From 24d15266bd86b7961f309a962fa3aa177a78c49f Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Mon, 15 Apr 2013 17:28:09 -0700 Subject: [PATCH] eCryptfs: Simplify lower file offset calculation Now that lower filesystem IO operations occur for complete PAGE_CACHE_SIZE bytes, the calculation for converting an eCryptfs extent index into a lower file offset can be simplified. Signed-off-by: Tyler Hicks --- fs/ecryptfs/crypto.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 4185584594f5..3547708fb4e1 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -407,15 +407,15 @@ out: } /** - * ecryptfs_lower_offset_for_extent + * lower_offset_for_page * * Convert an eCryptfs page index into a lower byte offset */ -static void ecryptfs_lower_offset_for_extent(loff_t *offset, loff_t extent_num, - struct ecryptfs_crypt_stat *crypt_stat) +static loff_t lower_offset_for_page(struct ecryptfs_crypt_stat *crypt_stat, + struct page *page) { - (*offset) = ecryptfs_lower_header_size(crypt_stat) - + (crypt_stat->extent_size * extent_num); + return ecryptfs_lower_header_size(crypt_stat) + + (page->index << PAGE_CACHE_SHIFT); } /** @@ -517,9 +517,7 @@ int ecryptfs_encrypt_page(struct page *page) } } - ecryptfs_lower_offset_for_extent(&lower_offset, - page->index * (PAGE_CACHE_SIZE / crypt_stat->extent_size), - crypt_stat); + lower_offset = lower_offset_for_page(crypt_stat, page); enc_extent_virt = kmap(enc_extent_page); rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt, lower_offset, PAGE_CACHE_SIZE); @@ -612,9 +610,7 @@ int ecryptfs_decrypt_page(struct page *page) goto out; } - ecryptfs_lower_offset_for_extent(&lower_offset, - page->index * (PAGE_CACHE_SIZE / crypt_stat->extent_size), - crypt_stat); + lower_offset = lower_offset_for_page(crypt_stat, page); enc_extent_virt = kmap(enc_extent_page); rc = ecryptfs_read_lower(enc_extent_virt, lower_offset, PAGE_CACHE_SIZE, ecryptfs_inode);