NFS: Add nfs_set_page_dirty()
We will want to allow nfs_writepage() to distinguish between pages that
have been marked as dirty by the VM, and those that have been marked as
dirty by nfs_updatepage().
In the former case, the entire page will want to be written out, and so any
requests that were pending need to be flushed out first.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 143a190..c2fe3bd 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -331,7 +331,7 @@
const struct address_space_operations nfs_file_aops = {
.readpage = nfs_readpage,
.readpages = nfs_readpages,
- .set_page_dirty = __set_page_dirty_nobuffers,
+ .set_page_dirty = nfs_set_page_dirty,
.writepage = nfs_writepage,
.writepages = nfs_writepages,
.prepare_write = nfs_prepare_write,
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index f0720b5..266fea7 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -251,16 +251,23 @@
{
struct nfs_open_context *ctx;
struct inode *inode = page->mapping->host;
+ struct nfs_page *req;
unsigned offset;
- int err;
+ int err = 0;
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1);
- /* Ensure we've flushed out any previous writes */
- nfs_wb_page_priority(inode, page, wb_priority(wbc));
+ 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));
+ }
- err = 0;
offset = nfs_page_length(page);
if (!offset)
goto out;
@@ -655,7 +662,7 @@
{
struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data;
struct nfs_page *req;
- int status = 0;
+ int do_flush, status;
/*
* Look for a request corresponding to this page. If there
* is one, and it belongs to another file, we flush it out
@@ -664,15 +671,18 @@
* Also do the same if we find a request from an existing
* dropped page.
*/
- req = nfs_page_find_request(page);
- if (req != NULL) {
- int do_flush = req->wb_page != page || req->wb_context != ctx;
-
+ do {
+ req = nfs_page_find_request(page);
+ if (req == NULL)
+ return 0;
+ do_flush = req->wb_page != page || req->wb_context != ctx
+ || test_bit(PG_NEED_FLUSH, &req->wb_flags);
nfs_release_request(req);
- if (do_flush)
- status = nfs_wb_page(page->mapping->host, page);
- }
- return (status < 0) ? status : 0;
+ if (!do_flush)
+ return 0;
+ status = nfs_wb_page(page->mapping->host, page);
+ } while (status == 0);
+ return status;
}
/*
@@ -1437,6 +1447,19 @@
return nfs_wb_page_priority(inode, page, 0);
}
+int nfs_set_page_dirty(struct page *page)
+{
+ struct nfs_page *req;
+
+ req = nfs_page_find_request(page);
+ if (req != NULL) {
+ /* Mark any existing write requests for flushing */
+ set_bit(PG_NEED_FLUSH, &req->wb_flags);
+ nfs_release_request(req);
+ }
+ return __set_page_dirty_nobuffers(page);
+}
+
int __init nfs_init_writepagecache(void)
{
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index f2ec9be..1b38c20 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -427,6 +427,7 @@
extern int nfs_updatepage(struct file *, struct page *, unsigned int, unsigned int);
extern int nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
extern void nfs_writedata_release(void *);
+extern int nfs_set_page_dirty(struct page *);
/*
* Try to write back everything synchronously (but check the
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index 38aa15f..d111be6 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -30,6 +30,7 @@
#define PG_BUSY 0
#define PG_NEED_COMMIT 1
#define PG_NEED_RESCHED 2
+#define PG_NEED_FLUSH 3
struct nfs_inode;
struct nfs_page {
