gfs2: convert to new aops
authorSteven Whitehouse <swhiteho@redhat.com>
Tue, 16 Oct 2007 08:25:07 +0000 (01:25 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Tue, 16 Oct 2007 16:42:55 +0000 (09:42 -0700)
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/gfs2/ops_address.c

index 873a511ef2bea93b273aa20404f44fee8d1a410b..9679f8b9870d4b662a9a49023fc8b604ade25a68 100644 (file)
@@ -17,6 +17,7 @@
 #include <linux/mpage.h>
 #include <linux/fs.h>
 #include <linux/writeback.h>
+#include <linux/swap.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/lm_interface.h>
 
@@ -349,45 +350,49 @@ out_unlock:
 }
 
 /**
- * gfs2_prepare_write - Prepare to write a page to a file
+ * gfs2_write_begin - Begin to write to a file
  * @file: The file to write to
- * @page: The page which is to be prepared for writing
- * @from: From (byte range within page)
- * @to: To (byte range within page)
+ * @mapping: The mapping in which to write
+ * @pos: The file offset at which to start writing
+ * @len: Length of the write
+ * @flags: Various flags
+ * @pagep: Pointer to return the page
+ * @fsdata: Pointer to return fs data (unused by GFS2)
  *
  * Returns: errno
  */
 
-static int gfs2_prepare_write(struct file *file, struct page *page,
-                             unsigned from, unsigned to)
+static int gfs2_write_begin(struct file *file, struct address_space *mapping,
+                           loff_t pos, unsigned len, unsigned flags,
+                           struct page **pagep, void **fsdata)
 {
-       struct gfs2_inode *ip = GFS2_I(page->mapping->host);
-       struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
+       struct gfs2_inode *ip = GFS2_I(mapping->host);
+       struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
        unsigned int data_blocks, ind_blocks, rblocks;
        int alloc_required;
        int error = 0;
-       loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from;
-       loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
        struct gfs2_alloc *al;
-       unsigned int write_len = to - from;
+       pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+       unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+       unsigned to = from + len;
+       struct page *page;
 
-
-       gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|LM_FLAG_TRY_1CB, &ip->i_gh);
+       gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME, &ip->i_gh);
        error = gfs2_glock_nq_atime(&ip->i_gh);
-       if (unlikely(error)) {
-               if (error == GLR_TRYFAILED) {
-                       unlock_page(page);
-                       error = AOP_TRUNCATED_PAGE;
-                       yield();
-               }
+       if (unlikely(error))
                goto out_uninit;
-       }
 
-       gfs2_write_calc_reserv(ip, write_len, &data_blocks, &ind_blocks);
+       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, write_len, &alloc_required);
+       error = gfs2_write_alloc_required(ip, pos, len, &alloc_required);
        if (error)
-               goto out_unlock;
+               goto out_putpage;
 
 
        ip->i_alloc.al_requested = 0;
@@ -420,7 +425,7 @@ static int gfs2_prepare_write(struct file *file, struct page *page,
                goto out_trans_fail;
 
        if (gfs2_is_stuffed(ip)) {
-               if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
+               if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
                        error = gfs2_unstuff_dinode(ip, page);
                        if (error == 0)
                                goto prepare_write;
@@ -443,6 +448,10 @@ out_qunlock:
 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);
 out_unlock:
                gfs2_glock_dq_m(1, &ip->i_gh);
 out_uninit:
@@ -478,65 +487,117 @@ static void adjust_fs_space(struct inode *inode)
 }
 
 /**
- * gfs2_commit_write - Commit write to a file
+ * gfs2_stuffed_write_end - Write end for stuffed files
+ * @inode: The inode
+ * @dibh: The buffer_head containing the on-disk inode
+ * @pos: The file position
+ * @len: The length of the write
+ * @copied: How much was actually copied by the VFS
+ * @page: The page
+ *
+ * This copies the data from the page into the inode block after
+ * the inode data structure itself.
+ *
+ * Returns: errno
+ */
+static int gfs2_stuffed_write_end(struct inode *inode, struct buffer_head *dibh,
+                                 loff_t pos, unsigned len, unsigned copied,
+                                 struct page *page)
+{
+       struct gfs2_inode *ip = GFS2_I(inode);
+       struct gfs2_sbd *sdp = GFS2_SB(inode);
+       u64 to = pos + copied;
+       void *kaddr;
+       unsigned char *buf = dibh->b_data + sizeof(struct gfs2_dinode);
+       struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
+
+       BUG_ON((pos + len) > (dibh->b_size - sizeof(struct gfs2_dinode)));
+       kaddr = kmap_atomic(page, KM_USER0);
+       memcpy(buf + pos, kaddr + pos, copied);
+       memset(kaddr + pos + copied, 0, len - copied);
+       flush_dcache_page(page);
+       kunmap_atomic(kaddr, KM_USER0);
+
+       if (!PageUptodate(page))
+               SetPageUptodate(page);
+       unlock_page(page);
+       page_cache_release(page);
+
+       if (inode->i_size < to) {
+               i_size_write(inode, to);
+               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)
+               adjust_fs_space(inode);
+
+       brelse(dibh);
+       gfs2_trans_end(sdp);
+       gfs2_glock_dq(&ip->i_gh);
+       gfs2_holder_uninit(&ip->i_gh);
+       return copied;
+}
+
+/**
+ * gfs2_write_end
  * @file: The file to write to
- * @page: The page containing the data
- * @from: From (byte range within page)
- * @to: To (byte range within page)
+ * @mapping: The address space to write to
+ * @pos: The file position
+ * @len: The length of the data
+ * @copied:
+ * @page: The page that has been written
+ * @fsdata: The fsdata (unused in GFS2)
+ *
+ * The main write_end function for GFS2. We have a separate one for
+ * stuffed files as they are slightly different, otherwise we just
+ * put our locking around the VFS provided functions.
  *
  * Returns: errno
  */
 
-static int gfs2_commit_write(struct file *file, struct page *page,
-                            unsigned from, unsigned to)
+static int gfs2_write_end(struct file *file, struct address_space *mapping,
+                         loff_t pos, unsigned len, unsigned copied,
+                         struct page *page, void *fsdata)
 {
        struct inode *inode = page->mapping->host;
        struct gfs2_inode *ip = GFS2_I(inode);
        struct gfs2_sbd *sdp = GFS2_SB(inode);
-       int error = -EOPNOTSUPP;
        struct buffer_head *dibh;
        struct gfs2_alloc *al = &ip->i_alloc;
        struct gfs2_dinode *di;
+       unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
+       unsigned int to = from + len;
+       int ret;
 
-       if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)))
-                goto fail_nounlock;
+       BUG_ON(gfs2_glock_is_locked_by_me(ip->i_gl) == 0);
 
-       error = gfs2_meta_inode_buffer(ip, &dibh);
-       if (error)
-               goto fail_endtrans;
+       ret = gfs2_meta_inode_buffer(ip, &dibh);
+       if (unlikely(ret)) {
+               unlock_page(page);
+               page_cache_release(page);
+               goto failed;
+       }
 
        gfs2_trans_add_bh(ip->i_gl, dibh, 1);
-       di = (struct gfs2_dinode *)dibh->b_data;
-
-       if (gfs2_is_stuffed(ip)) {
-               u64 file_size;
-               void *kaddr;
 
-               file_size = ((u64)page->index << PAGE_CACHE_SHIFT) + to;
+       if (gfs2_is_stuffed(ip))
+               return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);
 
-               kaddr = kmap_atomic(page, KM_USER0);
-               memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from,
-                      kaddr + from, to - from);
-               kunmap_atomic(kaddr, KM_USER0);
+       if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
+               gfs2_page_add_databufs(ip, page, from, to);
 
-               SetPageUptodate(page);
+       ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
 
-               if (inode->i_size < file_size) {
-                       i_size_write(inode, file_size);
+       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);
                }
-       } else {
-               if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED ||
-                   gfs2_is_jdata(ip))
-                       gfs2_page_add_databufs(ip, page, from, to);
-               error = generic_commit_write(file, page, from, to);
-               if (error)
-                       goto fail;
-       }
-
-       if (ip->i_di.di_size < inode->i_size) {
-               ip->i_di.di_size = inode->i_size;
-               di->di_size = cpu_to_be64(inode->i_size);
        }
 
        if (inode == sdp->sd_rindex)
@@ -544,33 +605,15 @@ static int gfs2_commit_write(struct file *file, struct page *page,
 
        brelse(dibh);
        gfs2_trans_end(sdp);
+failed:
        if (al->al_requested) {
                gfs2_inplace_release(ip);
                gfs2_quota_unlock(ip);
                gfs2_alloc_put(ip);
        }
-       unlock_page(page);
-       gfs2_glock_dq_m(1, &ip->i_gh);
-       lock_page(page);
+       gfs2_glock_dq(&ip->i_gh);
        gfs2_holder_uninit(&ip->i_gh);
-       return 0;
-
-fail:
-       brelse(dibh);
-fail_endtrans:
-       gfs2_trans_end(sdp);
-       if (al->al_requested) {
-               gfs2_inplace_release(ip);
-               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);
-       return error;
+       return ret;
 }
 
 /**
@@ -799,8 +842,8 @@ const struct address_space_operations gfs2_file_aops = {
        .readpage = gfs2_readpage,
        .readpages = gfs2_readpages,
        .sync_page = block_sync_page,
-       .prepare_write = gfs2_prepare_write,
-       .commit_write = gfs2_commit_write,
+       .write_begin = gfs2_write_begin,
+       .write_end = gfs2_write_end,
        .set_page_dirty = gfs2_set_page_dirty,
        .bmap = gfs2_bmap,
        .invalidatepage = gfs2_invalidatepage,