode *nfsi, struct page *page)
+nfs_page_find_private_request(struct page *page)
{
- struct nfs_page *req = NULL;
-
- if (PagePrivate(page))
- req = (struct nfs_page *)page_private(page);
- else if (unlikely(PageSwapCache(page)))
- req = nfs_page_search_commits_for_head_request_locked(nfsi,
- page);
+ struct address_space *mapping = page_file_mapping(page);
+ struct nfs_page *req;
+ if (!PagePrivate(page))
+ return NULL;
+ spin_lock(&mapping->private_lock);
+ req = nfs_page_private_request(page);
if (req) {
WARN_ON_ONCE(req->wb_head != req);
kref_get(&req->wb_kref);
}
+ spin_unlock(&mapping->private_lock);
+ return req;
+}
+static struct nfs_page *
+nfs_page_find_swap_request(struct page *page)
+{
+ struct inode *inode = page_file_mapping(page)->host;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_page *req = NULL;
+ if (!PageSwapCache(page))
+ return NULL;
+ mutex_lock(&nfsi->commit_mutex);
+ if (PageSwapCache(page)) {
+ req = nfs_page_search_commits_for_head_request_locked(nfsi,
+ page);
+ if (req) {
+ WARN_ON_ONCE(req->wb_head != req);
+ kref_get(&req->wb_kref);
+ }
+ }
+ mutex_unlock(&nfsi->commit_mutex);
return req;
}
@@ -187,12 +213,11 @@ nfs_page_find_head_request_locked(struct nfs_inode *nfsi, struct page *page)
*/
static struct nfs_page *nfs_page_find_head_request(struct page *page)
{
- struct inode *inode = page_file_mapping(page)->host;
- struct nfs_page *req = NULL;
+ struct nfs_page *req;
- spin_lock(&inode->i_lock);
- req = nfs_page_find_head_request_locked(NFS_I(inode), page);
- spin_unlock(&inode->i_lock);
+ req = nfs_page_find_private_request(page);
+ if (!req)
+ req = nfs_page_find_swap_request(page);
return req;
}
@@ -241,9 +266,6 @@ nfs_page_group_search_locked(struct nfs_page *head, unsigned int page_offset)
{
struct nfs_page *req;
- WARN_ON_ONCE(head != head->wb_head);
- WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &head->wb_head->wb_flags));
-
req = head;
do {
if (page_offset >= req->wb_pgbase &&
@@ -269,20 +291,17 @@ static bool nfs_page_group_covers_page(struct nfs_page *req)
unsigned int pos = 0;
unsigned int len = nfs_page_length(req->wb_page);
- nfs_page_group_lock(req, false);
+ nfs_page_group_lock(req);
- do {
+ for (;;) {
tmp = nfs_page_group_search_locked(req->wb_head, pos);
- if (tmp) {
- /* no way this should happen */
- WARN_ON_ONCE(tmp->wb_pgbase != pos);
- pos += tmp->wb_bytes - (pos - tmp->wb_pgbase);
- }
- } while (tmp && pos < len);
+ if (!tmp)
+ break;
+ pos = tmp->wb_pgbase + tmp->wb_bytes;
+ }
nfs_page_group_unlock(req);
- WARN_ON_ONCE(pos > len);
- return pos == len;
+ return pos >= len;
}
/* We can set the PG_uptodate flag if we see that a write request
@@ -333,8 +352,11 @@ static void nfs_end_page_writeback(struct nfs_page *req)
{
struct inode *inode = page_file_mapping(req->wb_page)->host;
struct nfs_server *nfss = NFS_SERVER(inode);
+ bool is_done;
- if (!nfs_page_group_sync_on_bit(req, PG_WB_END))
+ is_done = nfs_page_group_sync_on_bit(req, PG_WB_END);
+ nfs_unlock_request(req);
+ if (!is_done)
return;
end_page_writeback(req->wb_page);
@@ -342,22 +364,6 @@ static void nfs_end_page_writeback(struct nfs_page *req)
clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC);
}
-
-/* nfs_page_group_clear_bits
- * @req - an nfs request
- * clears all page group related bits from @req
- */
-static void
-nfs_page_group_clear_bits(struct nfs_page *req)
-{
- clear_bit(PG_TEARDOWN, &req->wb_flags);
- clear_bit(PG_UNLOCKPAGE, &req->wb_flags);
- clear_bit(PG_UPTODATE, &req->wb_flags);
- clear_bit(PG_WB_END, &req->wb_flags);
- clear_bit(PG_REMOVE, &req->wb_flags);
-}
-
-
/*
* nfs_unroll_locks_and_wait - unlock all newly locked reqs and wait on @req
*
@@ -366,43 +372,24 @@ nfs_page_group_clear_bits(struct nfs_page *req)
* @inode - inode associated with request page group, must be holding inode lock
* @head - head request of page group, must be holding head lock
* @req - request that couldn't lock and needs to wait on the req bit lock
- * @nonblock - if true, don't actually wait
*
- * NOTE: this must be called holding page_group bit lock and inode spin lock
- * and BOTH will be released before returning.
+ * NOTE: this must be called holding page_group bit lock
+ * which will be released before returning.
*
* returns 0 on success, < 0 on error.
*/
-static int
-nfs_unroll_locks_and_wait(struct inode *inode, struct nfs_page *head,
- struct nfs_page *req, bool nonblock)
- __releases(&inode->i_lock)
+static void
+nfs_unroll_locks(struct inode *inode, struct nfs_page *head,
+ struct nfs_page *req)
{
struct nfs_page *tmp;
- int ret;
/* relinquish all the locks successfully grabbed this run */
- for (tmp = head ; tmp != req; tmp = tmp->wb_this_page)
- nfs_unlock_request(tmp);
-
- WARN_ON_ONCE(test_bit(PG_TEARDOWN, &req->wb_flags));
-
- /* grab a ref on the request that will be waited on */
- kref_get(&req->wb_kref);
-
- nfs_page_group_unlock(head);
- spin_unlock(&inode->i_lock);
-
- /* release ref from nfs_page_find_head_request_locked */
- nfs_release_request(head);
-
- if (!nonblock)
- ret = nfs_wait_on_request(req);
- else
- ret = -EAGAIN;
- nfs_release_request(req);
-
- return ret;
+ for (tmp = head->wb_this_page ; tmp != req; tmp = tmp->wb_this_page) {
+ if (!kref_read(&tmp->wb_kref))
+ continue;
+ nfs_unlock_and_release_request(tmp);
+ }
}
/*
@@ -417,7 +404,8 @@ nfs_unroll_locks_and_wait(struct inode *inode, struct nfs_page *head,
*/
static void
nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list,
- struct nfs_page *old_head)
+ struct nfs_page *old_head,
+ struct inode *inode)
{
while (destroy_list) {
struct nfs_page *subreq = destroy_list;
@@ -428,33 +416,28 @@ nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list,
WARN_ON_ONCE(old_head != subreq->wb_head);
/* make sure old group is not used */
- subreq->wb_head = subreq;
subreq->wb_this_page = subreq;
- /* subreq is now totally disconnected from page group or any
- * write / commit lists. last chance to wake any waiters */
- nfs_unlock_request(subreq);
+ clear_bit(PG_REMOVE, &subreq->wb_flags);
- if (!test_bit(PG_TEARDOWN, &subreq->wb_flags)) {
- /* release ref on old head request */
- nfs_release_request(old_head);
+ /* Note: races with nfs_page_group_destroy() */
+ if (!kref_read(&subreq->wb_kref)) {
+ /* Check if we raced with nfs_page_group_destroy() */
+ if (test_and_clear_bit(PG_TEARDOWN, &subreq->wb_flags))
+ nfs_free_request(subreq);
+ continue;
+ }
- nfs_page_group_clear_bits(subreq);
+ subreq->wb_head = subreq;
- /* release the PG_INODE_REF reference */
- if (test_and_clear_bit(PG_INODE_REF, &subreq->wb_flags))
- nfs_release_request(subreq);
- else
- WARN_ON_ONCE(1);
- } else {
- WARN_ON_ONCE(test_bit(PG_CLEAN, &subreq->wb_flags));
- /* zombie requests have already released the last
- * reference and were waiting on the rest of the
- * group to complete. Since it's no longer part of a
- * group, simply free the request */
- nfs_page_group_clear_bits(subreq);
- nfs_free_request(subreq);
+ if (test_and_clear_bit(PG_INODE_REF, &subreq->wb_flags)) {
+ nfs_release_request(subreq);
+ atomic_long_dec(&NFS_I(inode)->nrequests);
}
+
+ /* subreq is now totally disconnected from page group or any
+ * write / commit lists. last chance to wake any waiters */
+ nfs_unlock_and_release_request(subreq);
}
}
@@ -464,7 +447,6 @@ nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list,
* operations for this page.
*
* @page - the page used to lookup the "page group" of nfs_page structures
- * @nonblock - if true, don't block waiting for request locks
*
* This function joins all sub requests to the head request by first
* locking all requests in the group, cancelling any pending operations
@@ -478,7 +460,7 @@ nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list,
* error was encountered.
*/
static struct nfs_page *
-nfs_lock_and_join_requests(struct page *page, bool nonblock)
+nfs_lock_and_join_requests(struct page *page)
{
struct inode *inode = page_file_mapping(page)->host;
struct nfs_page *head, *subreq;
@@ -487,43 +469,63 @@ nfs_lock_and_join_requests(struct page *page, bool nonblock)
int ret;
try_again:
- total_bytes = 0;
-
- WARN_ON_ONCE(destroy_list);
-
- spin_lock(&inode->i_lock);
-
/*
* A reference is taken only on the head request which acts as a
* reference to the whole page group - the group will not be destroyed
* until the head reference is released.
*/
- head = nfs_page_find_head_request_locked(NFS_I(inode), page);
-
- if (!head) {
- spin_unlock(&inode->i_lock);
+ head = nfs_page_find_head_request(page);
+ if (!head)
return NULL;
- }
- /* holding inode lock, so always make a non-blocking call to try the
- * page group lock */
- ret = nfs_page_group_lock(head, true);
- if (ret < 0) {
- spin_unlock(&inode->i_lock);
+ /* lock the page head first in order to avoid an ABBA inefficiency */
+ if (!nfs_lock_request(head)) {
+ ret = nfs_wait_on_request(head);
+ nfs_release_request(head);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ goto try_again;
+ }
- if (!nonblock && ret == -EAGAIN) {
- nfs_page_group_lock_wait(head);
- nfs_release_request(head);
- goto try_again;
- }
+ /* Ensure that nobody removed the request before we locked it */
+ if (head != nfs_page_private_request(page) && !PageSwapCache(page)) {
+ nfs_unlock_and_release_request(head);
+ goto try_again;
+ }
- nfs_release_request(head);
+ ret = nfs_page_group_lock(head);
+ if (ret < 0) {
+ nfs_unlock_and_release_request(head);
return ERR_PTR(ret);
}
/* lock each request in the page group */
- subreq = head;
- do {
+ total_bytes = head->wb_bytes;
+ for (subreq = head->wb_this_page; subreq != head;
+ subreq = subreq->wb_this_page) {
+
+ if (!kref_get_unless_zero(&subreq->wb_kref)) {
+ if (subreq->wb_offset == head->wb_offset + total_bytes)
+ total_bytes += subreq->wb_bytes;
+ continue;
+ }
+
+ while (!nfs_lock_request(subreq)) {
+ /*
+ * Unlock page to allow nfs_page_group_sync_on_bit()
+ * to succeed
+ */
+ nfs_page_group_unlock(head);
+ ret = nfs_wait_on_request(subreq);
+ if (!ret)
+ ret = nfs_page_group_lock(head);
+ if (ret < 0) {
+ nfs_unroll_locks(inode, head, subreq);
+ nfs_release_request(subreq);
+ nfs_unlock_and_release_request(head);
+ return ERR_PTR(ret);
+ }
+ }
/*
* Subrequests are always contiguous, non overlapping
* and in order - but may be repeated (mirrored writes).
@@ -535,24 +537,12 @@ try_again:
((subreq->wb_offset + subreq->wb_bytes) >
(head->wb_offset + total_bytes)))) {
nfs_page_group_unlock(head);
- spin_unlock(&inode->i_lock);
+ nfs_unroll_locks(inode, head, subreq);
+ nfs_unlock_and_release_request(subreq);
+ nfs_unlock_and_release_request(head);
return ERR_PTR(-EIO);
}
-
- if (!nfs_lock_request(subreq)) {
- /* releases page group bit lock and
- * inode spin lock and all references */
- ret = nfs_unroll_locks_and_wait(inode, head,
- subreq, nonblock);
-
- if (ret == 0)
- goto try_again;
-
- return ERR_PTR(ret);
- }
-
- subreq = subreq->wb_this_page;
- } while (subreq != head);
+ }
/* Now that all requests are locked, make sure they aren't on any list.
* Commit list removal accounting is done after locks are dropped */
@@ -573,34 +563,30 @@ try_again:
head->wb_bytes = total_bytes;
}
- /*
- * prepare head request to be added to new pgio descriptor
- */
- nfs_page_group_clear_bits(head);
-
- /*
- * some part of the group was still on the inode list - otherwise
- * the group wouldn't be involved in async write.
- * grab a reference for the head request, iff it needs one.
- */
- if (!test_and_set_bit(PG_INODE_REF, &head->wb_flags))
+ /* Postpone destruction of this request */
+ if (test_and_clear_bit(PG_REMOVE, &head->wb_flags)) {
+ set_bit(PG_INODE_REF, &head->wb_flags);
kref_get(&head->wb_kref);
+ atomic_long_inc(&NFS_I(inode)->nrequests);
+ }
nfs_page_group_unlock(head);
- /* drop lock to clean uprequests on destroy list */
- spin_unlock(&inode->i_lock);
+ nfs_destroy_unlinked_subrequests(destroy_list, head, inode);
- nfs_destroy_unlinked_subrequests(destroy_list, head);
+ /* Did we lose a race with nfs_inode_remove_request()? */
+ if (!(PagePrivate(page) || PageSwapCache(page))) {
+ nfs_unlock_and_release_request(head);
+ return NULL;
+ }
- /* still holds ref on head from nfs_page_find_head_request_locked
+ /* still holds ref on head from nfs_page_find_head_request
* and still has lock on head from lock loop */
return head;
}
static void nfs_write_error_remove_page(struct nfs_page *req)
{
- nfs_unlock_request(req);
nfs_end_page_writeback(req);
generic_error_remove_page(page_file_mapping(req->wb_page),
req->wb_page);
@@ -624,12 +610,12 @@ nfs_error_is_fatal_on_server(int err)
* May return an error if the user signalled nfs_wait_on_request().
*/
static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
- struct page *page, bool nonblock)
+ struct page *page)
{
struct nfs_page *req;
int ret = 0;
- req = nfs_lock_and_join_requests(page, nonblock);
+ req = nfs_lock_and_join_requests(page);
if (!req)
goto out;
ret = PTR_ERR(req);
@@ -672,7 +658,7 @@ static int nfs_do_writepage(struct page *page, struct writeback_control *wbc,
int ret;
nfs_pageio_cond_complete(pgio, page_index(page));
- ret = nfs_page_async_flush(pgio, page, wbc->sync_mode == WB_SYNC_NONE);
+ ret = nfs_page_async_flush(pgio, page);
if (ret == -EAGAIN) {
redirty_page_for_writepage(wbc, page);
ret = 0;
@@ -759,6 +745,7 @@ out_err:
*/
static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
{
+ struct address_space *mapping = page_file_mapping(req->wb_page);
struct nfs_inode *nfsi = NFS_I(inode);
WARN_ON_ONCE(req->wb_this_page != req);
@@ -766,27 +753,30 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
/* Lock the request! */
nfs_lock_request(req);
- spin_lock(&inode->i_lock);
- if (!nfsi->nrequests &&
- NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE))
- inode->i_version++;
/*
* Swap-space should not get truncated. Hence no need to plug the race
* with invalidate/truncate.
*/
+ spin_lock(&mapping->private_lock);
+ if (!nfs_have_writebacks(inode) &&
+ NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) {
+ spin_lock(&inode->i_lock);
+ inode->i_version++;
+ spin_unlock(&inode->i_lock);
+ }
if (likely(!PageSwapCache(req->wb_page))) {
set_bit(PG_MAPPED, &req->wb_flags);
SetPagePrivate(req->wb_page);
set_page_private(req->wb_page, (unsigned long)req);
}
- nfsi->nrequests++;
+ spin_unlock(&mapping->private_lock);
+ atomic_long_inc(&nfsi->nrequests);
/* this a head request for a page group - mark it as having an
* extra reference so sub groups can follow suit.
* This flag also informs pgio layer when to bump nrequests when
* adding subrequests. */
WARN_ON(test_and_set_bit(PG_INODE_REF, &req->wb_flags));
kref_get(&req->wb_kref);
- spin_unlock(&inode->i_lock);
}
/*
@@ -794,25 +784,22 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
*/
static void nfs_inode_remove_request(struct nfs_page *req)
{
- struct inode *inode = d_inode(req->wb_context->dentry);
+ struct address_space *mapping = page_file_mapping(req->wb_page);
+ struct inode *inode = mapping->host;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_page *head;
+ atomic_long_dec(&nfsi->nrequests);
if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) {
head = req->wb_head;
- spin_lock(&inode->i_lock);
+ spin_lock(&mapping->private_lock);
if (likely(head->wb_page && !PageSwapCache(head->wb_page))) {
set_page_private(head->wb_page, 0);
ClearPagePrivate(head->wb_page);
clear_bit(PG_MAPPED, &head->wb_flags);
}
- nfsi->nrequests--;
- spin_unlock(&inode->i_lock);
- } else {
- spin_lock(&inode->i_lock);
- nfsi->nrequests--;
- spin_unlock(&inode->i_lock);
+ spin_unlock(&mapping->private_lock);
}
if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags))
@@ -868,7 +855,8 @@ nfs_page_search_commits_for_head_request_locked(struct nfs_inode *nfsi,
* number of outstanding requests requiring a commit as well as
* the MM page stats.
*
- * The caller must hold cinfo->inode->i_lock, and the nfs_page lock.
+ * The caller must hold NFS_I(cinfo->inode)->commit_mutex, and the
+ * nfs_page lock.
*/
void
nfs_request_add_commit_list_locked(struct nfs_page *req, struct list_head *dst,
@@ -876,7 +864,7 @@ nfs_request_add_commit_list_locked(struct nfs_page *req, struct list_head *dst,
{
set_bit(PG_CLEAN, &req->wb_flags);
nfs_list_add_request(req, dst);
- cinfo->mds->ncommit++;
+ atomic_long_inc(&cinfo->mds->ncommit);
}
EXPORT_SYMBOL_GPL(nfs_request_add_commit_list_locked);
@@ -896,9 +884,9 @@ EXPORT_SYMBOL_GPL(nfs_request_add_commit_list_locked);
void
nfs_request_add_commit_list(struct nfs_page *req, struct nfs_commit_info *cinfo)
{
- spin_lock(&cinfo->inode->i_lock);
+ mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
nfs_request_add_commit_list_locked(req, &cinfo->mds->list, cinfo);
- spin_unlock(&cinfo->inode->i_lock);
+ mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
if (req->wb_page)
nfs_mark_page_unstable(req->wb_page, cinfo);
}
@@ -922,7 +910,7 @@ nfs_request_remove_commit_list(struct nfs_page *req,
if (!test_and_clear_bit(PG_CLEAN, &(req)->wb_flags))
return;
nfs_list_remove_request(req);
- cinfo->mds->ncommit--;
+ atomic_long_dec(&cinfo->mds->ncommit);
}
EXPORT_SYMBOL_GPL(nfs_request_remove_commit_list);
@@ -967,7 +955,7 @@ nfs_clear_page_commit(struct page *page)
WB_RECLAIMABLE);
}
-/* Called holding inode (/cinfo) lock */
+/* Called holding the request lock on @req */
static void
nfs_clear_request_commit(struct nfs_page *req)
{
@@ -976,9 +964,11 @@ nfs_clear_request_commit(struct nfs_page *req)
struct nfs_commit_info cinfo;
nfs_init_cinfo_from_inode(&cinfo, inode);
+ mutex_lock(&NFS_I(inode)->commit_mutex);
if (!pnfs_clear_request_commit(req, &cinfo)) {
nfs_request_remove_commit_list(req, &cinfo);
}
+ mutex_unlock(&NFS_I(inode)->commit_mutex);
nfs_clear_page_commit(req->wb_page);
}
}
@@ -1023,7 +1013,6 @@ static void nfs_write_completion(struct nfs_pgio_header *hdr)
remove_req:
nfs_inode_remove_request(req);
next:
- nfs_unlock_request(req);
nfs_end_page_writeback(req);
nfs_release_request(req);
}
@@ -1035,10 +1024,10 @@ out:
unsigned long
nfs_reqs_to_commit(struct nfs_commit_info *cinfo)
{
- return cinfo->mds->ncommit;
+ return atomic_long_read(&cinfo->mds->ncommit);
}
-/* cinfo->inode->i_lock held by caller */
+/* NFS_I(cinfo->inode)->commit_mutex held by caller */
int
nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
struct nfs_commit_info *cinfo, int max)
@@ -1046,20 +1035,37 @@ nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
struct nfs_page *req, *tmp;
int ret = 0;
+restart:
list_for_each_entry_safe(req, tmp, src, wb_list) {
- if (!nfs_lock_request(req))
- continue;
kref_get(&req->wb_kref);
- if (cond_resched_lock(&cinfo->inode->i_lock))
- list_safe_reset_next(req, tmp, wb_list);
+ if (!nfs_lock_request(req)) {
+ int status;
+
+ /* Prevent deadlock with nfs_lock_and_join_requests */
+ if (!list_empty(dst)) {
+ nfs_release_request(req);
+ continue;
+ }
+ /* Ensure we make progress to prevent livelock */
+ mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
+ status = nfs_wait_on_request(req);
+ nfs_release_request(req);
+ mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
+ if (status < 0)
+ break;
+ goto restart;
+ }
nfs_request_remove_commit_list(req, cinfo);
+ clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
nfs_list_add_request(req, dst);
ret++;
if ((ret == max) && !cinfo->dreq)
break;
+ cond_resched();
}
return ret;
}
+EXPORT_SYMBOL_GPL(nfs_scan_commit_list);
/*
* nfs_scan_commit - Scan an inode for commit requests
@@ -1076,15 +1082,17 @@ nfs_scan_commit(struct inode *inode, struct list_head *dst,
{
int ret = 0;
- spin_lock(&cinfo->inode->i_lock);
- if (cinfo->mds->ncommit > 0) {
+ if (!atomic_long_read(&cinfo->mds->ncommit))
+ return 0;
+ mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
+ if (atomic_long_read(&cinfo->mds->ncommit) > 0) {
const int max = INT_MAX;
ret = nfs_scan_commit_list(&cinfo->mds->list, dst,
cinfo, max);
ret += pnfs_scan_commit_lists(inode, cinfo, max - ret);
}
- spin_unlock(&cinfo->inode->i_lock);
+ mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
return ret;
}
@@ -1105,43 +1113,21 @@ static struct nfs_page *nfs_try_to_update_request(struct inode *inode,
unsigned int end;
int error;
- if (!PagePrivate(page))
- return NULL;
-
end = offset + bytes;
- spin_lock(&inode->i_lock);
-
- for (;;) {
- req = nfs_page_find_head_request_locked(NFS_I(inode), page);
- if (req == NULL)
- goto out_unlock;
- /* should be handled by nfs_flush_incompatible */
- WARN_ON_ONCE(req->wb_head != req);
- WARN_ON_ONCE(req->wb_this_page != req);
-
- rqend = req->wb_offset + req->wb_bytes;
- /*
- * Tell the caller to flush out the request if
- * the offsets are non-contiguous.
- * Note: nfs_flush_incompatible() will already
- * have flushed out requests having wrong owners.
- */
- if (offset > rqend
- || end < req->wb_offset)
- goto out_flushme;
-
- if (nfs_lock_request(req))
- break;
+ req = nfs_lock_and_join_requests(page);
+ if (IS_ERR_OR_NULL(req))
+ return req;
- /* The request is locked, so wait and then retry */
- spin_unlock(&inode->i_lock);
- error = nfs_wait_on_request(req);
- nfs_release_request(req);
- if (error != 0)
- goto out_err;
- spin_lock(&inode->i_lock);
- }
+ rqend = req->wb_offset + req->wb_bytes;
+ /*
+ * Tell the caller to flush out the request if
+ * the offsets are non-contiguous.
+ * Note: nfs_flush_incompatible() will already
+ * have flushed out requests having wrong owners.
+ */
+ if (offset > rqend || end < req->wb_offset)
+ goto out_flushme;
/* Okay, the request matches. Update the region */
if (offset < req->wb_offset) {
@@ -1152,17 +1138,17 @@ static struct nfs_page *nfs_try_to_update_request(struct inode *inode,
req->wb_bytes = end - req->wb_offset;
else
req->wb_bytes = rqend - req->wb_offset;
-out_unlock:
- if (req)
- nfs_clear_request_commit(req);
- spin_unlock(&inode->i_lock);
return req;
out_flushme:
- spin_unlock(&inode->i_lock);
- nfs_release_request(req);
+ /*
+ * Note: we mark the request dirty here because
+ * nfs_lock_and_join_requests() cannot preserve
+ * commit flags, so we have to replay the write.
+ */
+ nfs_mark_request_dirty(req);
+ nfs_unlock_and_release_request(req);
error = nfs_wb_page(inode, page);
-out_err:
- return ERR_PTR(error);
+ return (error < 0) ? ERR_PTR(error) : NULL;
}
/*
@@ -1227,8 +1213,6 @@ int nfs_flush_incompatible(struct file *file, struct page *page)
l_ctx = req->wb_lock_context;
do_flush = req->wb_page != page ||
!nfs_match_open_context(req->wb_context, ctx);
- /* for now, flush if more than 1 request in page_group */
- do_flush |= req->wb_this_page != req;
if (l_ctx && flctx &&
!(list_empty_careful(&flctx->flc_posix) &&
list_empty_careful(&flctx->flc_flock))) {
@@ -1412,7 +1396,6 @@ static void nfs_redirty_request(struct nfs_page *req)
{
nfs_mark_request_dirty(req);
set_bit(NFS_CONTEXT_RESEND_WRITES, &req->wb_context->flags);
- nfs_unlock_request(req);
nfs_end_page_writeback(req);
nfs_release_request(req);
}
@@ -1452,7 +1435,7 @@ void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
pg_ops = server->pnfs_curr_ld->pg_write_ops;
#endif
nfs_pageio_init(pgio, inode, pg_ops, compl_ops, &nfs_rw_write_ops,
- server->wsize, ioflags, GFP_NOIO);
+ server->wsize, ioflags);
}
EXPORT_SYMBOL_GPL(nfs_pageio_init_write);
@@ -1934,7 +1917,7 @@ int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
int ret = 0;
/* no commits means nothing needs to be done */
- if (!nfsi->commit_info.ncommit)
+ if (!atomic_long_read(&nfsi->commit_info.ncommit))
return ret;
if (wbc->sync_mode == WB_SYNC_NONE) {
@@ -2015,7 +1998,7 @@ int nfs_wb_page_cancel(struct inode *inode, struct page *page)
/* blocking call to cancel all requests and join to a single (head)
* request */
- req = nfs_lock_and_join_requests(page, false);
+ req = nfs_lock_and_join_requests(page);
if (IS_ERR(req)) {
ret = PTR_ERR(req);