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-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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