[PATCH 4/6] eCryptfs: Consolidate lower dentry_open's

Michael Halcrow
2006-10-30T23:37:37Z

Opens on lower dentry objects happen in several places in eCryptfs,
and they all involve the same steps (dget, mntget, dentry_open). This
patch consolidates the lower open events into a single function call.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>

---

fs/ecryptfs/crypto.c | 24 +++++++++++-----------
fs/ecryptfs/ecryptfs_kernel.h | 4 ++++
fs/ecryptfs/file.c | 44 ++++++++++++++++++++++++++++++++++-------
fs/ecryptfs/inode.c | 33 ++++++++++---------------------
4 files changed, 63 insertions(+), 42 deletions(-)

ae8de046956510acf0bd358ac93adccc78f76e84
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index 7f32fcb..3f83613 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1191,28 +1191,28 @@ int ecryptfs_cipher_code_to_string(char
int ecryptfs_read_header_region(char *data, struct dentry *dentry,
struct vfsmount *mnt)
{
- struct file *file;
+ struct file *lower_file;
mm_segment_t oldfs;
int rc;

- mnt = mntget(mnt);
- file = dentry_open(dentry, mnt, O_RDONLY);
- if (IS_ERR(file)) {
- ecryptfs_printk(KERN_DEBUG, "Error opening file to "
- "read header region\n");
- mntput(mnt);
- rc = PTR_ERR(file);
+ if ((rc = ecryptfs_open_lower_file(&lower_file, dentry, mnt,
+ O_RDONLY))) {
+ printk(KERN_ERR
+ "Error opening lower_file to read header region\n");
goto out;
}
- file->f_pos = 0;
+ lower_file->f_pos = 0;
oldfs = get_fs();
set_fs(get_ds());
/* For releases 0.1 and 0.2, all of the header information
* fits in the first data extent-sized region. */
- rc = file->f_op->read(file, (char __user *)data,
- ECRYPTFS_DEFAULT_EXTENT_SIZE, &file->f_pos);
+ rc = lower_file->f_op->read(lower_file, (char __user *)data,
+ ECRYPTFS_DEFAULT_EXTENT_SIZE, &lower_file->f_pos);
set_fs(oldfs);
- fput(file);
+ if ((rc = ecryptfs_close_lower_file(lower_file))) {
+ printk(KERN_ERR "Error closing lower_file\n");
+ goto out;
+ }
rc = 0;
out:
return rc;
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 199fcda..f992533 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -482,5 +482,9 @@ ecryptfs_process_cipher(struct crypto_bl
int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode);
int ecryptfs_inode_set(struct inode *inode, void *lower_inode);
void ecryptfs_init_inode(struct inode *inode, struct inode *lower_inode);
+int ecryptfs_open_lower_file(struct file **lower_file,
+ struct dentry *lower_dentry,
+ struct vfsmount *lower_mnt, int flags);
+int ecryptfs_close_lower_file(struct file *lower_file);

#endif /* #ifndef ECRYPTFS_KERNEL_H */
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index c8550c9..a92ef05 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -198,6 +198,33 @@ retry:

struct kmem_cache *ecryptfs_file_info_cache;

+int ecryptfs_open_lower_file(struct file **lower_file,
+ struct dentry *lower_dentry,
+ struct vfsmount *lower_mnt, int flags)
+{
+ int rc = 0;
+
+ dget(lower_dentry);
+ mntget(lower_mnt);
+ *lower_file = dentry_open(lower_dentry, lower_mnt, flags);
+ if (IS_ERR(*lower_file)) {
+ printk(KERN_ERR "Error opening lower file for lower_dentry "
+ "[0x%p], lower_mnt [0x%p], and flags [0x%x]\n",
+ lower_dentry, lower_mnt, flags);
+ rc = PTR_ERR(*lower_file);
+ *lower_file = NULL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+int ecryptfs_close_lower_file(struct file *lower_file)
+{
+ fput(lower_file);
+ return 0;
+}
+
/**
* ecryptfs_open
* @inode: inode speciying file to open
@@ -244,19 +271,15 @@ static int ecryptfs_open(struct inode *i
ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
}
mutex_unlock(&crypt_stat->cs_mutex);
- /* This mntget & dget is undone via fput when the file is released */
- dget(lower_dentry);
lower_flags = file->f_flags;
if ((lower_flags & O_ACCMODE) == O_WRONLY)
lower_flags = (lower_flags & O_ACCMODE) | O_RDWR;
if (file->f_flags & O_APPEND)
lower_flags &= ~O_APPEND;
lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
- mntget(lower_mnt);
/* Corresponding fput() in ecryptfs_release() */
- lower_file = dentry_open(lower_dentry, lower_mnt, lower_flags);
- if (IS_ERR(lower_file)) {
- rc = PTR_ERR(lower_file);
+ if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
+ lower_flags))) {
ecryptfs_printk(KERN_ERR, "Error opening lower file\n");
goto out_puts;
}
@@ -341,11 +364,16 @@ static int ecryptfs_release(struct inode
struct file *lower_file = ecryptfs_file_to_lower(file);
struct ecryptfs_file_info *file_info = ecryptfs_file_to_private(file);
struct inode *lower_inode = ecryptfs_inode_to_lower(inode);
+ int rc;

- fput(lower_file);
+ if ((rc = ecryptfs_close_lower_file(lower_file))) {
+ printk(KERN_ERR "Error closing lower_file\n");
+ goto out;
+ }
inode->i_blocks = lower_inode->i_blocks;
kmem_cache_free(ecryptfs_file_info_cache, file_info);
- return 0;
+out:
+ return rc;
}

static int
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index efdd2b7..2f2c6cf 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -231,7 +231,6 @@ static int ecryptfs_initialize_file(stru
int lower_flags;
struct ecryptfs_crypt_stat *crypt_stat;
struct dentry *lower_dentry;
- struct dentry *tlower_dentry = NULL;
struct file *lower_file;
struct inode *inode, *lower_inode;
struct vfsmount *lower_mnt;
@@ -241,30 +240,19 @@ static int ecryptfs_initialize_file(stru
lower_dentry->d_name.name);
inode = ecryptfs_dentry->d_inode;
crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
- tlower_dentry = dget(lower_dentry);
- if (!tlower_dentry) {
- rc = -ENOMEM;
- ecryptfs_printk(KERN_ERR, "Error dget'ing lower_dentry\n");
- goto out;
- }
lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR;
#if BITS_PER_LONG != 32
lower_flags |= O_LARGEFILE;
#endif
lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
- mntget(lower_mnt);
/* Corresponding fput() at end of this function */
- lower_file = dentry_open(tlower_dentry, lower_mnt, lower_flags);
- if (IS_ERR(lower_file)) {
- rc = PTR_ERR(lower_file);
+ if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
+ lower_flags))) {
ecryptfs_printk(KERN_ERR,
"Error opening dentry; rc = [%i]\n", rc);
goto out;
}
- /* fput(lower_file) should handle the puts if we do this */
- lower_file->f_dentry = tlower_dentry;
- lower_file->f_vfsmnt = lower_mnt;
- lower_inode = tlower_dentry->d_inode;
+ lower_inode = lower_dentry->d_inode;
if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
@@ -285,7 +273,8 @@ #endif
}
rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode);
out_fput:
- fput(lower_file);
+ if ((rc = ecryptfs_close_lower_file(lower_file)))
+ printk(KERN_ERR "Error closing lower_file\n");
out:
return rc;
}
@@ -832,12 +821,11 @@ int ecryptfs_truncate(struct dentry *den
}
lower_dentry = ecryptfs_dentry_to_lower(dentry);
/* This dget & mntget is released through fput at out_fput: */
- dget(lower_dentry);
lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
- mntget(lower_mnt);
- lower_file = dentry_open(lower_dentry, lower_mnt, O_RDWR);
- if (unlikely(IS_ERR(lower_file))) {
- rc = PTR_ERR(lower_file);
+ if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
+ O_RDWR))) {
+ ecryptfs_printk(KERN_ERR,
+ "Error opening dentry; rc = [%i]\n", rc);
goto out_free;
}
ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file);
@@ -879,7 +867,8 @@ int ecryptfs_truncate(struct dentry *den
= CURRENT_TIME;
mark_inode_dirty_sync(inode);
out_fput:
- fput(lower_file);
+ if ((rc = ecryptfs_close_lower_file(lower_file)))
+ printk(KERN_ERR "Error closing lower_file\n");
out_free:
if (ecryptfs_file_to_private(&fake_ecryptfs_file))
kmem_cache_free(ecryptfs_file_info_cache,
--
1.3.3