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authorCarsten Otte <cotte@de.ibm.com>2005-07-15 03:56:30 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2005-07-15 09:54:50 -0700
commitafa597ba20e9ef55fc6283c1a564854b1c9f13c0 (patch)
tree56cbfbca20a3c59ef6b1d149f67185e8e8f3a85c /fs/ext2/xip.c
parentc5287ba132ff742e595d42c28b66cbba19522c4e (diff)
downloadop-kernel-dev-afa597ba20e9ef55fc6283c1a564854b1c9f13c0.zip
op-kernel-dev-afa597ba20e9ef55fc6283c1a564854b1c9f13c0.tar.gz
[PATCH] execute-in-place fixes
This patch includes feedback from Andrew and Christoph. Thanks for taking time to review. Use of empty_zero_page was eliminated to fix compilation for architectures that don't have it. This patch removes setting pages up-to-date in ext2_get_xip_page and all bug checks to verify that the page is indeed up to date. Setting the page state on mapping to userland is bogus. None of the code patchs involved with these pages in mm cares about the page state. still on my ToDo list: identify a place outside second extended where __inode_direct_access should reside Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/ext2/xip.c')
-rw-r--r--fs/ext2/xip.c81
1 files changed, 47 insertions, 34 deletions
diff --git a/fs/ext2/xip.c b/fs/ext2/xip.c
index d44431d..0aa5ac159 100644
--- a/fs/ext2/xip.c
+++ b/fs/ext2/xip.c
@@ -15,66 +15,79 @@
#include "xip.h"
static inline int
-__inode_direct_access(struct inode *inode, sector_t sector, unsigned long *data) {
+__inode_direct_access(struct inode *inode, sector_t sector,
+ unsigned long *data)
+{
BUG_ON(!inode->i_sb->s_bdev->bd_disk->fops->direct_access);
return inode->i_sb->s_bdev->bd_disk->fops
->direct_access(inode->i_sb->s_bdev,sector,data);
}
+static inline int
+__ext2_get_sector(struct inode *inode, sector_t offset, int create,
+ sector_t *result)
+{
+ struct buffer_head tmp;
+ int rc;
+
+ memset(&tmp, 0, sizeof(struct buffer_head));
+ rc = ext2_get_block(inode, offset/ (PAGE_SIZE/512), &tmp,
+ create);
+ *result = tmp.b_blocknr;
+
+ /* did we get a sparse block (hole in the file)? */
+ if (!(*result)) {
+ BUG_ON(create);
+ rc = -ENODATA;
+ }
+
+ return rc;
+}
+
int
-ext2_clear_xip_target(struct inode *inode, int block) {
- sector_t sector = block*(PAGE_SIZE/512);
+ext2_clear_xip_target(struct inode *inode, int block)
+{
+ sector_t sector = block * (PAGE_SIZE/512);
unsigned long data;
int rc;
rc = __inode_direct_access(inode, sector, &data);
- if (rc)
- return rc;
- clear_page((void*)data);
- return 0;
+ if (!rc)
+ clear_page((void*)data);
+ return rc;
}
void ext2_xip_verify_sb(struct super_block *sb)
{
struct ext2_sb_info *sbi = EXT2_SB(sb);
- if ((sbi->s_mount_opt & EXT2_MOUNT_XIP)) {
- if ((sb->s_bdev == NULL) ||
- sb->s_bdev->bd_disk == NULL ||
- sb->s_bdev->bd_disk->fops == NULL ||
- sb->s_bdev->bd_disk->fops->direct_access == NULL) {
- sbi->s_mount_opt &= (~EXT2_MOUNT_XIP);
- ext2_warning(sb, __FUNCTION__,
- "ignoring xip option - not supported by bdev");
- }
+ if ((sbi->s_mount_opt & EXT2_MOUNT_XIP) &&
+ !sb->s_bdev->bd_disk->fops->direct_access) {
+ sbi->s_mount_opt &= (~EXT2_MOUNT_XIP);
+ ext2_warning(sb, __FUNCTION__,
+ "ignoring xip option - not supported by bdev");
}
}
-struct page*
-ext2_get_xip_page(struct address_space *mapping, sector_t blockno,
+struct page *
+ext2_get_xip_page(struct address_space *mapping, sector_t offset,
int create)
{
int rc;
unsigned long data;
- struct buffer_head tmp;
+ sector_t sector;
- tmp.b_state = 0;
- tmp.b_blocknr = 0;
- rc = ext2_get_block(mapping->host, blockno/(PAGE_SIZE/512) , &tmp,
- create);
+ /* first, retrieve the sector number */
+ rc = __ext2_get_sector(mapping->host, offset, create, &sector);
if (rc)
- return ERR_PTR(rc);
- if (tmp.b_blocknr == 0) {
- /* SPARSE block */
- BUG_ON(create);
- return ERR_PTR(-ENODATA);
- }
+ goto error;
+ /* retrieve address of the target data */
rc = __inode_direct_access
- (mapping->host,tmp.b_blocknr*(PAGE_SIZE/512) ,&data);
- if (rc)
- return ERR_PTR(rc);
+ (mapping->host, sector * (PAGE_SIZE/512), &data);
+ if (!rc)
+ return virt_to_page(data);
- SetPageUptodate(virt_to_page(data));
- return virt_to_page(data);
+ error:
+ return ERR_PTR(rc);
}
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