NFS: Flesh out nfs_invalidate_page()

In the case of a call to truncate_inode_pages(), we should really try to
cancel any pending writes on the page.

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

1 files changed, 28 insertions, 19 deletions

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 106aca388ebc..656481c0daa3 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -325,6 +325,7 @@ out:
 
 /**
  * nfs_scan_list - Scan a list for matching requests
+ * @nfsi: NFS inode
  * @head: One of the NFS inode request lists
  * @dst: Destination list
  * @idx_start: lower bound of page->index to scan
@@ -336,14 +337,15 @@ out:
  * The requests are *not* checked to ensure that they form a contiguous set.
  * You must be holding the inode's req_lock when calling this function
  */
-int
-nfs_scan_list(struct list_head *head, struct list_head *dst,
-              unsigned long idx_start, unsigned int npages)
+int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *head,
+                struct list_head *dst, unsigned long idx_start,
+                unsigned int npages)
 {
-        struct list_head        *pos, *tmp;
-        struct nfs_page         *req;
-        unsigned long           idx_end;
-        int                     res;
+        struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
+        struct nfs_page *req;
+        unsigned long idx_end;
+        int found, i;
+        int res;
 
         res = 0;
         if (npages == 0)
@@ -351,21 +353,28 @@ nfs_scan_list(struct list_head *head, struct list_head *dst,
         else
                 idx_end = idx_start + npages - 1;
 
-        list_for_each_safe(pos, tmp, head) {
-
-                req = nfs_list_entry(pos);
-
-                if (req->wb_index < idx_start)
-                        continue;
-                if (req->wb_index > idx_end)
+        for (;;) {
+                found = radix_tree_gang_lookup(&nfsi->nfs_page_tree,
+                                (void **)&pgvec[0], idx_start,
+                                NFS_SCAN_MAXENTRIES);
+                if (found <= 0)
                         break;
+                for (i = 0; i < found; i++) {
+                        req = pgvec[i];
+                        if (req->wb_index > idx_end)
+                                goto out;
+                        idx_start = req->wb_index + 1;
+                        if (req->wb_list_head != head)
+                                continue;
+                        if (nfs_set_page_writeback_locked(req)) {
+                                nfs_list_remove_request(req);
+                                nfs_list_add_request(req, dst);
+                                res++;
+                        }
+                }
 
-                if (!nfs_set_page_writeback_locked(req))
-                        continue;
-                nfs_list_remove_request(req);
-                nfs_list_add_request(req, dst);
-                res++;
         }
+out:
         return res;
 }