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-rw-r--r--fs/ext2/xip.c81
-rw-r--r--mm/filemap_xip.c23
2 files changed, 55 insertions, 49 deletions
diff --git a/fs/ext2/xip.c b/fs/ext2/xip.c
index d44431d1a33..0aa5ac159c0 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);
}
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index 4553b2c5aab..8c199f53773 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -68,13 +68,12 @@ do_xip_mapping_read(struct address_space *mapping,
if (unlikely(IS_ERR(page))) {
if (PTR_ERR(page) == -ENODATA) {
/* sparse */
- page = virt_to_page(empty_zero_page);
+ page = ZERO_PAGE(0);
} else {
desc->error = PTR_ERR(page);
goto out;
}
- } else
- BUG_ON(!PageUptodate(page));
+ }
/* If users can be writing to this page using arbitrary
* virtual addresses, take care about potential aliasing
@@ -84,8 +83,7 @@ do_xip_mapping_read(struct address_space *mapping,
flush_dcache_page(page);
/*
- * Ok, we have the page, and it's up-to-date, so
- * now we can copy it to user space...
+ * Ok, we have the page, so now we can copy it to user space...
*
* The actor routine returns how many bytes were actually used..
* NOTE! This may not be the same as how much of a user buffer
@@ -164,7 +162,7 @@ EXPORT_SYMBOL_GPL(xip_file_sendfile);
* xip_write
*
* This function walks all vmas of the address_space and unmaps the
- * empty_zero_page when found at pgoff. Should it go in rmap.c?
+ * ZERO_PAGE when found at pgoff. Should it go in rmap.c?
*/
static void
__xip_unmap (struct address_space * mapping,
@@ -187,7 +185,7 @@ __xip_unmap (struct address_space * mapping,
* We need the page_table_lock to protect us from page faults,
* munmap, fork, etc...
*/
- pte = page_check_address(virt_to_page(empty_zero_page), mm,
+ pte = page_check_address(ZERO_PAGE(address), mm,
address);
if (!IS_ERR(pte)) {
/* Nuke the page table entry. */
@@ -230,7 +228,6 @@ xip_file_nopage(struct vm_area_struct * area,
page = mapping->a_ops->get_xip_page(mapping, pgoff*(PAGE_SIZE/512), 0);
if (!IS_ERR(page)) {
- BUG_ON(!PageUptodate(page));
return page;
}
if (PTR_ERR(page) != -ENODATA)
@@ -245,12 +242,11 @@ xip_file_nopage(struct vm_area_struct * area,
pgoff*(PAGE_SIZE/512), 1);
if (IS_ERR(page))
return NULL;
- BUG_ON(!PageUptodate(page));
/* unmap page at pgoff from all other vmas */
__xip_unmap(mapping, pgoff);
} else {
- /* not shared and writable, use empty_zero_page */
- page = virt_to_page(empty_zero_page);
+ /* not shared and writable, use ZERO_PAGE() */
+ page = ZERO_PAGE(address);
}
return page;
@@ -319,8 +315,6 @@ __xip_file_write(struct file *filp, const char __user *buf,
break;
}
- BUG_ON(!PageUptodate(page));
-
copied = filemap_copy_from_user(page, offset, buf, bytes);
flush_dcache_page(page);
if (likely(copied > 0)) {
@@ -435,8 +429,7 @@ xip_truncate_page(struct address_space *mapping, loff_t from)
return 0;
else
return PTR_ERR(page);
- } else
- BUG_ON(!PageUptodate(page));
+ }
kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + offset, 0, length);
kunmap_atomic(kaddr, KM_USER0);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-28 20:33:03 +0000