[XFS] Move some code around to avoid prototypes and prep for future

writepages code. 

SGI-PV: 950211
SGI-Modid: xfs-linux-melb:xfs-kern:25311a

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nathan Scott <nathans@sgi.com>

1 files changed, 183 insertions, 184 deletions

diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 74d8be87f983..58fc7ade90b5 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -43,7 +43,32 @@
 #include <linux/pagevec.h>
 #include <linux/writeback.h>
 
-STATIC void xfs_count_page_state(struct page *, int *, int *, int *);
+
+STATIC void
+xfs_count_page_state(
+        struct page             *page,
+        int                     *delalloc,
+        int                     *unmapped,
+        int                     *unwritten)
+{
+        struct buffer_head      *bh, *head;
+
+        *delalloc = *unmapped = *unwritten = 0;
+
+        bh = head = page_buffers(page);
+        do {
+                if (buffer_uptodate(bh) && !buffer_mapped(bh))
+                        (*unmapped) = 1;
+                else if (buffer_unwritten(bh) && !buffer_delay(bh))
+                        clear_buffer_unwritten(bh);
+                else if (buffer_unwritten(bh))
+                        (*unwritten) = 1;
+                else if (buffer_delay(bh))
+                        (*delalloc) = 1;
+        } while ((bh = bh->b_this_page) != head);
+}
+
+
 
 #if defined(XFS_RW_TRACE)
 void
@@ -1040,6 +1065,154 @@ error:
         return err;
 }
 
+/*
+ * writepage: Called from one of two places:
+ *
+ * 1. we are flushing a delalloc buffer head.
+ *
+ * 2. we are writing out a dirty page. Typically the page dirty
+ *    state is cleared before we get here. In this case is it
+ *    conceivable we have no buffer heads.
+ *
+ * For delalloc space on the page we need to allocate space and
+ * flush it. For unmapped buffer heads on the page we should
+ * allocate space if the page is uptodate. For any other dirty
+ * buffer heads on the page we should flush them.
+ *
+ * If we detect that a transaction would be required to flush
+ * the page, we have to check the process flags first, if we
+ * are already in a transaction or disk I/O during allocations
+ * is off, we need to fail the writepage and redirty the page.
+ */
+
+STATIC int
+linvfs_writepage(
+        struct page             *page,
+        struct writeback_control *wbc)
+{
+        int                     error;
+        int                     need_trans;
+        int                     delalloc, unmapped, unwritten;
+        struct inode            *inode = page->mapping->host;
+
+        xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0);
+
+        /*
+         * We need a transaction if:
+         *  1. There are delalloc buffers on the page
+         *  2. The page is uptodate and we have unmapped buffers
+         *  3. The page is uptodate and we have no buffers
+         *  4. There are unwritten buffers on the page
+         */
+
+        if (!page_has_buffers(page)) {
+                unmapped = 1;
+                need_trans = 1;
+        } else {
+                xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
+                if (!PageUptodate(page))
+                        unmapped = 0;
+                need_trans = delalloc + unmapped + unwritten;
+        }
+
+        /*
+         * If we need a transaction and the process flags say
+         * we are already in a transaction, or no IO is allowed
+         * then mark the page dirty again and leave the page
+         * as is.
+         */
+        if (PFLAGS_TEST_FSTRANS() && need_trans)
+                goto out_fail;
+
+        /*
+         * Delay hooking up buffer heads until we have
+         * made our go/no-go decision.
+         */
+        if (!page_has_buffers(page))
+                create_empty_buffers(page, 1 << inode->i_blkbits, 0);
+
+        /*
+         * Convert delayed allocate, unwritten or unmapped space
+         * to real space and flush out to disk.
+         */
+        error = xfs_page_state_convert(inode, page, wbc, 1, unmapped);
+        if (error == -EAGAIN)
+                goto out_fail;
+        if (unlikely(error < 0))
+                goto out_unlock;
+
+        return 0;
+
+out_fail:
+        redirty_page_for_writepage(wbc, page);
+        unlock_page(page);
+        return 0;
+out_unlock:
+        unlock_page(page);
+        return error;
+}
+
+/*
+ * Called to move a page into cleanable state - and from there
+ * to be released. Possibly the page is already clean. We always
+ * have buffer heads in this call.
+ *
+ * Returns 0 if the page is ok to release, 1 otherwise.
+ *
+ * Possible scenarios are:
+ *
+ * 1. We are being called to release a page which has been written
+ *    to via regular I/O. buffer heads will be dirty and possibly
+ *    delalloc. If no delalloc buffer heads in this case then we
+ *    can just return zero.
+ *
+ * 2. We are called to release a page which has been written via
+ *    mmap, all we need to do is ensure there is no delalloc
+ *    state in the buffer heads, if not we can let the caller
+ *    free them and we should come back later via writepage.
+ */
+STATIC int
+linvfs_release_page(
+        struct page             *page,
+        gfp_t                   gfp_mask)
+{
+        struct inode            *inode = page->mapping->host;
+        int                     dirty, delalloc, unmapped, unwritten;
+        struct writeback_control wbc = {
+                .sync_mode = WB_SYNC_ALL,
+                .nr_to_write = 1,
+        };
+
+        xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, gfp_mask);
+
+        xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
+        if (!delalloc && !unwritten)
+                goto free_buffers;
+
+        if (!(gfp_mask & __GFP_FS))
+                return 0;
+
+        /* If we are already inside a transaction or the thread cannot
+         * do I/O, we cannot release this page.
+         */
+        if (PFLAGS_TEST_FSTRANS())
+                return 0;
+
+        /*
+         * Convert delalloc space to real space, do not flush the
+         * data out to disk, that will be done by the caller.
+         * Never need to allocate space here - we will always
+         * come back to writepage in that case.
+         */
+        dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0);
+        if (dirty == 0 && !unwritten)
+                goto free_buffers;
+        return 0;
+
+free_buffers:
+        return try_to_free_buffers(page);
+}
+
 STATIC int
 __linvfs_get_block(
         struct inode            *inode,
@@ -1223,6 +1396,15 @@ linvfs_direct_IO(
         return ret;
 }
 
+STATIC int
+linvfs_prepare_write(
+        struct file             *file,
+        struct page             *page,
+        unsigned int            from,
+        unsigned int            to)
+{
+        return block_prepare_write(page, from, to, linvfs_get_block);
+}
 
 STATIC sector_t
 linvfs_bmap(
@@ -1259,118 +1441,6 @@ linvfs_readpages(
         return mpage_readpages(mapping, pages, nr_pages, linvfs_get_block);
 }
 
-STATIC void
-xfs_count_page_state(
-        struct page             *page,
-        int                     *delalloc,
-        int                     *unmapped,
-        int                     *unwritten)
-{
-        struct buffer_head      *bh, *head;
-
-        *delalloc = *unmapped = *unwritten = 0;
-
-        bh = head = page_buffers(page);
-        do {
-                if (buffer_uptodate(bh) && !buffer_mapped(bh))
-                        (*unmapped) = 1;
-                else if (buffer_unwritten(bh) && !buffer_delay(bh))
-                        clear_buffer_unwritten(bh);
-                else if (buffer_unwritten(bh))
-                        (*unwritten) = 1;
-                else if (buffer_delay(bh))
-                        (*delalloc) = 1;
-        } while ((bh = bh->b_this_page) != head);
-}
-
-
-/*
- * writepage: Called from one of two places:
- *
- * 1. we are flushing a delalloc buffer head.
- *
- * 2. we are writing out a dirty page. Typically the page dirty
- *    state is cleared before we get here. In this case is it
- *    conceivable we have no buffer heads.
- *
- * For delalloc space on the page we need to allocate space and
- * flush it. For unmapped buffer heads on the page we should
- * allocate space if the page is uptodate. For any other dirty
- * buffer heads on the page we should flush them.
- *
- * If we detect that a transaction would be required to flush
- * the page, we have to check the process flags first, if we
- * are already in a transaction or disk I/O during allocations
- * is off, we need to fail the writepage and redirty the page.
- */
-
-STATIC int
-linvfs_writepage(
-        struct page             *page,
-        struct writeback_control *wbc)
-{
-        int                     error;
-        int                     need_trans;
-        int                     delalloc, unmapped, unwritten;
-        struct inode            *inode = page->mapping->host;
-
-        xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0);
-
-        /*
-         * We need a transaction if:
-         *  1. There are delalloc buffers on the page
-         *  2. The page is uptodate and we have unmapped buffers
-         *  3. The page is uptodate and we have no buffers
-         *  4. There are unwritten buffers on the page
-         */
-
-        if (!page_has_buffers(page)) {
-                unmapped = 1;
-                need_trans = 1;
-        } else {
-                xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
-                if (!PageUptodate(page))
-                        unmapped = 0;
-                need_trans = delalloc + unmapped + unwritten;
-        }
-
-        /*
-         * If we need a transaction and the process flags say
-         * we are already in a transaction, or no IO is allowed
-         * then mark the page dirty again and leave the page
-         * as is.
-         */
-        if (PFLAGS_TEST_FSTRANS() && need_trans)
-                goto out_fail;
-
-        /*
-         * Delay hooking up buffer heads until we have
-         * made our go/no-go decision.
-         */
-        if (!page_has_buffers(page))
-                create_empty_buffers(page, 1 << inode->i_blkbits, 0);
-
-        /*
-         * Convert delayed allocate, unwritten or unmapped space
-         * to real space and flush out to disk.
-         */
-        error = xfs_page_state_convert(inode, page, wbc, 1, unmapped);
-        if (error == -EAGAIN)
-                goto out_fail;
-        if (unlikely(error < 0))
-                goto out_unlock;
-
-        return 0;
-
-out_fail:
-        redirty_page_for_writepage(wbc, page);
-        unlock_page(page);
-        return 0;
-out_unlock:
-        unlock_page(page);
-        return error;
-}
-
 STATIC int
 linvfs_invalidate_page(
         struct page             *page,
@@ -1381,77 +1451,6 @@ linvfs_invalidate_page(
         return block_invalidatepage(page, offset);
 }
 
-/*
- * Called to move a page into cleanable state - and from there
- * to be released. Possibly the page is already clean. We always
- * have buffer heads in this call.
- *
- * Returns 0 if the page is ok to release, 1 otherwise.
- *
- * Possible scenarios are:
- *
- * 1. We are being called to release a page which has been written
- *    to via regular I/O. buffer heads will be dirty and possibly
- *    delalloc. If no delalloc buffer heads in this case then we
- *    can just return zero.
- *
- * 2. We are called to release a page which has been written via
- *    mmap, all we need to do is ensure there is no delalloc
- *    state in the buffer heads, if not we can let the caller
- *    free them and we should come back later via writepage.
- */
-STATIC int
-linvfs_release_page(
-        struct page             *page,
-        gfp_t                   gfp_mask)
-{
-        struct inode            *inode = page->mapping->host;
-        int                     dirty, delalloc, unmapped, unwritten;
-        struct writeback_control wbc = {
-                .sync_mode = WB_SYNC_ALL,
-                .nr_to_write = 1,
-        };
-
-        xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, gfp_mask);
-
-        xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
-        if (!delalloc && !unwritten)
-                goto free_buffers;
-
-        if (!(gfp_mask & __GFP_FS))
-                return 0;
-
-        /* If we are already inside a transaction or the thread cannot
-         * do I/O, we cannot release this page.
-         */
-        if (PFLAGS_TEST_FSTRANS())
-                return 0;
-
-        /*
-         * Convert delalloc space to real space, do not flush the
-         * data out to disk, that will be done by the caller.
-         * Never need to allocate space here - we will always
-         * come back to writepage in that case.
-         */
-        dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0);
-        if (dirty == 0 && !unwritten)
-                goto free_buffers;
-        return 0;
-
-free_buffers:
-        return try_to_free_buffers(page);
-}
-
-STATIC int
-linvfs_prepare_write(
-        struct file             *file,
-        struct page             *page,
-        unsigned int            from,
-        unsigned int            to)
-{
-        return block_prepare_write(page, from, to, linvfs_get_block);
-}
-
 struct address_space_operations linvfs_aops = {
         .readpage               = linvfs_readpage,
         .readpages              = linvfs_readpages,