eCryptfs: update metadata read/write functions

Update the metadata read/write functions and grow_file() to use the
read_write.c routines.  Do not open another lower file; use the persistent
lower file instead.  Provide a separate function for
crypto.c::ecryptfs_read_xattr_region() to get to the lower xattr without
having to go through the eCryptfs getxattr.

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>

1 files changed, 45 insertions, 56 deletions

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index c746b5d8a336..a29dc31965fa 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -153,37 +153,30 @@ out:
 
 /**
  * grow_file
- * @ecryptfs_dentry: the ecryptfs dentry
- * @lower_file: The lower file
- * @inode: The ecryptfs inode
- * @lower_inode: The lower inode
+ * @ecryptfs_dentry: the eCryptfs dentry
  *
  * This is the code which will grow the file to its correct size.
  */
-static int grow_file(struct dentry *ecryptfs_dentry, struct file *lower_file,
-                     struct inode *inode, struct inode *lower_inode)
+static int grow_file(struct dentry *ecryptfs_dentry)
 {
-        int rc = 0;
+        struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
         struct file fake_file;
         struct ecryptfs_file_info tmp_file_info;
+        char zero_virt[] = { 0x00 };
+        int rc = 0;
 
         memset(&fake_file, 0, sizeof(fake_file));
         fake_file.f_path.dentry = ecryptfs_dentry;
         memset(&tmp_file_info, 0, sizeof(tmp_file_info));
         ecryptfs_set_file_private(&fake_file, &tmp_file_info);
-        ecryptfs_set_file_lower(&fake_file, lower_file);
-        rc = ecryptfs_fill_zeros(&fake_file, 1);
-        if (rc) {
-                ecryptfs_inode_to_private(inode)->crypt_stat.flags |=
-                        ECRYPTFS_SECURITY_WARNING;
-                ecryptfs_printk(KERN_WARNING, "Error attempting to fill zeros "
-                                "in file; rc = [%d]\n", rc);
-                goto out;
-        }
-        i_size_write(inode, 0);
-        rc = ecryptfs_write_inode_size_to_metadata(inode);
-        ecryptfs_inode_to_private(inode)->crypt_stat.flags |= ECRYPTFS_NEW_FILE;
-out:
+        ecryptfs_set_file_lower(
+                &fake_file,
+                ecryptfs_inode_to_private(ecryptfs_inode)->lower_file);
+        rc = ecryptfs_write(&fake_file, zero_virt, 0, 1);
+        i_size_write(ecryptfs_inode, 0);
+        rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
+        ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat.flags |=
+                ECRYPTFS_NEW_FILE;
         return rc;
 }
 
@@ -197,53 +190,31 @@ out:
  */
 static int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry)
 {
+        struct ecryptfs_crypt_stat *crypt_stat =
+                &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
         int rc = 0;
-        int lower_flags;
-        struct ecryptfs_crypt_stat *crypt_stat;
-        struct dentry *lower_dentry;
-        struct file *lower_file;
-        struct inode *inode, *lower_inode;
-        struct vfsmount *lower_mnt;
 
-        lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
-        ecryptfs_printk(KERN_DEBUG, "lower_dentry->d_name.name = [%s]\n",
-                        lower_dentry->d_name.name);
-        inode = ecryptfs_dentry->d_inode;
-        crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
-        lower_flags = ((O_CREAT | O_TRUNC) & O_ACCMODE) | O_RDWR;
-        lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
-        /* Corresponding fput() at end of this function */
-        rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
-                                      lower_flags);
-        if (rc) {
-                ecryptfs_printk(KERN_ERR,
-                                "Error opening dentry; rc = [%i]\n", rc);
-                goto out;
-        }
-        lower_inode = lower_dentry->d_inode;
         if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
                 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
-                goto out_fput;
+                goto out;
         }
         crypt_stat->flags |= ECRYPTFS_NEW_FILE;
         ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
         rc = ecryptfs_new_file_context(ecryptfs_dentry);
         if (rc) {
-                ecryptfs_printk(KERN_DEBUG, "Error creating new file "
-                                "context\n");
-                goto out_fput;
+                ecryptfs_printk(KERN_ERR, "Error creating new file "
+                                "context; rc = [%d]\n", rc);
+                goto out;
         }
-        rc = ecryptfs_write_metadata(ecryptfs_dentry, lower_file);
+        rc = ecryptfs_write_metadata(ecryptfs_dentry);
         if (rc) {
-                ecryptfs_printk(KERN_DEBUG, "Error writing headers\n");
-                goto out_fput;
+                printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
+                goto out;
         }
-        rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode);
-out_fput:
-        rc = ecryptfs_close_lower_file(lower_file);
+        rc = grow_file(ecryptfs_dentry);
         if (rc)
-                printk(KERN_ERR "Error closing lower_file\n");
+                printk(KERN_ERR "Error growing file; rc = [%d]\n", rc);
 out:
         return rc;
 }
@@ -389,8 +360,8 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
         crypt_stat = &ecryptfs_inode_to_private(dentry->d_inode)->crypt_stat;
         if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
                 ecryptfs_set_default_sizes(crypt_stat);
-        rc = ecryptfs_read_and_validate_header_region(page_virt, lower_dentry,
-                                                      nd->mnt);
+        rc = ecryptfs_read_and_validate_header_region(page_virt,
+                                                      dentry->d_inode);
         if (rc) {
                 rc = ecryptfs_read_and_validate_xattr_region(page_virt, dentry);
                 if (rc) {
@@ -941,7 +912,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
                 }
                 mount_crypt_stat = &ecryptfs_superblock_to_private(
                         dentry->d_sb)->mount_crypt_stat;
-                rc = ecryptfs_read_metadata(dentry, lower_file);
+                rc = ecryptfs_read_metadata(dentry);
                 if (rc) {
                         if (!(mount_crypt_stat->flags
                               & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
@@ -1003,6 +974,24 @@ out:
 }
 
 ssize_t
+ecryptfs_getxattr_lower(struct dentry *lower_dentry, const char *name,
+                        void *value, size_t size)
+{
+        int rc = 0;
+
+        if (!lower_dentry->d_inode->i_op->getxattr) {
+                rc = -ENOSYS;
+                goto out;
+        }
+        mutex_lock(&lower_dentry->d_inode->i_mutex);
+        rc = lower_dentry->d_inode->i_op->getxattr(lower_dentry, name, value,
+                                                   size);
+        mutex_unlock(&lower_dentry->d_inode->i_mutex);
+out:
+        return rc;
+}
+
+ssize_t
 ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
                   size_t size)
 {