Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw: (56 commits)
  [GFS2] Allow journal recovery on read-only mount
  [GFS2] Lockup on error
  [GFS2] Fix page_mkwrite truncation race path
  [GFS2] Fix typo
  [GFS2] Fix write alloc required shortcut calculation
  [GFS2] gfs2_alloc_required performance
  [GFS2] Remove unneeded i_spin
  [GFS2] Reduce inode size by moving i_alloc out of line
  [GFS2] Fix assert in log code
  [GFS2] Fix problems relating to execution of files on GFS2
  [GFS2] Initialize extent_list earlier
  [GFS2] Allow page migration for writeback and ordered pages
  [GFS2] Remove unused variable
  [GFS2] Fix log block mapper
  [GFS2] Minor correction
  [GFS2] Eliminate the no longer needed sd_statfs_mutex
  [GFS2] Incremental patch to fix compiler warning
  [GFS2] Function meta_read optimization
  [GFS2] Only fetch the dinode once in block_map
  [GFS2] Reorganize function gfs2_glmutex_lock
  ...

1 files changed, 469 insertions, 180 deletions

diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index 9679f8b9870d..38dbe99a30ed 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -20,6 +20,8 @@
 #include <linux/swap.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/lm_interface.h>
+#include <linux/backing-dev.h>
+#include <linux/pagevec.h>
 
 #include "gfs2.h"
 #include "incore.h"
@@ -32,7 +34,6 @@
 #include "quota.h"
 #include "trans.h"
 #include "rgrp.h"
-#include "ops_file.h"
 #include "super.h"
 #include "util.h"
 #include "glops.h"
@@ -58,22 +59,6 @@ static void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
 }
 
 /**
- * gfs2_get_block - Fills in a buffer head with details about a block
- * @inode: The inode
- * @lblock: The block number to look up
- * @bh_result: The buffer head to return the result in
- * @create: Non-zero if we may add block to the file
- *
- * Returns: errno
- */
-
-int gfs2_get_block(struct inode *inode, sector_t lblock,
-                   struct buffer_head *bh_result, int create)
-{
-        return gfs2_block_map(inode, lblock, create, bh_result);
-}
-
-/**
  * gfs2_get_block_noalloc - Fills in a buffer head with details about a block
  * @inode: The inode
  * @lblock: The block number to look up
@@ -88,7 +73,7 @@ static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
 {
         int error;
 
-        error = gfs2_block_map(inode, lblock, 0, bh_result);
+        error = gfs2_block_map(inode, lblock, bh_result, 0);
         if (error)
                 return error;
         if (!buffer_mapped(bh_result))
@@ -99,20 +84,19 @@ static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
 static int gfs2_get_block_direct(struct inode *inode, sector_t lblock,
                                  struct buffer_head *bh_result, int create)
 {
-        return gfs2_block_map(inode, lblock, 0, bh_result);
+        return gfs2_block_map(inode, lblock, bh_result, 0);
 }
 
 /**
- * gfs2_writepage - Write complete page
- * @page: Page to write
+ * gfs2_writepage_common - Common bits of writepage
+ * @page: The page to be written
+ * @wbc: The writeback control
  *
- * Returns: errno
- *
- * Some of this is copied from block_write_full_page() although we still
- * call it to do most of the work.
+ * Returns: 1 if writepage is ok, otherwise an error code or zero if no error.
  */
 
-static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
+static int gfs2_writepage_common(struct page *page,
+                                 struct writeback_control *wbc)
 {
         struct inode *inode = page->mapping->host;
         struct gfs2_inode *ip = GFS2_I(inode);
@@ -120,41 +104,133 @@ static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
         loff_t i_size = i_size_read(inode);
         pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
         unsigned offset;
-        int error;
-        int done_trans = 0;
+        int ret = -EIO;
 
-        if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) {
-                unlock_page(page);
-                return -EIO;
-        }
+        if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
+                goto out;
+        ret = 0;
         if (current->journal_info)
-                goto out_ignore;
-
+                goto redirty;
         /* Is the page fully outside i_size? (truncate in progress) */
-        offset = i_size & (PAGE_CACHE_SIZE-1);
+        offset = i_size & (PAGE_CACHE_SIZE-1);
         if (page->index > end_index || (page->index == end_index && !offset)) {
                 page->mapping->a_ops->invalidatepage(page, 0);
-                unlock_page(page);
-                return 0; /* don't care */
+                goto out;
+        }
+        return 1;
+redirty:
+        redirty_page_for_writepage(wbc, page);
+out:
+        unlock_page(page);
+        return 0;
+}
+
+/**
+ * gfs2_writeback_writepage - Write page for writeback mappings
+ * @page: The page
+ * @wbc: The writeback control
+ *
+ */
+
+static int gfs2_writeback_writepage(struct page *page,
+                                    struct writeback_control *wbc)
+{
+        int ret;
+
+        ret = gfs2_writepage_common(page, wbc);
+        if (ret <= 0)
+                return ret;
+
+        ret = mpage_writepage(page, gfs2_get_block_noalloc, wbc);
+        if (ret == -EAGAIN)
+                ret = block_write_full_page(page, gfs2_get_block_noalloc, wbc);
+        return ret;
+}
+
+/**
+ * gfs2_ordered_writepage - Write page for ordered data files
+ * @page: The page to write
+ * @wbc: The writeback control
+ *
+ */
+
+static int gfs2_ordered_writepage(struct page *page,
+                                  struct writeback_control *wbc)
+{
+        struct inode *inode = page->mapping->host;
+        struct gfs2_inode *ip = GFS2_I(inode);
+        int ret;
+
+        ret = gfs2_writepage_common(page, wbc);
+        if (ret <= 0)
+                return ret;
+
+        if (!page_has_buffers(page)) {
+                create_empty_buffers(page, inode->i_sb->s_blocksize,
+                                     (1 << BH_Dirty)|(1 << BH_Uptodate));
         }
+        gfs2_page_add_databufs(ip, page, 0, inode->i_sb->s_blocksize-1);
+        return block_write_full_page(page, gfs2_get_block_noalloc, wbc);
+}
 
-        if ((sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) &&
-            PageChecked(page)) {
+/**
+ * __gfs2_jdata_writepage - The core of jdata writepage
+ * @page: The page to write
+ * @wbc: The writeback control
+ *
+ * This is shared between writepage and writepages and implements the
+ * core of the writepage operation. If a transaction is required then
+ * PageChecked will have been set and the transaction will have
+ * already been started before this is called.
+ */
+
+static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
+{
+        struct inode *inode = page->mapping->host;
+        struct gfs2_inode *ip = GFS2_I(inode);
+        struct gfs2_sbd *sdp = GFS2_SB(inode);
+
+        if (PageChecked(page)) {
                 ClearPageChecked(page);
-                error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
-                if (error)
-                        goto out_ignore;
                 if (!page_has_buffers(page)) {
                         create_empty_buffers(page, inode->i_sb->s_blocksize,
                                              (1 << BH_Dirty)|(1 << BH_Uptodate));
                 }
                 gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1);
+        }
+        return block_write_full_page(page, gfs2_get_block_noalloc, wbc);
+}
+
+/**
+ * gfs2_jdata_writepage - Write complete page
+ * @page: Page to write
+ *
+ * Returns: errno
+ *
+ */
+
+static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
+{
+        struct inode *inode = page->mapping->host;
+        struct gfs2_sbd *sdp = GFS2_SB(inode);
+        int error;
+        int done_trans = 0;
+
+        error = gfs2_writepage_common(page, wbc);
+        if (error <= 0)
+                return error;
+
+        if (PageChecked(page)) {
+                if (wbc->sync_mode != WB_SYNC_ALL)
+                        goto out_ignore;
+                error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
+                if (error)
+                        goto out_ignore;
                 done_trans = 1;
         }
-        error = block_write_full_page(page, gfs2_get_block_noalloc, wbc);
+        error = __gfs2_jdata_writepage(page, wbc);
         if (done_trans)
                 gfs2_trans_end(sdp);
-        gfs2_meta_cache_flush(ip);
         return error;
 
 out_ignore:
@@ -164,29 +240,190 @@ out_ignore:
 }
 
 /**
- * gfs2_writepages - Write a bunch of dirty pages back to disk
+ * gfs2_writeback_writepages - Write a bunch of dirty pages back to disk
  * @mapping: The mapping to write
  * @wbc: Write-back control
  *
- * For journaled files and/or ordered writes this just falls back to the
- * kernel's default writepages path for now. We will probably want to change
- * that eventually (i.e. when we look at allocate on flush).
- *
- * For the data=writeback case though we can already ignore buffer heads
+ * For the data=writeback case we can already ignore buffer heads
  * 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.
  */
-static int gfs2_writepages(struct address_space *mapping,
-                           struct writeback_control *wbc)
+static int gfs2_writeback_writepages(struct address_space *mapping,
+                                     struct writeback_control *wbc)
+{
+        return mpage_writepages(mapping, wbc, gfs2_get_block_noalloc);
+}
+
+/**
+ * gfs2_write_jdata_pagevec - Write back a pagevec's worth of pages
+ * @mapping: The mapping
+ * @wbc: The writeback control
+ * @writepage: The writepage function to call for each page
+ * @pvec: The vector of pages
+ * @nr_pages: The number of pages to write
+ *
+ * Returns: non-zero if loop should terminate, zero otherwise
+ */
+
+static int gfs2_write_jdata_pagevec(struct address_space *mapping,
+                                    struct writeback_control *wbc,
+                                    struct pagevec *pvec,
+                                    int nr_pages, pgoff_t end)
 {
         struct inode *inode = mapping->host;
-        struct gfs2_inode *ip = GFS2_I(inode);
         struct gfs2_sbd *sdp = GFS2_SB(inode);
+        loff_t i_size = i_size_read(inode);
+        pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+        unsigned offset = i_size & (PAGE_CACHE_SIZE-1);
+        unsigned nrblocks = nr_pages * (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize);
+        struct backing_dev_info *bdi = mapping->backing_dev_info;
+        int i;
+        int ret;
+
+        ret = gfs2_trans_begin(sdp, nrblocks, 0);
+        if (ret < 0)
+                return ret;
+
+        for(i = 0; i < nr_pages; i++) {
+                struct page *page = pvec->pages[i];
+
+                lock_page(page);
+
+                if (unlikely(page->mapping != mapping)) {
+                        unlock_page(page);
+                        continue;
+                }
+
+                if (!wbc->range_cyclic && page->index > end) {
+                        ret = 1;
+                        unlock_page(page);
+                        continue;
+                }
+
+                if (wbc->sync_mode != WB_SYNC_NONE)
+                        wait_on_page_writeback(page);
+
+                if (PageWriteback(page) ||
+                    !clear_page_dirty_for_io(page)) {
+                        unlock_page(page);
+                        continue;
+                }
+
+                /* Is the page fully outside i_size? (truncate in progress) */
+                if (page->index > end_index || (page->index == end_index && !offset)) {
+                        page->mapping->a_ops->invalidatepage(page, 0);
+                        unlock_page(page);
+                        continue;
+                }
+
+                ret = __gfs2_jdata_writepage(page, wbc);
+
+                if (ret || (--(wbc->nr_to_write) <= 0))
+                        ret = 1;
+                if (wbc->nonblocking && bdi_write_congested(bdi)) {
+                        wbc->encountered_congestion = 1;
+                        ret = 1;
+                }
+
+        }
+        gfs2_trans_end(sdp);
+        return ret;
+}
+
+/**
+ * gfs2_write_cache_jdata - Like write_cache_pages but different
+ * @mapping: The mapping to write
+ * @wbc: The writeback control
+ * @writepage: The writepage function to call
+ * @data: The data to pass to writepage
+ *
+ * The reason that we use our own function here is that we need to
+ * start transactions before we grab page locks. This allows us
+ * to get the ordering right.
+ */
+
+static int gfs2_write_cache_jdata(struct address_space *mapping,
+                                  struct writeback_control *wbc)
+{
+        struct backing_dev_info *bdi = mapping->backing_dev_info;
+        int ret = 0;
+        int done = 0;
+        struct pagevec pvec;
+        int nr_pages;
+        pgoff_t index;
+        pgoff_t end;
+        int scanned = 0;
+        int range_whole = 0;
+
+        if (wbc->nonblocking && bdi_write_congested(bdi)) {
+                wbc->encountered_congestion = 1;
+                return 0;
+        }
+
+        pagevec_init(&pvec, 0);
+        if (wbc->range_cyclic) {
+                index = mapping->writeback_index; /* Start from prev offset */
+                end = -1;
+        } else {
+                index = wbc->range_start >> PAGE_CACHE_SHIFT;
+                end = wbc->range_end >> PAGE_CACHE_SHIFT;
+                if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
+                        range_whole = 1;
+                scanned = 1;
+        }
 
-        if (sdp->sd_args.ar_data == GFS2_DATA_WRITEBACK && !gfs2_is_jdata(ip))
-                return mpage_writepages(mapping, wbc, gfs2_get_block_noalloc);
+retry:
+         while (!done && (index <= end) &&
+                (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+                                               PAGECACHE_TAG_DIRTY,
+                                               min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
+                scanned = 1;
+                ret = gfs2_write_jdata_pagevec(mapping, wbc, &pvec, nr_pages, end);
+                if (ret)
+                        done = 1;
+                if (ret > 0)
+                        ret = 0;
+
+                pagevec_release(&pvec);
+                cond_resched();
+        }
+
+        if (!scanned && !done) {
+                /*
+                 * We hit the last page and there is more work to be done: wrap
+                 * back to the start of the file
+                 */
+                scanned = 1;
+                index = 0;
+                goto retry;
+        }
+
+        if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
+                mapping->writeback_index = index;
+        return ret;
+}
+
+
+/**
+ * gfs2_jdata_writepages - Write a bunch of dirty pages back to disk
+ * @mapping: The mapping to write
+ * @wbc: The writeback control
+ * 
+ */
 
-        return generic_writepages(mapping, wbc);
+static int gfs2_jdata_writepages(struct address_space *mapping,
+                                 struct writeback_control *wbc)
+{
+        struct gfs2_inode *ip = GFS2_I(mapping->host);
+        struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
+        int ret;
+
+        ret = gfs2_write_cache_jdata(mapping, wbc);
+        if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) {
+                gfs2_log_flush(sdp, ip->i_gl);
+                ret = gfs2_write_cache_jdata(mapping, wbc);
+        }
+        return ret;
 }
 
 /**
@@ -231,62 +468,107 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
 
 
 /**
- * gfs2_readpage - readpage with locking
- * @file: The file to read a page for. N.B. This may be NULL if we are
- * reading an internal file.
+ * __gfs2_readpage - readpage
+ * @file: The file to read a page for
  * @page: The page to read
  *
- * Returns: errno
+ * This is the core of gfs2's readpage. Its used by the internal file
+ * reading code as in that case we already hold the glock. Also its
+ * called by gfs2_readpage() once the required lock has been granted.
+ *
  */
 
-static int gfs2_readpage(struct file *file, struct page *page)
+static int __gfs2_readpage(void *file, struct page *page)
 {
         struct gfs2_inode *ip = GFS2_I(page->mapping->host);
         struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
-        struct gfs2_file *gf = NULL;
-        struct gfs2_holder gh;
         int error;
-        int do_unlock = 0;
-
-        if (likely(file != &gfs2_internal_file_sentinel)) {
-                if (file) {
-                        gf = file->private_data;
-                        if (test_bit(GFF_EXLOCK, &gf->f_flags))
-                                /* gfs2_sharewrite_fault has grabbed the ip->i_gl already */
-                                goto skip_lock;
-                }
-                gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|LM_FLAG_TRY_1CB, &gh);
-                do_unlock = 1;
-                error = gfs2_glock_nq_atime(&gh);
-                if (unlikely(error))
-                        goto out_unlock;
-        }
 
-skip_lock:
         if (gfs2_is_stuffed(ip)) {
                 error = stuffed_readpage(ip, page);
                 unlock_page(page);
-        } else
-                error = mpage_readpage(page, gfs2_get_block);
+        } else {
+                error = mpage_readpage(page, gfs2_block_map);
+        }
 
         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
-                error = -EIO;
+                return -EIO;
+
+        return error;
+}
+
+/**
+ * gfs2_readpage - read a page of a file
+ * @file: The file to read
+ * @page: The page of the file
+ *
+ * This deals with the locking required. We use a trylock in order to
+ * avoid the page lock / glock ordering problems returning AOP_TRUNCATED_PAGE
+ * in the event that we are unable to get the lock.
+ */
+
+static int gfs2_readpage(struct file *file, struct page *page)
+{
+        struct gfs2_inode *ip = GFS2_I(page->mapping->host);
+        struct gfs2_holder gh;
+        int error;
 
-        if (do_unlock) {
-                gfs2_glock_dq_m(1, &gh);
-                gfs2_holder_uninit(&gh);
+        gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|LM_FLAG_TRY_1CB, &gh);
+        error = gfs2_glock_nq_atime(&gh);
+        if (unlikely(error)) {
+                unlock_page(page);
+                goto out;
         }
+        error = __gfs2_readpage(file, page);
+        gfs2_glock_dq(&gh);
 out:
-        return error;
-out_unlock:
-        unlock_page(page);
+        gfs2_holder_uninit(&gh);
         if (error == GLR_TRYFAILED) {
-                error = AOP_TRUNCATED_PAGE;
                 yield();
+                return AOP_TRUNCATED_PAGE;
         }
-        if (do_unlock)
-                gfs2_holder_uninit(&gh);
-        goto out;
+        return error;
+}
+
+/**
+ * gfs2_internal_read - read an internal file
+ * @ip: The gfs2 inode
+ * @ra_state: The readahead state (or NULL for no readahead)
+ * @buf: The buffer to fill
+ * @pos: The file position
+ * @size: The amount to read
+ *
+ */
+
+int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state,
+                       char *buf, loff_t *pos, unsigned size)
+{
+        struct address_space *mapping = ip->i_inode.i_mapping;
+        unsigned long index = *pos / PAGE_CACHE_SIZE;
+        unsigned offset = *pos & (PAGE_CACHE_SIZE - 1);
+        unsigned copied = 0;
+        unsigned amt;
+        struct page *page;
+        void *p;
+
+        do {
+                amt = size - copied;
+                if (offset + size > PAGE_CACHE_SIZE)
+                        amt = PAGE_CACHE_SIZE - offset;
+                page = read_cache_page(mapping, index, __gfs2_readpage, NULL);
+                if (IS_ERR(page))
+                        return PTR_ERR(page);
+                p = kmap_atomic(page, KM_USER0);
+                memcpy(buf + copied, p + offset, amt);
+                kunmap_atomic(p, KM_USER0);
+                mark_page_accessed(page);
+                page_cache_release(page);
+                copied += amt;
+                index++;
+                offset = 0;
+        } while(copied < size);
+        (*pos) += size;
+        return size;
 }
 
 /**
@@ -300,10 +582,9 @@ out_unlock:
  *    Any I/O we ignore at this time will be done via readpage later.
  * 2. We don't handle stuffed files here we let readpage do the honours.
  * 3. mpage_readpages() does most of the heavy lifting in the common case.
- * 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places.
- * 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as
- *    well as read-ahead.
+ * 4. gfs2_block_map() is relied upon to set BH_Boundary in the right places.
  */
+
 static int gfs2_readpages(struct file *file, struct address_space *mapping,
                           struct list_head *pages, unsigned nr_pages)
 {
@@ -311,42 +592,20 @@ static int gfs2_readpages(struct file *file, struct address_space *mapping,
         struct gfs2_inode *ip = GFS2_I(inode);
         struct gfs2_sbd *sdp = GFS2_SB(inode);
         struct gfs2_holder gh;
-        int ret = 0;
-        int do_unlock = 0;
+        int ret;
 
-        if (likely(file != &gfs2_internal_file_sentinel)) {
-                if (file) {
-                        struct gfs2_file *gf = file->private_data;
-                        if (test_bit(GFF_EXLOCK, &gf->f_flags))
-                                goto skip_lock;
-                }
-                gfs2_holder_init(ip->i_gl, LM_ST_SHARED,
-                                 LM_FLAG_TRY_1CB|GL_ATIME, &gh);
-                do_unlock = 1;
-                ret = gfs2_glock_nq_atime(&gh);
-                if (ret == GLR_TRYFAILED)
-                        goto out_noerror;
-                if (unlikely(ret))
-                        goto out_unlock;
-        }
-skip_lock:
+        gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
+        ret = gfs2_glock_nq_atime(&gh);
+        if (unlikely(ret))
+                goto out_uninit;
         if (!gfs2_is_stuffed(ip))
-                ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block);
-
-        if (do_unlock) {
-                gfs2_glock_dq_m(1, &gh);
-                gfs2_holder_uninit(&gh);
-        }
-out:
+                ret = mpage_readpages(mapping, pages, nr_pages, gfs2_block_map);
+        gfs2_glock_dq(&gh);
+out_uninit:
+        gfs2_holder_uninit(&gh);
         if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
                 ret = -EIO;
         return ret;
-out_noerror:
-        ret = 0;
-out_unlock:
-        if (do_unlock)
-                gfs2_holder_uninit(&gh);
-        goto out;
 }
 
 /**
@@ -382,20 +641,11 @@ static int gfs2_write_begin(struct file *file, struct address_space *mapping,
         if (unlikely(error))
                 goto out_uninit;
 
-        error = -ENOMEM;
-        page = __grab_cache_page(mapping, index);
-        *pagep = page;
-        if (!page)
-                goto out_unlock;
-
         gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);
-
         error = gfs2_write_alloc_required(ip, pos, len, &alloc_required);
         if (error)
-                goto out_putpage;
-
+                goto out_unlock;
 
-        ip->i_alloc.al_requested = 0;
         if (alloc_required) {
                 al = gfs2_alloc_get(ip);
 
@@ -424,40 +674,47 @@ static int gfs2_write_begin(struct file *file, struct address_space *mapping,
         if (error)
                 goto out_trans_fail;
 
+        error = -ENOMEM;
+        page = __grab_cache_page(mapping, index);
+        *pagep = page;
+        if (unlikely(!page))
+                goto out_endtrans;
+
         if (gfs2_is_stuffed(ip)) {
+                error = 0;
                 if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
                         error = gfs2_unstuff_dinode(ip, page);
                         if (error == 0)
                                 goto prepare_write;
-                } else if (!PageUptodate(page))
+                } else if (!PageUptodate(page)) {
                         error = stuffed_readpage(ip, page);
+                }
                 goto out;
         }
 
 prepare_write:
-        error = block_prepare_write(page, from, to, gfs2_get_block);
-
+        error = block_prepare_write(page, from, to, gfs2_block_map);
 out:
-        if (error) {
-                gfs2_trans_end(sdp);
+        if (error == 0)
+                return 0;
+
+        page_cache_release(page);
+        if (pos + len > ip->i_inode.i_size)
+                vmtruncate(&ip->i_inode, ip->i_inode.i_size);
+out_endtrans:
+        gfs2_trans_end(sdp);
 out_trans_fail:
-                if (alloc_required) {
-                        gfs2_inplace_release(ip);
+        if (alloc_required) {
+                gfs2_inplace_release(ip);
 out_qunlock:
-                        gfs2_quota_unlock(ip);
+                gfs2_quota_unlock(ip);
 out_alloc_put:
-                        gfs2_alloc_put(ip);
-                }
-out_putpage:
-                page_cache_release(page);
-                if (pos + len > ip->i_inode.i_size)
-                        vmtruncate(&ip->i_inode, ip->i_inode.i_size);
+                gfs2_alloc_put(ip);
+        }
 out_unlock:
-                gfs2_glock_dq_m(1, &ip->i_gh);
+        gfs2_glock_dq(&ip->i_gh);
 out_uninit:
-                gfs2_holder_uninit(&ip->i_gh);
-        }
-
+        gfs2_holder_uninit(&ip->i_gh);
         return error;
 }
 
@@ -565,7 +822,7 @@ static int gfs2_write_end(struct file *file, struct address_space *mapping,
         struct gfs2_inode *ip = GFS2_I(inode);
         struct gfs2_sbd *sdp = GFS2_SB(inode);
         struct buffer_head *dibh;
-        struct gfs2_alloc *al = &ip->i_alloc;
+        struct gfs2_alloc *al = ip->i_alloc;
         struct gfs2_dinode *di;
         unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
         unsigned int to = from + len;
@@ -585,19 +842,16 @@ static int gfs2_write_end(struct file *file, struct address_space *mapping,
         if (gfs2_is_stuffed(ip))
                 return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);
 
-        if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
+        if (!gfs2_is_writeback(ip))
                 gfs2_page_add_databufs(ip, page, from, to);
 
         ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
 
-        if (likely(ret >= 0)) {
-                copied = ret;
-                if  ((pos + copied) > inode->i_size) {
-                        di = (struct gfs2_dinode *)dibh->b_data;
-                        ip->i_di.di_size = inode->i_size;
-                        di->di_size = cpu_to_be64(inode->i_size);
-                        mark_inode_dirty(inode);
-                }
+        if (likely(ret >= 0) && (inode->i_size > ip->i_di.di_size)) {
+                di = (struct gfs2_dinode *)dibh->b_data;
+                ip->i_di.di_size = inode->i_size;
+                di->di_size = cpu_to_be64(inode->i_size);
+                mark_inode_dirty(inode);
         }
 
         if (inode == sdp->sd_rindex)
@@ -606,7 +860,7 @@ static int gfs2_write_end(struct file *file, struct address_space *mapping,
         brelse(dibh);
         gfs2_trans_end(sdp);
 failed:
-        if (al->al_requested) {
+        if (al) {
                 gfs2_inplace_release(ip);
                 gfs2_quota_unlock(ip);
                 gfs2_alloc_put(ip);
@@ -625,11 +879,7 @@ failed:
  
 static int gfs2_set_page_dirty(struct page *page)
 {
-        struct gfs2_inode *ip = GFS2_I(page->mapping->host);
-        struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
-
-        if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
-                SetPageChecked(page);
+        SetPageChecked(page);
         return __set_page_dirty_buffers(page);
 }
 
@@ -653,7 +903,7 @@ static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock)
                 return 0;
 
         if (!gfs2_is_stuffed(ip))
-                dblock = generic_block_bmap(mapping, lblock, gfs2_get_block);
+                dblock = generic_block_bmap(mapping, lblock, gfs2_block_map);
 
         gfs2_glock_dq_uninit(&i_gh);
 
@@ -719,13 +969,9 @@ static int gfs2_ok_for_dio(struct gfs2_inode *ip, int rw, loff_t offset)
 {
         /*
          * Should we return an error here? I can't see that O_DIRECT for
-         * a journaled file makes any sense. For now we'll silently fall
-         * back to buffered I/O, likewise we do the same for stuffed
-         * files since they are (a) small and (b) unaligned.
+         * a stuffed file makes any sense. For now we'll silently fall
+         * back to buffered I/O
          */
-        if (gfs2_is_jdata(ip))
-                return 0;
-
         if (gfs2_is_stuffed(ip))
                 return 0;
 
@@ -836,9 +1082,23 @@ cannot_release:
         return 0;
 }
 
-const struct address_space_operations gfs2_file_aops = {
-        .writepage = gfs2_writepage,
-        .writepages = gfs2_writepages,
+static const struct address_space_operations gfs2_writeback_aops = {
+        .writepage = gfs2_writeback_writepage,
+        .writepages = gfs2_writeback_writepages,
+        .readpage = gfs2_readpage,
+        .readpages = gfs2_readpages,
+        .sync_page = block_sync_page,
+        .write_begin = gfs2_write_begin,
+        .write_end = gfs2_write_end,
+        .bmap = gfs2_bmap,
+        .invalidatepage = gfs2_invalidatepage,
+        .releasepage = gfs2_releasepage,
+        .direct_IO = gfs2_direct_IO,
+        .migratepage = buffer_migrate_page,
+};
+
+static const struct address_space_operations gfs2_ordered_aops = {
+        .writepage = gfs2_ordered_writepage,
         .readpage = gfs2_readpage,
         .readpages = gfs2_readpages,
         .sync_page = block_sync_page,
@@ -849,5 +1109,34 @@ const struct address_space_operations gfs2_file_aops = {
         .invalidatepage = gfs2_invalidatepage,
         .releasepage = gfs2_releasepage,
         .direct_IO = gfs2_direct_IO,
+        .migratepage = buffer_migrate_page,
 };
 
+static const struct address_space_operations gfs2_jdata_aops = {
+        .writepage = gfs2_jdata_writepage,
+        .writepages = gfs2_jdata_writepages,
+        .readpage = gfs2_readpage,
+        .readpages = gfs2_readpages,
+        .sync_page = block_sync_page,
+        .write_begin = gfs2_write_begin,
+        .write_end = gfs2_write_end,
+        .set_page_dirty = gfs2_set_page_dirty,
+        .bmap = gfs2_bmap,
+        .invalidatepage = gfs2_invalidatepage,
+        .releasepage = gfs2_releasepage,
+};
+
+void gfs2_set_aops(struct inode *inode)
+{
+        struct gfs2_inode *ip = GFS2_I(inode);
+
+        if (gfs2_is_writeback(ip))
+                inode->i_mapping->a_ops = &gfs2_writeback_aops;
+        else if (gfs2_is_ordered(ip))
+                inode->i_mapping->a_ops = &gfs2_ordered_aops;
+        else if (gfs2_is_jdata(ip))
+                inode->i_mapping->a_ops = &gfs2_jdata_aops;
+        else
+                BUG();
+}
+