f2fs crypto: avoid unneeded memory allocation when {en/de}crypting symlink
This patch adopts f2fs with codes of ext4, it removes unneeded memory
allocation in creating/accessing path of symlink.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 6f944e5..fcc8c26 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -345,13 +345,23 @@
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
size_t len = strlen(symname);
- size_t p_len;
- char *p_str;
- struct f2fs_str disk_link = FSTR_INIT(NULL, 0);
+ struct f2fs_str disk_link = FSTR_INIT((char *)symname, len + 1);
struct f2fs_encrypted_symlink_data *sd = NULL;
int err;
- if (len > dir->i_sb->s_blocksize)
+ if (f2fs_encrypted_inode(dir)) {
+ err = f2fs_get_encryption_info(dir);
+ if (err)
+ return err;
+
+ if (!f2fs_encrypted_inode(dir))
+ return -EPERM;
+
+ disk_link.len = (f2fs_fname_encrypted_size(dir, len) +
+ sizeof(struct f2fs_encrypted_symlink_data));
+ }
+
+ if (disk_link.len > dir->i_sb->s_blocksize)
return -ENAMETOOLONG;
inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO);
@@ -374,42 +384,36 @@
f2fs_unlock_op(sbi);
alloc_nid_done(sbi, inode->i_ino);
- if (f2fs_encrypted_inode(dir)) {
+ if (f2fs_encrypted_inode(inode)) {
struct qstr istr = QSTR_INIT(symname, len);
+ struct f2fs_str ostr;
+
+ sd = kzalloc(disk_link.len, GFP_NOFS);
+ if (!sd) {
+ err = -ENOMEM;
+ goto err_out;
+ }
err = f2fs_get_encryption_info(inode);
if (err)
goto err_out;
- err = f2fs_fname_crypto_alloc_buffer(inode, len, &disk_link);
- if (err)
+ if (!f2fs_encrypted_inode(inode)) {
+ err = -EPERM;
goto err_out;
+ }
- err = f2fs_fname_usr_to_disk(inode, &istr, &disk_link);
+ ostr.name = sd->encrypted_path;
+ ostr.len = disk_link.len;
+ err = f2fs_fname_usr_to_disk(inode, &istr, &ostr);
if (err < 0)
goto err_out;
- p_len = encrypted_symlink_data_len(disk_link.len) + 1;
-
- if (p_len > dir->i_sb->s_blocksize) {
- err = -ENAMETOOLONG;
- goto err_out;
- }
-
- sd = kzalloc(p_len, GFP_NOFS);
- if (!sd) {
- err = -ENOMEM;
- goto err_out;
- }
- memcpy(sd->encrypted_path, disk_link.name, disk_link.len);
- sd->len = cpu_to_le16(disk_link.len);
- p_str = (char *)sd;
- } else {
- p_len = len + 1;
- p_str = (char *)symname;
+ sd->len = cpu_to_le16(ostr.len);
+ disk_link.name = (char *)sd;
}
- err = page_symlink(inode, p_str, p_len);
+ err = page_symlink(inode, disk_link.name, disk_link.len);
err_out:
d_instantiate(dentry, inode);
@@ -425,7 +429,8 @@
* performance regression.
*/
if (!err) {
- filemap_write_and_wait_range(inode->i_mapping, 0, p_len - 1);
+ filemap_write_and_wait_range(inode->i_mapping, 0,
+ disk_link.len - 1);
if (IS_DIRSYNC(dir))
f2fs_sync_fs(sbi->sb, 1);
@@ -434,7 +439,6 @@
}
kfree(sd);
- f2fs_fname_crypto_free_buffer(&disk_link);
return err;
out:
handle_failed_inode(inode);
@@ -966,6 +970,7 @@
/* Symlink is encrypted */
sd = (struct f2fs_encrypted_symlink_data *)caddr;
+ cstr.name = sd->encrypted_path;
cstr.len = le16_to_cpu(sd->len);
/* this is broken symlink case */
@@ -973,12 +978,6 @@
res = -ENOENT;
goto errout;
}
- cstr.name = kmalloc(cstr.len, GFP_NOFS);
- if (!cstr.name) {
- res = -ENOMEM;
- goto errout;
- }
- memcpy(cstr.name, sd->encrypted_path, cstr.len);
/* this is broken symlink case */
if (unlikely(cstr.name[0] == 0)) {
@@ -1000,8 +999,6 @@
if (res < 0)
goto errout;
- kfree(cstr.name);
-
paddr = pstr.name;
/* Null-terminate the name */
@@ -1011,7 +1008,6 @@
set_delayed_call(done, kfree_link, paddr);
return paddr;
errout:
- kfree(cstr.name);
f2fs_fname_crypto_free_buffer(&pstr);
page_cache_release(cpage);
return ERR_PTR(res);
