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Date: Thu, 17 Sep 2009 17:21:47 +0200
From: Jan Kara <jack@...e.cz>
To: linux-fsdevel@...r.kernel.org
Cc: LKML <linux-kernel@...r.kernel.org>, linux-ext4@...r.kernel.org,
linux-mm@...ck.org, npiggin@...e.de, Jan Kara <jack@...e.cz>
Subject: [PATCH 7/7] ext2: Convert ext2 to new mkwrite code
Signed-off-by: Jan Kara <jack@...e.cz>
---
fs/ext2/file.c | 28 +++++++++++++++++++++++++++-
fs/ext2/inode.c | 54 ++++++++++++++++++++++++++++++++++++++++--------------
2 files changed, 67 insertions(+), 15 deletions(-)
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 806def9..317cfa0 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -19,6 +19,8 @@
*/
#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/buffer_head.h>
#include "ext2.h"
#include "xattr.h"
#include "acl.h"
@@ -38,6 +40,30 @@ static int ext2_release_file (struct inode * inode, struct file * filp)
return 0;
}
+static struct vm_operations_struct ext2_file_vm_ops = {
+ .fault = filemap_fault,
+ .page_mkwrite = noalloc_page_mkwrite,
+};
+
+static struct vm_operations_struct ext2_nobh_file_vm_ops = {
+ .fault = filemap_fault,
+};
+
+static int ext2_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct address_space *mapping = file->f_mapping;
+
+ if (!mapping->a_ops->readpage)
+ return -ENOEXEC;
+ file_accessed(file);
+ if (!test_opt(mapping->host->i_sb, NOBH))
+ vma->vm_ops = &ext2_file_vm_ops;
+ else
+ vma->vm_ops = &ext2_nobh_file_vm_ops;
+ vma->vm_flags |= VM_CAN_NONLINEAR;
+ return 0;
+}
+
/*
* We have mostly NULL's here: the current defaults are ok for
* the ext2 filesystem.
@@ -52,7 +78,7 @@ const struct file_operations ext2_file_operations = {
#ifdef CONFIG_COMPAT
.compat_ioctl = ext2_compat_ioctl,
#endif
- .mmap = generic_file_mmap,
+ .mmap = ext2_file_mmap,
.open = generic_file_open,
.release = ext2_release_file,
.fsync = simple_fsync,
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 8ff0f44..75881dd 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -815,10 +815,35 @@ ext2_nobh_write_begin(struct file *file, struct address_space *mapping,
return ret;
}
+/*
+ * This is mostly used as a fallback function for __mpage_writepage(). We have
+ * to prepare buffers for block_write_full_page() so that all the buffers that
+ * should be written are either mapped or delay.
+ */
static int ext2_nobh_writepage(struct page *page,
- struct writeback_control *wbc)
+ struct writeback_control *wbc)
{
- return nobh_writepage(page, ext2_get_block, wbc);
+ struct inode *inode = page->mapping->host;
+ int blocksize = 1 << inode->i_blkbits;
+ loff_t i_size = i_size_read(inode), start;
+ struct buffer_head *head, *bh;
+
+ if (!page_has_buffers(page)) {
+ create_empty_buffers(page, blocksize,
+ (1 << BH_Dirty)|(1 << BH_Uptodate));
+ }
+ head = bh = page_buffers(page);
+ start = page_offset(page);
+ do {
+ if (start >= i_size)
+ break;
+ if (!buffer_mapped(bh) && buffer_dirty(bh))
+ set_buffer_delay(bh);
+ start += blocksize;
+ bh = bh->b_this_page;
+ } while (bh != head);
+
+ return block_write_full_page(page, ext2_get_block, wbc);
}
static sector_t ext2_bmap(struct address_space *mapping, sector_t block)
@@ -850,6 +875,7 @@ ext2_writepages(struct address_space *mapping, struct writeback_control *wbc)
}
const struct address_space_operations ext2_aops = {
+ .new_writepage = 1,
.readpage = ext2_readpage,
.readpages = ext2_readpages,
.writepage = ext2_writepage,
@@ -864,11 +890,13 @@ const struct address_space_operations ext2_aops = {
};
const struct address_space_operations ext2_aops_xip = {
+ .new_writepage = 1,
.bmap = ext2_bmap,
.get_xip_mem = ext2_get_xip_mem,
};
const struct address_space_operations ext2_nobh_aops = {
+ .new_writepage = 1,
.readpage = ext2_readpage,
.readpages = ext2_readpages,
.writepage = ext2_nobh_writepage,
@@ -1167,7 +1195,7 @@ static void ext2_truncate_blocks(struct inode *inode, loff_t offset)
int ext2_setsize(struct inode *inode, loff_t newsize)
{
- loff_t oldsize;
+ loff_t oldsize = inode->i_size;
int error;
error = inode_newsize_ok(inode, newsize);
@@ -1182,21 +1210,19 @@ int ext2_setsize(struct inode *inode, loff_t newsize)
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
return -EPERM;
- if (mapping_is_xip(inode->i_mapping))
- error = xip_truncate_page(inode->i_mapping, newsize);
- else if (test_opt(inode->i_sb, NOBH))
- error = nobh_truncate_page(inode->i_mapping,
- newsize, ext2_get_block);
- else
- error = block_truncate_page(inode->i_mapping,
- newsize, ext2_get_block);
- if (error)
- return error;
+ if (newsize > oldsize) {
+ error = block_prepare_hole(inode, oldsize, newsize, 0,
+ ext2_get_block);
+ if (error)
+ return error;
+ }
- oldsize = inode->i_size;
i_size_write(inode, newsize);
truncate_pagecache(inode, oldsize, newsize);
+ if (newsize > oldsize)
+ block_finish_hole(inode, oldsize, newsize);
+
__ext2_truncate_blocks(inode, newsize);
inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
--
1.6.0.2
--
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