NFS: Another cleanup of the read/write request coalescing code

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 20 insertions, 33 deletions

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index b03ec1ba4d75..b6749967eead 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -835,7 +835,7 @@ static void nfs_execute_write(struct nfs_write_data *data)
  * Generate multiple small requests to write out a single
  * contiguous dirty area on one page.
  */
-static int nfs_flush_multi(struct inode *inode, struct list_head *head, int how)
+static int nfs_flush_multi(struct inode *inode, struct list_head *head, size_t count, int how)
 {
         struct nfs_page *req = nfs_list_entry(head->next);
         struct page *page = req->wb_page;
@@ -847,7 +847,7 @@ static int nfs_flush_multi(struct inode *inode, struct list_head *head, int how)
 
         nfs_list_remove_request(req);
 
-        nbytes = req->wb_bytes;
+        nbytes = count;
         do {
                 size_t len = min(nbytes, wsize);
 
@@ -862,23 +862,19 @@ static int nfs_flush_multi(struct inode *inode, struct list_head *head, int how)
 
         ClearPageError(page);
         offset = 0;
-        nbytes = req->wb_bytes;
+        nbytes = count;
         do {
                 data = list_entry(list.next, struct nfs_write_data, pages);
                 list_del_init(&data->pages);
 
                 data->pagevec[0] = page;
 
-                if (nbytes > wsize) {
-                        nfs_write_rpcsetup(req, data, &nfs_write_partial_ops,
-                                        wsize, offset, how);
-                        offset += wsize;
-                        nbytes -= wsize;
-                } else {
-                        nfs_write_rpcsetup(req, data, &nfs_write_partial_ops,
-                                        nbytes, offset, how);
-                        nbytes = 0;
-                }
+                if (nbytes < wsize)
+                        wsize = nbytes;
+                nfs_write_rpcsetup(req, data, &nfs_write_partial_ops,
+                                   wsize, offset, how);
+                offset += wsize;
+                nbytes -= wsize;
                 nfs_execute_write(data);
         } while (nbytes != 0);
 
@@ -904,26 +900,23 @@ out_bad:
  * This is the case if nfs_updatepage detects a conflicting request
  * that has been written but not committed.
  */
-static int nfs_flush_one(struct inode *inode, struct list_head *head, int how)
+static int nfs_flush_one(struct inode *inode, struct list_head *head, size_t count, int how)
 {
         struct nfs_page         *req;
         struct page             **pages;
         struct nfs_write_data   *data;
-        unsigned int            count;
 
-        data = nfs_writedata_alloc(NFS_SERVER(inode)->wsize);
+        data = nfs_writedata_alloc(count);
         if (!data)
                 goto out_bad;
 
         pages = data->pagevec;
-        count = 0;
         while (!list_empty(head)) {
                 req = nfs_list_entry(head->next);
                 nfs_list_remove_request(req);
                 nfs_list_add_request(req, &data->pages);
                 ClearPageError(req->wb_page);
                 *pages++ = req->wb_page;
-                count += req->wb_bytes;
         }
         req = nfs_list_entry(data->pages.next);
 
@@ -946,28 +939,22 @@ static int nfs_flush_one(struct inode *inode, struct list_head *head, int how)
 static int nfs_flush_list(struct inode *inode, struct list_head *head, int npages, int how)
 {
         struct nfs_pageio_descriptor desc;
-        int (*flush_one)(struct inode *, struct list_head *, int);
         int wpages = NFS_SERVER(inode)->wpages;
         int wsize = NFS_SERVER(inode)->wsize;
-        int error;
 
-        flush_one = nfs_flush_one;
-        if (wsize < PAGE_CACHE_SIZE)
-                flush_one = nfs_flush_multi;
         /* For single writes, FLUSH_STABLE is more efficient */
         if (npages <= wpages && npages == NFS_I(inode)->npages
                         && nfs_list_entry(head->next)->wb_bytes <= wsize)
                 how |= FLUSH_STABLE;
 
-        do {
-                nfs_pageio_init(&desc, wsize);
-                nfs_pageio_add_list(&desc, head);
-                error = flush_one(inode, &desc.pg_list, how);
-                if (error < 0)
-                        goto out_err;
-        } while (!list_empty(head));
-        return 0;
-out_err:
+        if (wsize < PAGE_CACHE_SIZE)
+                nfs_pageio_init(&desc, inode, nfs_flush_multi, wsize, how);
+        else
+                nfs_pageio_init(&desc, inode, nfs_flush_one, wsize, how);
+        nfs_pageio_add_list(&desc, head);
+        nfs_pageio_complete(&desc);
+        if (desc.pg_error == 0)
+                return 0;
         while (!list_empty(head)) {
                 struct nfs_page *req = nfs_list_entry(head->next);
                 nfs_list_remove_request(req);
@@ -975,7 +962,7 @@ out_err:
                 nfs_end_page_writeback(req->wb_page);
                 nfs_clear_page_writeback(req);
         }
-        return error;
+        return desc.pg_error;
 }
 
 /*