Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux

[linux-2.6] / fs / gfs2 / ops_address.c

diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index 5e9653c4d8867ab2994d54044db6120b2da469d3..30c15622174fdbc59f3b94ab8cec331001b2a943 100644 (file)
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -170,7 +170,8 @@ out_ignore:
  * and write whole extents at once. This is a big reduction in the
  * number of I/O requests we send and the bmap calls we make in this case.
  */
-int gfs2_writepages(struct address_space *mapping, struct writeback_control *wbc)
+static int gfs2_writepages(struct address_space *mapping,
+                          struct writeback_control *wbc)
 {
        struct inode *inode = mapping->host;
        struct gfs2_inode *ip = GFS2_I(inode);
@@ -196,7 +197,19 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
        void *kaddr;
        int error;
 
-       BUG_ON(page->index);
+       /*
+        * Due to the order of unstuffing files and ->nopage(), we can be
+        * asked for a zero page in the case of a stuffed file being extended,
+        * so we need to supply one here. It doesn't happen often.
+        */
+       if (unlikely(page->index)) {
+               kaddr = kmap_atomic(page, KM_USER0);
+               memset(kaddr, 0, PAGE_CACHE_SIZE);
+               kunmap_atomic(kaddr, KM_USER0);
+               flush_dcache_page(page);
+               SetPageUptodate(page);
+               return 0;
+       }
 
        error = gfs2_meta_inode_buffer(ip, &dibh);
        if (error)
@@ -207,9 +220,8 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
               ip->i_di.di_size);
        memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size);
        kunmap_atomic(kaddr, KM_USER0);
-
+       flush_dcache_page(page);
        brelse(dibh);
-
        SetPageUptodate(page);
 
        return 0;
@@ -265,9 +277,11 @@ skip_lock:
 out:
        return error;
 out_unlock:
-       if (error == GLR_TRYFAILED)
-               error = AOP_TRUNCATED_PAGE;
        unlock_page(page);
+       if (error == GLR_TRYFAILED) {
+               error = AOP_TRUNCATED_PAGE;
+               yield();
+       }
        if (do_unlock)
                gfs2_holder_uninit(&gh);
        goto out;
@@ -363,6 +377,7 @@ static int gfs2_prepare_write(struct file *file, struct page *page,
                if (error == GLR_TRYFAILED) {
                        unlock_page(page);
                        error = AOP_TRUNCATED_PAGE;
+                       yield();
                }
                goto out_uninit;
        }
@@ -503,7 +518,9 @@ static int gfs2_commit_write(struct file *file, struct page *page,
                gfs2_quota_unlock(ip);
                gfs2_alloc_put(ip);
        }
+       unlock_page(page);
        gfs2_glock_dq_m(1, &ip->i_gh);
+       lock_page(page);
        gfs2_holder_uninit(&ip->i_gh);
        return 0;
 
@@ -516,7 +533,9 @@ fail_endtrans:
                gfs2_quota_unlock(ip);
                gfs2_alloc_put(ip);
        }
+       unlock_page(page);
        gfs2_glock_dq_m(1, &ip->i_gh);
+       lock_page(page);
        gfs2_holder_uninit(&ip->i_gh);
 fail_nounlock:
        ClearPageUptodate(page);