#include <linux/buffer_head.h>
#include <linux/ext2_fs_sb.h>
#include <linux/ext2_fs.h>
+#include <linux/blkdev.h>
#include "ext2.h"
#include "xip.h"
static inline int
-__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);
+__inode_direct_access(struct inode *inode, sector_t block,
+ void **kaddr, unsigned long *pfn)
+{
+ struct block_device *bdev = inode->i_sb->s_bdev;
+ struct block_device_operations *ops = bdev->bd_disk->fops;
+ sector_t sector;
+
+ sector = block * (PAGE_SIZE / 512); /* ext2 block to bdev sector */
+
+ BUG_ON(!ops->direct_access);
+ return ops->direct_access(bdev, sector, kaddr, pfn);
+}
+
+static inline int
+__ext2_get_block(struct inode *inode, pgoff_t pgoff, int create,
+ sector_t *result)
+{
+ struct buffer_head tmp;
+ int rc;
+
+ memset(&tmp, 0, sizeof(struct buffer_head));
+ rc = ext2_get_block(inode, pgoff, &tmp, create);
+ *result = tmp.b_blocknr;
+
+ /* did we get a sparse block (hole in the file)? */
+ if (!tmp.b_blocknr && !rc) {
+ BUG_ON(create);
+ rc = -ENODATA;
+ }
+
+ return rc;
}
int
-ext2_clear_xip_target(struct inode *inode, int block) {
- sector_t sector = block*(PAGE_SIZE/512);
- unsigned long data;
+ext2_clear_xip_target(struct inode *inode, sector_t block)
+{
+ void *kaddr;
+ unsigned long pfn;
int rc;
- rc = __inode_direct_access(inode, sector, &data);
- if (rc)
- return rc;
- clear_page((void*)data);
- return 0;
+ rc = __inode_direct_access(inode, block, &kaddr, &pfn);
+ if (!rc)
+ clear_page(kaddr);
+ 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, __func__,
+ "ignoring xip option - not supported by bdev");
}
}
-struct page*
-ext2_get_xip_page(struct address_space *mapping, sector_t blockno,
- int create)
+int ext2_get_xip_mem(struct address_space *mapping, pgoff_t pgoff, int create,
+ void **kmem, unsigned long *pfn)
{
int rc;
- unsigned long data;
- struct buffer_head tmp;
+ sector_t block;
- 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_block(mapping->host, pgoff, create, &block);
if (rc)
- return ERR_PTR(rc);
- if (tmp.b_blocknr == 0) {
- /* SPARSE block */
- BUG_ON(create);
- return ERR_PTR(-ENODATA);
- }
-
- rc = __inode_direct_access
- (mapping->host,tmp.b_blocknr*(PAGE_SIZE/512) ,&data);
- if (rc)
- return ERR_PTR(rc);
+ return rc;
- SetPageUptodate(virt_to_page(data));
- return virt_to_page(data);
+ /* retrieve address of the target data */
+ rc = __inode_direct_access(mapping->host, block, kmem, pfn);
+ return rc;
}