mirror of
https://github.com/Fishwaldo/Star64_linux.git
synced 2025-07-07 06:52:07 +00:00
eCryptfs: make open, truncate, and setattr use persistent file
Rather than open a new lower file for every eCryptfs file that is opened, truncated, or setattr'd, instead use the existing lower persistent file for the eCryptfs inode. Change truncate to use read_write.c functions. Change ecryptfs_getxattr() to use the common ecryptfs_getxattr_lower() function. 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>
This commit is contained in:
Michael Halcrow
Linus Torvalds
parent
d7cdc5febf
commit
2ed92554ab
3 changed files with 44 additions and 121 deletions
|
|
@ -739,8 +739,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
|
|||
int rc = 0;
|
||||
struct inode *inode = dentry->d_inode;
|
||||
struct dentry *lower_dentry;
|
||||
struct vfsmount *lower_mnt;
|
||||
struct file fake_ecryptfs_file, *lower_file = NULL;
|
||||
struct file fake_ecryptfs_file;
|
||||
struct ecryptfs_crypt_stat *crypt_stat;
|
||||
loff_t i_size = i_size_read(inode);
|
||||
loff_t lower_size_before_truncate;
|
||||
|
|
@ -763,51 +762,43 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
|
|||
goto out;
|
||||
}
|
||||
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
||||
/* This dget & mntget is released through fput at out_fput: */
|
||||
lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
|
||||
rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
|
||||
O_RDWR);
|
||||
if (rc) {
|
||||
ecryptfs_printk(KERN_ERR,
|
||||
"Error opening dentry; rc = [%i]\n", rc);
|
||||
goto out_free;
|
||||
}
|
||||
ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file);
|
||||
ecryptfs_set_file_lower(
|
||||
&fake_ecryptfs_file,
|
||||
ecryptfs_inode_to_private(dentry->d_inode)->lower_file);
|
||||
/* Switch on growing or shrinking file */
|
||||
if (new_length > i_size) {
|
||||
rc = ecryptfs_fill_zeros(&fake_ecryptfs_file, new_length);
|
||||
if (rc) {
|
||||
ecryptfs_printk(KERN_ERR,
|
||||
"Problem with fill_zeros\n");
|
||||
goto out_fput;
|
||||
}
|
||||
i_size_write(inode, new_length);
|
||||
rc = ecryptfs_write_inode_size_to_metadata(inode);
|
||||
if (rc) {
|
||||
printk(KERN_ERR "Problem with "
|
||||
"ecryptfs_write_inode_size_to_metadata; "
|
||||
"rc = [%d]\n", rc);
|
||||
goto out_fput;
|
||||
}
|
||||
} else { /* new_length < i_size_read(inode) */
|
||||
pgoff_t index = 0;
|
||||
int end_pos_in_page = -1;
|
||||
char zero[] = { 0x00 };
|
||||
|
||||
if (new_length != 0) {
|
||||
index = ((new_length - 1) >> PAGE_CACHE_SHIFT);
|
||||
end_pos_in_page = ((new_length - 1) & ~PAGE_CACHE_MASK);
|
||||
}
|
||||
if (end_pos_in_page != (PAGE_CACHE_SIZE - 1)) {
|
||||
rc = ecryptfs_write_zeros(&fake_ecryptfs_file,
|
||||
index,
|
||||
(end_pos_in_page + 1),
|
||||
((PAGE_CACHE_SIZE - 1)
|
||||
- end_pos_in_page));
|
||||
/* Write a single 0 at the last position of the file;
|
||||
* this triggers code that will fill in 0's throughout
|
||||
* the intermediate portion of the previous end of the
|
||||
* file and the new and of the file */
|
||||
rc = ecryptfs_write(&fake_ecryptfs_file, zero,
|
||||
(new_length - 1), 1);
|
||||
} else { /* new_length < i_size_read(inode) */
|
||||
/* We're chopping off all the pages down do the page
|
||||
* in which new_length is located. Fill in the end of
|
||||
* that page from (new_length & ~PAGE_CACHE_MASK) to
|
||||
* PAGE_CACHE_SIZE with zeros. */
|
||||
size_t num_zeros = (PAGE_CACHE_SIZE
|
||||
- (new_length & ~PAGE_CACHE_MASK));
|
||||
|
||||
if (num_zeros) {
|
||||
char *zeros_virt;
|
||||
|
||||
zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
|
||||
if (!zeros_virt) {
|
||||
rc = -ENOMEM;
|
||||
goto out_free;
|
||||
}
|
||||
rc = ecryptfs_write(&fake_ecryptfs_file, zeros_virt,
|
||||
new_length, num_zeros);
|
||||
kfree(zeros_virt);
|
||||
if (rc) {
|
||||
printk(KERN_ERR "Error attempting to zero out "
|
||||
"the remainder of the end page on "
|
||||
"reducing truncate; rc = [%d]\n", rc);
|
||||
goto out_fput;
|
||||
goto out_free;
|
||||
}
|
||||
}
|
||||
vmtruncate(inode, new_length);
|
||||
|
|
@ -816,7 +807,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
|
|||
printk(KERN_ERR "Problem with "
|
||||
"ecryptfs_write_inode_size_to_metadata; "
|
||||
"rc = [%d]\n", rc);
|
||||
goto out_fput;
|
||||
goto out_free;
|
||||
}
|
||||
/* We are reducing the size of the ecryptfs file, and need to
|
||||
* know if we need to reduce the size of the lower file. */
|
||||
|
|
@ -828,14 +819,6 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
|
|||
vmtruncate(lower_dentry->d_inode,
|
||||
lower_size_after_truncate);
|
||||
}
|
||||
/* Update the access times */
|
||||
lower_dentry->d_inode->i_mtime = lower_dentry->d_inode->i_ctime
|
||||
= CURRENT_TIME;
|
||||
mark_inode_dirty_sync(inode);
|
||||
out_fput:
|
||||
rc = ecryptfs_close_lower_file(lower_file);
|
||||
if (rc)
|
||||
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,
|
||||
|
|
@ -895,21 +878,8 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
|
|||
else if (S_ISREG(dentry->d_inode->i_mode)
|
||||
&& (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
|
||||
|| !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
|
||||
struct vfsmount *lower_mnt;
|
||||
struct file *lower_file = NULL;
|
||||
struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
|
||||
int lower_flags;
|
||||
|
||||
lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
|
||||
lower_flags = O_RDONLY;
|
||||
rc = ecryptfs_open_lower_file(&lower_file, lower_dentry,
|
||||
lower_mnt, lower_flags);
|
||||
if (rc) {
|
||||
printk(KERN_ERR
|
||||
"Error opening lower file; rc = [%d]\n", rc);
|
||||
mutex_unlock(&crypt_stat->cs_mutex);
|
||||
goto out;
|
||||
}
|
||||
mount_crypt_stat = &ecryptfs_superblock_to_private(
|
||||
dentry->d_sb)->mount_crypt_stat;
|
||||
rc = ecryptfs_read_metadata(dentry);
|
||||
|
|
@ -923,16 +893,13 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
|
|||
"enabled; returning -EIO\n");
|
||||
|
||||
mutex_unlock(&crypt_stat->cs_mutex);
|
||||
fput(lower_file);
|
||||
goto out;
|
||||
}
|
||||
rc = 0;
|
||||
crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
|
||||
mutex_unlock(&crypt_stat->cs_mutex);
|
||||
fput(lower_file);
|
||||
goto out;
|
||||
}
|
||||
fput(lower_file);
|
||||
}
|
||||
mutex_unlock(&crypt_stat->cs_mutex);
|
||||
if (ia->ia_valid & ATTR_SIZE) {
|
||||
|
|
@ -995,20 +962,8 @@ ssize_t
|
|||
ecryptfs_getxattr(struct dentry *dentry, const char *name, void *value,
|
||||
size_t size)
|
||||
{
|
||||
int rc = 0;
|
||||
struct dentry *lower_dentry;
|
||||
|
||||
lower_dentry = ecryptfs_dentry_to_lower(dentry);
|
||||
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;
|
||||
return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry), name,
|
||||
value, size);
|
||||
}
|
||||
|
||||
static ssize_t
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue