diff options
| author | Michael Halcrow <mhalcrow@us.ibm.com> | 2008-02-06 12:38:32 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-06 21:41:12 +0300 |
| commit | cc11beffdf80ca31dff21422fa2a5e54d25f1494 (patch) | |
| tree | 3b0e28d18f493a7c59b089c4c6fc59c79945937e /fs/ecryptfs/mmap.c | |
| parent | 7896b631823c6e8f1a520d89390624a51445840e (diff) | |
| download | linux-cc11beffdf80ca31dff21422fa2a5e54d25f1494.tar.xz | |
eCryptfs: track header bytes rather than extents
Remove internal references to header extents; just keep track of header bytes
instead. Headers can easily span multiple pages with the recent persistent
file changes.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/ecryptfs/mmap.c')
| -rw-r--r-- | fs/ecryptfs/mmap.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 9a5e0d17f1c5..dc74b186145d 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -100,13 +100,14 @@ static void set_header_info(char *page_virt, struct ecryptfs_crypt_stat *crypt_stat) { size_t written; - int save_num_header_extents_at_front = - crypt_stat->num_header_extents_at_front; + size_t save_num_header_bytes_at_front = + crypt_stat->num_header_bytes_at_front; - crypt_stat->num_header_extents_at_front = 1; + crypt_stat->num_header_bytes_at_front = + ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE; ecryptfs_write_header_metadata(page_virt + 20, crypt_stat, &written); - crypt_stat->num_header_extents_at_front = - save_num_header_extents_at_front; + crypt_stat->num_header_bytes_at_front = + save_num_header_bytes_at_front; } /** @@ -132,8 +133,11 @@ ecryptfs_copy_up_encrypted_with_header(struct page *page, loff_t view_extent_num = ((((loff_t)page->index) * num_extents_per_page) + extent_num_in_page); + size_t num_header_extents_at_front = + (crypt_stat->num_header_bytes_at_front + / crypt_stat->extent_size); - if (view_extent_num < crypt_stat->num_header_extents_at_front) { + if (view_extent_num < num_header_extents_at_front) { /* This is a header extent */ char *page_virt; @@ -155,9 +159,8 @@ ecryptfs_copy_up_encrypted_with_header(struct page *page, } else { /* This is an encrypted data extent */ loff_t lower_offset = - ((view_extent_num - - crypt_stat->num_header_extents_at_front) - * crypt_stat->extent_size); + ((view_extent_num * crypt_stat->extent_size) + - crypt_stat->num_header_bytes_at_front); rc = ecryptfs_read_lower_page_segment( page, (lower_offset >> PAGE_CACHE_SHIFT), |