#include <linux/scatterlist.h>
#include "ecryptfs_kernel.h"
-struct kmem_cache *ecryptfs_lower_page_cache;
-
/**
* ecryptfs_get_locked_page
*
struct ecryptfs_crypt_stat *crypt_stat)
{
size_t written;
- int save_num_header_extents_at_front =
- crypt_stat->num_header_extents_at_front;
+ size_t save_num_header_bytes_at_front =
+ crypt_stat->num_header_bytes_at_front;
- crypt_stat->num_header_extents_at_front = 1;
+ crypt_stat->num_header_bytes_at_front =
+ ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
ecryptfs_write_header_metadata(page_virt + 20, crypt_stat, &written);
- crypt_stat->num_header_extents_at_front =
- save_num_header_extents_at_front;
+ crypt_stat->num_header_bytes_at_front =
+ save_num_header_bytes_at_front;
}
/**
loff_t view_extent_num = ((((loff_t)page->index)
* num_extents_per_page)
+ extent_num_in_page);
+ size_t num_header_extents_at_front =
+ (crypt_stat->num_header_bytes_at_front
+ / crypt_stat->extent_size);
- if (view_extent_num < crypt_stat->num_header_extents_at_front) {
+ if (view_extent_num < num_header_extents_at_front) {
/* This is a header extent */
char *page_virt;
flush_dcache_page(page);
if (rc) {
printk(KERN_ERR "%s: Error reading xattr "
- "region; rc = [%d]\n", __FUNCTION__, rc);
+ "region; rc = [%d]\n", __func__, rc);
goto out;
}
} else {
/* This is an encrypted data extent */
loff_t lower_offset =
- ((view_extent_num -
- crypt_stat->num_header_extents_at_front)
- * crypt_stat->extent_size);
+ ((view_extent_num * crypt_stat->extent_size)
+ - crypt_stat->num_header_bytes_at_front);
rc = ecryptfs_read_lower_page_segment(
page, (lower_offset >> PAGE_CACHE_SHIFT),
if (rc) {
printk(KERN_ERR "%s: Error attempting to read "
"extent at offset [%lld] in the lower "
- "file; rc = [%d]\n", __FUNCTION__,
+ "file; rc = [%d]\n", __func__,
lower_offset, rc);
goto out;
}
"the encrypted content from the lower "
"file whilst inserting the metadata "
"from the xattr into the header; rc = "
- "[%d]\n", __FUNCTION__, rc);
+ "[%d]\n", __func__, rc);
goto out;
}
end_byte_in_page = i_size_read(inode) % PAGE_CACHE_SIZE;
if (to > end_byte_in_page)
end_byte_in_page = to;
- zero_user_page(page, end_byte_in_page,
- PAGE_CACHE_SIZE - end_byte_in_page, KM_USER0);
+ zero_user_segment(page, end_byte_in_page, PAGE_CACHE_SIZE);
out:
return 0;
}
-/* This function must zero any hole we create */
+/**
+ * ecryptfs_prepare_write
+ * @file: The eCryptfs file
+ * @page: The eCryptfs page
+ * @from: The start byte from which we will write
+ * @to: The end byte to which we will write
+ *
+ * This function must zero any hole we create
+ *
+ * Returns zero on success; non-zero otherwise
+ */
static int ecryptfs_prepare_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
- int rc = 0;
loff_t prev_page_end_size;
+ int rc = 0;
if (!PageUptodate(page)) {
- rc = ecryptfs_read_lower_page_segment(page, page->index, 0,
- PAGE_CACHE_SIZE,
- page->mapping->host);
- if (rc) {
- printk(KERN_ERR "%s: Error attemping to read lower "
- "page segment; rc = [%d]\n", __FUNCTION__, rc);
- ClearPageUptodate(page);
- goto out;
- } else
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(
+ file->f_path.dentry->d_inode)->crypt_stat;
+
+ if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)
+ || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) {
+ rc = ecryptfs_read_lower_page_segment(
+ page, page->index, 0, PAGE_CACHE_SIZE,
+ page->mapping->host);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attemping to read "
+ "lower page segment; rc = [%d]\n",
+ __func__, rc);
+ ClearPageUptodate(page);
+ goto out;
+ } else
+ SetPageUptodate(page);
+ } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) {
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
+ rc = ecryptfs_copy_up_encrypted_with_header(
+ page, crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting "
+ "to copy the encrypted content "
+ "from the lower file whilst "
+ "inserting the metadata from "
+ "the xattr into the header; rc "
+ "= [%d]\n", __func__, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+ } else {
+ rc = ecryptfs_read_lower_page_segment(
+ page, page->index, 0, PAGE_CACHE_SIZE,
+ page->mapping->host);
+ if (rc) {
+ printk(KERN_ERR "%s: Error reading "
+ "page; rc = [%d]\n",
+ __func__, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
+ }
+ } else {
+ rc = ecryptfs_decrypt_page(page);
+ if (rc) {
+ printk(KERN_ERR "%s: Error decrypting page "
+ "at index [%ld]; rc = [%d]\n",
+ __func__, page->index, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
SetPageUptodate(page);
+ }
}
-
prev_page_end_size = ((loff_t)page->index << PAGE_CACHE_SHIFT);
-
- /*
- * If creating a page or more of holes, zero them out via truncate.
- * Note, this will increase i_size.
- */
+ /* If creating a page or more of holes, zero them out via truncate.
+ * Note, this will increase i_size. */
if (page->index != 0) {
if (prev_page_end_size > i_size_read(page->mapping->host)) {
rc = ecryptfs_truncate(file->f_path.dentry,
prev_page_end_size);
if (rc) {
- printk(KERN_ERR "Error on attempt to "
+ printk(KERN_ERR "%s: Error on attempt to "
"truncate to (higher) offset [%lld];"
- " rc = [%d]\n", prev_page_end_size, rc);
+ " rc = [%d]\n", __func__,
+ prev_page_end_size, rc);
goto out;
}
}
}
- /*
- * Writing to a new page, and creating a small hole from start of page?
- * Zero it out.
- */
- if ((i_size_read(page->mapping->host) == prev_page_end_size) &&
- (from != 0)) {
- zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
- }
+ /* Writing to a new page, and creating a small hole from start
+ * of page? Zero it out. */
+ if ((i_size_read(page->mapping->host) == prev_page_end_size)
+ && (from != 0))
+ zero_user(page, 0, PAGE_CACHE_SIZE);
out:
return rc;
}
kfree(file_size_virt);
if (rc)
printk(KERN_ERR "%s: Error writing file size to header; "
- "rc = [%d]\n", __FUNCTION__, rc);
+ "rc = [%d]\n", __func__, rc);
out:
return rc;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff