ext4: provide ext4_issue_zeroout()

Create new function ext4_issue_zeroout() to zeroout contiguous (both
logically and physically) part of inode data. We will need to issue
zeroout when extent structure is not readily available and this function
will allow us to do it without making up fake extent structures.

Change-Id: I5deb04b49d3ebdd1ac12f8bb950faf46d08f5d80
Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Git-commit: 53085fac02d12fcd29a9cb074ec480ff0f77ae5c
Git-repo: https://source.codeaurora.org/quic/la/kernel/msm-4.4
[srkupp@codeaurora.org: Resolved minor conflict]
Signed-off-by: Srinivasa Rao Kuppala <srkupp@codeaurora.org>

4 files changed, 23 insertions, 15 deletions

diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index b9f838af5a72..f5099a3386ec 100644
--- a/fs/ext4/crypto.c
+++ b/fs/ext4/crypto.c
@@ -389,14 +389,12 @@ int ext4_decrypt(struct page *page)
 				page->index, page, page, GFP_NOFS);
 }
 
-int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
+int ext4_encrypted_zeroout(struct inode *inode, ext4_lblk_t lblk,
+			   ext4_fsblk_t pblk, ext4_lblk_t len)
 {
 	struct ext4_crypto_ctx	*ctx;
 	struct page		*ciphertext_page = NULL;
 	struct bio		*bio;
-	ext4_lblk_t		lblk = le32_to_cpu(ex->ee_block);
-	ext4_fsblk_t		pblk = ext4_ext_pblock(ex);
-	unsigned int		len = ext4_ext_get_actual_len(ex);
 	int			ret, err = 0;
 
 #if 0
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 6c910f127f1f..abc9e169cb44 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2271,7 +2271,8 @@ struct page *ext4_encrypt(struct inode *inode,
 			  struct page *plaintext_page,
 			  gfp_t gfp_flags);
 int ext4_decrypt(struct page *page);
-int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);
+int ext4_encrypted_zeroout(struct inode *inode, ext4_lblk_t lblk,
+			   ext4_fsblk_t pblk, ext4_lblk_t len);
 extern const struct dentry_operations ext4_encrypted_d_ops;
 
 #ifdef CONFIG_EXT4_FS_ENCRYPTION
@@ -2539,6 +2540,8 @@ extern int ext4_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
 extern qsize_t *ext4_get_reserved_space(struct inode *inode);
 extern void ext4_da_update_reserve_space(struct inode *inode,
 					int used, int quota_claim);
+extern int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk,
+			      ext4_fsblk_t pblk, ext4_lblk_t len);
 
 /* indirect.c */
 extern int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 61d5bfc7318c..fc496c646d12 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3127,19 +3127,11 @@ static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
 {
 	ext4_fsblk_t ee_pblock;
 	unsigned int ee_len;
-	int ret;
 
 	ee_len    = ext4_ext_get_actual_len(ex);
 	ee_pblock = ext4_ext_pblock(ex);
-
-	if (ext4_encrypted_inode(inode))
-		return ext4_encrypted_zeroout(inode, ex);
-
-	ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
-	if (ret > 0)
-		ret = 0;
-
-	return ret;
+	return ext4_issue_zeroout(inode, le32_to_cpu(ex->ee_block), ee_pblock,
+				  ee_len);
 }
 
 /*
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 46d30bc18c0d..c1d7b3ab8b43 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -390,6 +390,21 @@ static int __check_block_validity(struct inode *inode, const char *func,
 	return 0;
 }
 
+int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
+		       ext4_lblk_t len)
+{
+	int ret;
+
+	if (ext4_encrypted_inode(inode))
+		return ext4_encrypted_zeroout(inode, lblk, pblk, len);
+
+	ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
+	if (ret > 0)
+		ret = 0;
+
+	return ret;
+}
+
 #define check_block_validity(inode, map)	\
 	__check_block_validity((inode), __func__, __LINE__, (map))