1 files changed, 31 insertions, 36 deletions

diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index c02f7c5b7462..6cbbd165c60d 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -372,7 +372,7 @@ static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
  * assumes that all buffers on the page are started at the same time.
  *
  * The fix is two passes across the ioend list - one to start writeback on the
- * bufferheads, and then the second one submit them for I/O.
+ * buffer_heads, and then submit them for I/O on the second pass.
  */
 STATIC void
 xfs_submit_ioend(
@@ -699,7 +699,7 @@ xfs_convert_page(
 
         /*
          * page_dirty is initially a count of buffers on the page before
-         * EOF and is decrememted as we move each into a cleanable state.
+         * EOF and is decremented as we move each into a cleanable state.
          *
          * Derivation:
          *
@@ -842,7 +842,7 @@ xfs_cluster_write(
  * page if possible.
  * The bh->b_state's cannot know if any of the blocks or which block for
  * that matter are dirty due to mmap writes, and therefore bh uptodate is
- * only vaild if the page itself isn't completely uptodate.  Some layers
+ * only valid if the page itself isn't completely uptodate.  Some layers
  * may clear the page dirty flag prior to calling write page, under the
  * assumption the entire page will be written out; by not writing out the
  * whole page the page can be reused before all valid dirty data is
@@ -892,7 +892,7 @@ xfs_page_state_convert(
 
         /*
          * page_dirty is initially a count of buffers on the page before
-         * EOF and is decrememted as we move each into a cleanable state.
+         * EOF and is decremented as we move each into a cleanable state.
          *
          * Derivation:
          *
@@ -1223,10 +1223,9 @@ free_buffers:
 }
 
 STATIC int
-__xfs_get_block(
+__xfs_get_blocks(
         struct inode            *inode,
         sector_t                iblock,
-        unsigned long           blocks,
         struct buffer_head      *bh_result,
         int                     create,
         int                     direct,
@@ -1236,22 +1235,17 @@ __xfs_get_block(
         xfs_iomap_t             iomap;
         xfs_off_t               offset;
         ssize_t                 size;
-        int                     retpbbm = 1;
+        int                     niomap = 1;
         int                     error;
 
         offset = (xfs_off_t)iblock << inode->i_blkbits;
-        if (blocks)
-                size = (ssize_t) min_t(xfs_off_t, LONG_MAX,
-                                        (xfs_off_t)blocks << inode->i_blkbits);
-        else
-                size = 1 << inode->i_blkbits;
-
+        ASSERT(bh_result->b_size >= (1 << inode->i_blkbits));
+        size = bh_result->b_size;
         VOP_BMAP(vp, offset, size,
-                create ? flags : BMAPI_READ, &iomap, &retpbbm, error);
+                create ? flags : BMAPI_READ, &iomap, &niomap, error);
         if (error)
                 return -error;
-
-        if (retpbbm == 0)
+        if (niomap == 0)
                 return 0;
 
         if (iomap.iomap_bn != IOMAP_DADDR_NULL) {
@@ -1271,12 +1265,16 @@ __xfs_get_block(
                 }
         }
 
-        /* If this is a realtime file, data might be on a new device */
+        /*
+         * If this is a realtime file, data may be on a different device.
+         * to that pointed to from the buffer_head b_bdev currently.
+         */
         bh_result->b_bdev = iomap.iomap_target->bt_bdev;
 
-        /* If we previously allocated a block out beyond eof and
-         * we are now coming back to use it then we will need to
-         * flag it as new even if it has a disk address.
+        /*
+         * If we previously allocated a block out beyond eof and we are
+         * now coming back to use it then we will need to flag it as new
+         * even if it has a disk address.
          */
         if (create &&
             ((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
@@ -1292,26 +1290,24 @@ __xfs_get_block(
                 }
         }
 
-        if (blocks) {
+        if (direct || size > (1 << inode->i_blkbits)) {
                 ASSERT(iomap.iomap_bsize - iomap.iomap_delta > 0);
                 offset = min_t(xfs_off_t,
-                                iomap.iomap_bsize - iomap.iomap_delta,
-                                (xfs_off_t)blocks << inode->i_blkbits);
-                bh_result->b_size = (u32) min_t(xfs_off_t, UINT_MAX, offset);
+                                iomap.iomap_bsize - iomap.iomap_delta, size);
+                bh_result->b_size = (ssize_t)min_t(xfs_off_t, LONG_MAX, offset);
         }
 
         return 0;
 }
 
 int
-xfs_get_block(
+xfs_get_blocks(
         struct inode            *inode,
         sector_t                iblock,
         struct buffer_head      *bh_result,
         int                     create)
 {
-        return __xfs_get_block(inode, iblock,
-                                bh_result->b_size >> inode->i_blkbits,
+        return __xfs_get_blocks(inode, iblock,
                                 bh_result, create, 0, BMAPI_WRITE);
 }
 
@@ -1322,8 +1318,7 @@ xfs_get_blocks_direct(
         struct buffer_head      *bh_result,
         int                     create)
 {
-        return __xfs_get_block(inode, iblock,
-                                bh_result->b_size >> inode->i_blkbits,
+        return __xfs_get_blocks(inode, iblock,
                                 bh_result, create, 1, BMAPI_WRITE|BMAPI_DIRECT);
 }
 
@@ -1339,9 +1334,9 @@ xfs_end_io_direct(
         /*
          * Non-NULL private data means we need to issue a transaction to
          * convert a range from unwritten to written extents.  This needs
-         * to happen from process contect but aio+dio I/O completion
+         * to happen from process context but aio+dio I/O completion
          * happens from irq context so we need to defer it to a workqueue.
-         * This is not nessecary for synchronous direct I/O, but we do
+         * This is not necessary for synchronous direct I/O, but we do
          * it anyway to keep the code uniform and simpler.
          *
          * The core direct I/O code might be changed to always call the
@@ -1358,7 +1353,7 @@ xfs_end_io_direct(
         }
 
         /*
-         * blockdev_direct_IO can return an error even afer the I/O
+         * blockdev_direct_IO can return an error even after the I/O
          * completion handler was called.  Thus we need to protect
          * against double-freeing.
          */
@@ -1405,7 +1400,7 @@ xfs_vm_prepare_write(
         unsigned int            from,
         unsigned int            to)
 {
-        return block_prepare_write(page, from, to, xfs_get_block);
+        return block_prepare_write(page, from, to, xfs_get_blocks);
 }
 
 STATIC sector_t
@@ -1422,7 +1417,7 @@ xfs_vm_bmap(
         VOP_RWLOCK(vp, VRWLOCK_READ);
         VOP_FLUSH_PAGES(vp, (xfs_off_t)0, -1, 0, FI_REMAPF, error);
         VOP_RWUNLOCK(vp, VRWLOCK_READ);
-        return generic_block_bmap(mapping, block, xfs_get_block);
+        return generic_block_bmap(mapping, block, xfs_get_blocks);
 }
 
 STATIC int
@@ -1430,7 +1425,7 @@ xfs_vm_readpage(
         struct file             *unused,
         struct page             *page)
 {
-        return mpage_readpage(page, xfs_get_block);
+        return mpage_readpage(page, xfs_get_blocks);
 }
 
 STATIC int
@@ -1440,7 +1435,7 @@ xfs_vm_readpages(
         struct list_head        *pages,
         unsigned                nr_pages)
 {
-        return mpage_readpages(mapping, pages, nr_pages, xfs_get_block);
+        return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
 }
 
 STATIC void