NFS: Make nfs_updatepage() mark the page as dirty.
This will ensure that we can call set_page_writeback() from within
nfs_writepage(), which is always called with the page lock set.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 0eca6a54..130528d 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -77,6 +77,7 @@
static struct nfs_page * nfs_update_request(struct nfs_open_context*,
struct page *,
unsigned int, unsigned int);
+static void nfs_mark_request_dirty(struct nfs_page *req);
static int nfs_wait_on_write_congestion(struct address_space *, int);
static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int);
static long nfs_flush_mapping(struct address_space *mapping, struct writeback_control *wbc, int how);
@@ -245,29 +246,64 @@
}
/*
+ * Find an associated nfs write request, and prepare to flush it out
+ * Returns 1 if there was no write request, or if the request was
+ * already tagged by nfs_set_page_dirty.Returns 0 if the request
+ * was not tagged.
+ * May also return an error if the user signalled nfs_wait_on_request().
+ */
+static int nfs_page_mark_flush(struct page *page)
+{
+ struct nfs_page *req;
+ spinlock_t *req_lock = &NFS_I(page->mapping->host)->req_lock;
+ int ret;
+
+ spin_lock(req_lock);
+ for(;;) {
+ req = nfs_page_find_request_locked(page);
+ if (req == NULL) {
+ spin_unlock(req_lock);
+ return 1;
+ }
+ if (nfs_lock_request_dontget(req))
+ break;
+ /* Note: If we hold the page lock, as is the case in nfs_writepage,
+ * then the call to nfs_lock_request_dontget() will always
+ * succeed provided that someone hasn't already marked the
+ * request as dirty (in which case we don't care).
+ */
+ spin_unlock(req_lock);
+ ret = nfs_wait_on_request(req);
+ nfs_release_request(req);
+ if (ret != 0)
+ return ret;
+ spin_lock(req_lock);
+ }
+ spin_unlock(req_lock);
+ if (test_and_set_bit(PG_FLUSHING, &req->wb_flags) == 0)
+ nfs_mark_request_dirty(req);
+ ret = test_bit(PG_NEED_FLUSH, &req->wb_flags);
+ nfs_unlock_request(req);
+ return ret;
+}
+
+/*
* Write an mmapped page to the server.
*/
static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
{
struct nfs_open_context *ctx;
struct inode *inode = page->mapping->host;
- struct nfs_page *req;
unsigned offset;
- int err = 0;
+ int err;
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1);
- req = nfs_page_find_request(page);
- if (req != NULL) {
- int flushme = test_bit(PG_NEED_FLUSH, &req->wb_flags);
- nfs_release_request(req);
- if (!flushme)
- goto out;
- /* Ensure we've flushed out the invalid write */
- nfs_wb_page_priority(inode, page, wb_priority(wbc) | FLUSH_STABLE | FLUSH_NOWRITEPAGE);
- }
-
+ err = nfs_page_mark_flush(page);
+ if (err <= 0)
+ goto out;
+ err = 0;
offset = nfs_page_length(page);
if (!offset)
goto out;
@@ -279,7 +315,11 @@
}
err = nfs_writepage_setup(ctx, page, 0, offset);
put_nfs_open_context(ctx);
-
+ if (err != 0)
+ goto out;
+ err = nfs_page_mark_flush(page);
+ if (err > 0)
+ err = 0;
out:
if (!wbc->for_writepages)
nfs_flush_mapping(page->mapping, wbc, wb_priority(wbc));
@@ -409,8 +449,7 @@
static inline int
nfs_dirty_request(struct nfs_page *req)
{
- struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode);
- return !list_empty(&req->wb_list) && req->wb_list_head == &nfsi->dirty;
+ return test_bit(PG_FLUSHING, &req->wb_flags) == 0;
}
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
@@ -628,7 +667,6 @@
return ERR_PTR(error);
}
spin_unlock(&nfsi->req_lock);
- nfs_mark_request_dirty(new);
return new;
}
spin_unlock(&nfsi->req_lock);
@@ -684,7 +722,7 @@
if (req == NULL)
return 0;
do_flush = req->wb_page != page || req->wb_context != ctx
- || test_bit(PG_NEED_FLUSH, &req->wb_flags);
+ || !nfs_dirty_request(req);
nfs_release_request(req);
if (!do_flush)
return 0;
@@ -723,6 +761,7 @@
}
status = nfs_writepage_setup(ctx, page, offset, count);
+ __set_page_dirty_nobuffers(page);
dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n",
status, (long long)i_size_read(inode));