eCryptfs: Remove unused ecryptfs_read()

ecryptfs_read() has been ifdef'ed out for years now and it was
apparently unused before then. It is time to get rid of it for good.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
This commit is contained in:
Tyler Hicks 2012-01-18 15:09:43 -06:00
parent a261a03904
commit f2cb933501

View File

@ -282,76 +282,3 @@ int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
flush_dcache_page(page_for_ecryptfs);
return rc;
}
#if 0
/**
* ecryptfs_read
* @data: The virtual address into which to write the data read (and
* possibly decrypted) from the lower file
* @offset: The offset in the decrypted view of the file from which to
* read into @data
* @size: The number of bytes to read into @data
* @ecryptfs_file: The eCryptfs file from which to read
*
* Read an arbitrary amount of data from an arbitrary location in the
* eCryptfs page cache. This is done on an extent-by-extent basis;
* individual extents are decrypted and read from the lower page
* cache (via VFS reads). This function takes care of all the
* address translation to locations in the lower filesystem.
*
* Returns zero on success; non-zero otherwise
*/
int ecryptfs_read(char *data, loff_t offset, size_t size,
struct file *ecryptfs_file)
{
struct inode *ecryptfs_inode = ecryptfs_file->f_dentry->d_inode;
struct page *ecryptfs_page;
char *ecryptfs_page_virt;
loff_t ecryptfs_file_size = i_size_read(ecryptfs_inode);
loff_t data_offset = 0;
loff_t pos;
int rc = 0;
if ((offset + size) > ecryptfs_file_size) {
rc = -EINVAL;
printk(KERN_ERR "%s: Attempt to read data past the end of the "
"file; offset = [%lld]; size = [%td]; "
"ecryptfs_file_size = [%lld]\n",
__func__, offset, size, ecryptfs_file_size);
goto out;
}
pos = offset;
while (pos < (offset + size)) {
pgoff_t ecryptfs_page_idx = (pos >> PAGE_CACHE_SHIFT);
size_t start_offset_in_page = (pos & ~PAGE_CACHE_MASK);
size_t num_bytes = (PAGE_CACHE_SIZE - start_offset_in_page);
size_t total_remaining_bytes = ((offset + size) - pos);
if (num_bytes > total_remaining_bytes)
num_bytes = total_remaining_bytes;
ecryptfs_page = ecryptfs_get_locked_page(ecryptfs_inode,
ecryptfs_page_idx);
if (IS_ERR(ecryptfs_page)) {
rc = PTR_ERR(ecryptfs_page);
printk(KERN_ERR "%s: Error getting page at "
"index [%ld] from eCryptfs inode "
"mapping; rc = [%d]\n", __func__,
ecryptfs_page_idx, rc);
goto out;
}
ecryptfs_page_virt = kmap_atomic(ecryptfs_page, KM_USER0);
memcpy((data + data_offset),
((char *)ecryptfs_page_virt + start_offset_in_page),
num_bytes);
kunmap_atomic(ecryptfs_page_virt, KM_USER0);
flush_dcache_page(ecryptfs_page);
SetPageUptodate(ecryptfs_page);
unlock_page(ecryptfs_page);
page_cache_release(ecryptfs_page);
pos += num_bytes;
data_offset += num_bytes;
}
out:
return rc;
}
#endif /* 0 */