X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fecryptfs%2Fmmap.c;h=05772aeaa8f4ce09a9cf31e446315802c6cc1969;hb=7f09410bbc4306f592cfb43812389ea1c7905a20;hp=82bdbed658d70faba8d93dd7527d38a30b63c6e0;hpb=ae73fc093a8cae4d92e22ab8b635e3590e80785d;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 82bdbed..05772ae 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -32,144 +32,33 @@ #include #include #include +#include #include "ecryptfs_kernel.h" -struct kmem_cache *ecryptfs_lower_page_cache; - /** - * ecryptfs_get1page + * ecryptfs_get_locked_page * * Get one page from cache or lower f/s, return error otherwise. * - * Returns unlocked and up-to-date page (if ok), with increased + * Returns locked and up-to-date page (if ok), with increased * refcnt. */ -static struct page *ecryptfs_get1page(struct file *file, int index) +struct page *ecryptfs_get_locked_page(struct file *file, loff_t index) { - struct page *page; struct dentry *dentry; struct inode *inode; struct address_space *mapping; + struct page *page; dentry = file->f_path.dentry; inode = dentry->d_inode; mapping = inode->i_mapping; - page = read_cache_page(mapping, index, - (filler_t *)mapping->a_ops->readpage, - (void *)file); - if (IS_ERR(page)) - goto out; - wait_on_page_locked(page); -out: + page = read_mapping_page(mapping, index, (void *)file); + if (!IS_ERR(page)) + lock_page(page); return page; } -static -int write_zeros(struct file *file, pgoff_t index, int start, int num_zeros); - -/** - * ecryptfs_fill_zeros - * @file: The ecryptfs file - * @new_length: The new length of the data in the underlying file; - * everything between the prior end of the file and the - * new end of the file will be filled with zero's. - * new_length must be greater than current length - * - * Function for handling lseek-ing past the end of the file. - * - * This function does not support shrinking, only growing a file. - * - * Returns zero on success; non-zero otherwise. - */ -int ecryptfs_fill_zeros(struct file *file, loff_t new_length) -{ - int rc = 0; - struct dentry *dentry = file->f_path.dentry; - struct inode *inode = dentry->d_inode; - pgoff_t old_end_page_index = 0; - pgoff_t index = old_end_page_index; - int old_end_pos_in_page = -1; - pgoff_t new_end_page_index; - int new_end_pos_in_page; - loff_t cur_length = i_size_read(inode); - - if (cur_length != 0) { - index = old_end_page_index = - ((cur_length - 1) >> PAGE_CACHE_SHIFT); - old_end_pos_in_page = ((cur_length - 1) & ~PAGE_CACHE_MASK); - } - new_end_page_index = ((new_length - 1) >> PAGE_CACHE_SHIFT); - new_end_pos_in_page = ((new_length - 1) & ~PAGE_CACHE_MASK); - ecryptfs_printk(KERN_DEBUG, "old_end_page_index = [0x%.16x]; " - "old_end_pos_in_page = [%d]; " - "new_end_page_index = [0x%.16x]; " - "new_end_pos_in_page = [%d]\n", - old_end_page_index, old_end_pos_in_page, - new_end_page_index, new_end_pos_in_page); - if (old_end_page_index == new_end_page_index) { - /* Start and end are in the same page; we just need to - * set a portion of the existing page to zero's */ - rc = write_zeros(file, index, (old_end_pos_in_page + 1), - (new_end_pos_in_page - old_end_pos_in_page)); - if (rc) - ecryptfs_printk(KERN_ERR, "write_zeros(file=[%p], " - "index=[0x%.16x], " - "old_end_pos_in_page=[d], " - "(PAGE_CACHE_SIZE - new_end_pos_in_page" - "=[%d]" - ")=[d]) returned [%d]\n", file, index, - old_end_pos_in_page, - new_end_pos_in_page, - (PAGE_CACHE_SIZE - new_end_pos_in_page), - rc); - goto out; - } - /* Fill the remainder of the previous last page with zeros */ - rc = write_zeros(file, index, (old_end_pos_in_page + 1), - ((PAGE_CACHE_SIZE - 1) - old_end_pos_in_page)); - if (rc) { - ecryptfs_printk(KERN_ERR, "write_zeros(file=[%p], " - "index=[0x%.16x], old_end_pos_in_page=[d], " - "(PAGE_CACHE_SIZE - old_end_pos_in_page)=[d]) " - "returned [%d]\n", file, index, - old_end_pos_in_page, - (PAGE_CACHE_SIZE - old_end_pos_in_page), rc); - goto out; - } - index++; - while (index < new_end_page_index) { - /* Fill all intermediate pages with zeros */ - rc = write_zeros(file, index, 0, PAGE_CACHE_SIZE); - if (rc) { - ecryptfs_printk(KERN_ERR, "write_zeros(file=[%p], " - "index=[0x%.16x], " - "old_end_pos_in_page=[d], " - "(PAGE_CACHE_SIZE - new_end_pos_in_page" - "=[%d]" - ")=[d]) returned [%d]\n", file, index, - old_end_pos_in_page, - new_end_pos_in_page, - (PAGE_CACHE_SIZE - new_end_pos_in_page), - rc); - goto out; - } - index++; - } - /* Fill the portion at the beginning of the last new page with - * zero's */ - rc = write_zeros(file, index, 0, (new_end_pos_in_page + 1)); - if (rc) { - ecryptfs_printk(KERN_ERR, "write_zeros(file=" - "[%p], index=[0x%.16x], 0, " - "new_end_pos_in_page=[%d]" - "returned [%d]\n", file, index, - new_end_pos_in_page, rc); - goto out; - } -out: - return rc; -} - /** * ecryptfs_writepage * @page: Page that is locked before this call is made @@ -178,13 +67,9 @@ out: */ static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc) { - struct ecryptfs_page_crypt_context ctx; int rc; - ctx.page = page; - ctx.mode = ECRYPTFS_WRITEPAGE_MODE; - ctx.param.wbc = wbc; - rc = ecryptfs_encrypt_page(&ctx); + rc = ecryptfs_encrypt_page(page); if (rc) { ecryptfs_printk(KERN_WARNING, "Error encrypting " "page (upper index [0x%.16x])\n", page->index); @@ -198,60 +83,6 @@ out: } /** - * Reads the data from the lower file file at index lower_page_index - * and copies that data into page. - * - * @param page Page to fill - * @param lower_page_index Index of the page in the lower file to get - */ -int ecryptfs_do_readpage(struct file *file, struct page *page, - pgoff_t lower_page_index) -{ - int rc; - struct dentry *dentry; - struct file *lower_file; - struct dentry *lower_dentry; - struct inode *inode; - struct inode *lower_inode; - char *page_data; - struct page *lower_page = NULL; - char *lower_page_data; - const struct address_space_operations *lower_a_ops; - - dentry = file->f_path.dentry; - lower_file = ecryptfs_file_to_lower(file); - lower_dentry = ecryptfs_dentry_to_lower(dentry); - inode = dentry->d_inode; - lower_inode = ecryptfs_inode_to_lower(inode); - lower_a_ops = lower_inode->i_mapping->a_ops; - lower_page = read_cache_page(lower_inode->i_mapping, lower_page_index, - (filler_t *)lower_a_ops->readpage, - (void *)lower_file); - if (IS_ERR(lower_page)) { - rc = PTR_ERR(lower_page); - lower_page = NULL; - ecryptfs_printk(KERN_ERR, "Error reading from page cache\n"); - goto out; - } - wait_on_page_locked(lower_page); - page_data = kmap_atomic(page, KM_USER0); - lower_page_data = kmap_atomic(lower_page, KM_USER1); - memcpy(page_data, lower_page_data, PAGE_CACHE_SIZE); - kunmap_atomic(lower_page_data, KM_USER1); - flush_dcache_page(lower_page); - kunmap_atomic(page_data, KM_USER0); - flush_dcache_page(page); - rc = 0; -out: - if (likely(lower_page)) - page_cache_release(lower_page); - if (rc == 0) - SetPageUptodate(page); - else - ClearPageUptodate(page); - return rc; -} -/** * Header Extent: * Octets 0-7: Unencrypted file size (big-endian) * Octets 8-15: eCryptfs special marker @@ -270,19 +101,90 @@ static void set_header_info(char *page_virt, 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; +} + +/** + * ecryptfs_copy_up_encrypted_with_header + * @page: Sort of a ``virtual'' representation of the encrypted lower + * file. The actual lower file does not have the metadata in + * the header. This is locked. + * @crypt_stat: The eCryptfs inode's cryptographic context + * + * The ``view'' is the version of the file that userspace winds up + * seeing, with the header information inserted. + */ +static int +ecryptfs_copy_up_encrypted_with_header(struct page *page, + struct ecryptfs_crypt_stat *crypt_stat) +{ + loff_t extent_num_in_page = 0; + loff_t num_extents_per_page = (PAGE_CACHE_SIZE + / crypt_stat->extent_size); + int rc = 0; + + while (extent_num_in_page < num_extents_per_page) { + 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 < num_header_extents_at_front) { + /* This is a header extent */ + char *page_virt; + + page_virt = kmap_atomic(page, KM_USER0); + memset(page_virt, 0, PAGE_CACHE_SIZE); + /* TODO: Support more than one header extent */ + if (view_extent_num == 0) { + rc = ecryptfs_read_xattr_region( + page_virt, page->mapping->host); + set_header_info(page_virt, crypt_stat); + } + kunmap_atomic(page_virt, KM_USER0); + flush_dcache_page(page); + if (rc) { + printk(KERN_ERR "%s: Error reading xattr " + "region; rc = [%d]\n", __func__, rc); + goto out; + } + } else { + /* This is an encrypted data extent */ + loff_t lower_offset = + ((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), + (lower_offset & ~PAGE_CACHE_MASK), + crypt_stat->extent_size, page->mapping->host); + if (rc) { + printk(KERN_ERR "%s: Error attempting to read " + "extent at offset [%lld] in the lower " + "file; rc = [%d]\n", __func__, + lower_offset, rc); + goto out; + } + } + extent_num_in_page++; + } +out: + return rc; } /** * ecryptfs_readpage - * @file: This is an ecryptfs file - * @page: ecryptfs associated page to stick the read data into + * @file: An eCryptfs file + * @page: Page from eCryptfs inode mapping into which to stick the read data * * Read in a page, decrypting if necessary. * @@ -290,59 +192,35 @@ static void set_header_info(char *page_virt, */ static int ecryptfs_readpage(struct file *file, struct page *page) { + struct ecryptfs_crypt_stat *crypt_stat = + &ecryptfs_inode_to_private(file->f_path.dentry->d_inode)->crypt_stat; int rc = 0; - struct ecryptfs_crypt_stat *crypt_stat; - BUG_ON(!(file && file->f_path.dentry && file->f_path.dentry->d_inode)); - crypt_stat = &ecryptfs_inode_to_private(file->f_path.dentry->d_inode) - ->crypt_stat; if (!crypt_stat || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED) || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) { ecryptfs_printk(KERN_DEBUG, "Passing through unencrypted page\n"); - rc = ecryptfs_do_readpage(file, page, page->index); - if (rc) { - ecryptfs_printk(KERN_ERR, "Error reading page; rc = " - "[%d]\n", rc); - goto out; - } + rc = ecryptfs_read_lower_page_segment(page, page->index, 0, + PAGE_CACHE_SIZE, + page->mapping->host); } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) { if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { - int num_pages_in_header_region = - (crypt_stat->header_extent_size - / PAGE_CACHE_SIZE); - - if (page->index < num_pages_in_header_region) { - char *page_virt; - - page_virt = kmap_atomic(page, KM_USER0); - memset(page_virt, 0, PAGE_CACHE_SIZE); - if (page->index == 0) { - rc = ecryptfs_read_xattr_region( - page_virt, file->f_path.dentry); - set_header_info(page_virt, crypt_stat); - } - kunmap_atomic(page_virt, KM_USER0); - flush_dcache_page(page); - if (rc) { - printk(KERN_ERR "Error reading xattr " - "region\n"); - goto out; - } - } else { - rc = ecryptfs_do_readpage( - file, page, - (page->index - - num_pages_in_header_region)); - if (rc) { - printk(KERN_ERR "Error reading page; " - "rc = [%d]\n", rc); - goto out; - } + 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); + goto out; } + } else { - rc = ecryptfs_do_readpage(file, page, page->index); + rc = ecryptfs_read_lower_page_segment( + page, page->index, 0, PAGE_CACHE_SIZE, + page->mapping->host); if (rc) { printk(KERN_ERR "Error reading page; rc = " "[%d]\n", rc); @@ -350,17 +228,18 @@ static int ecryptfs_readpage(struct file *file, struct page *page) } } } else { - rc = ecryptfs_decrypt_page(file, page); + rc = ecryptfs_decrypt_page(page); if (rc) { ecryptfs_printk(KERN_ERR, "Error decrypting page; " "rc = [%d]\n", rc); goto out; } } - SetPageUptodate(page); out: if (rc) ClearPageUptodate(page); + else + SetPageUptodate(page); ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16x]\n", page->index); unlock_page(page); @@ -374,62 +253,128 @@ static int fill_zeros_to_end_of_page(struct page *page, unsigned int to) { struct inode *inode = page->mapping->host; int end_byte_in_page; - char *page_virt; if ((i_size_read(inode) / PAGE_CACHE_SIZE) != page->index) goto out; end_byte_in_page = i_size_read(inode) % PAGE_CACHE_SIZE; if (to > end_byte_in_page) end_byte_in_page = to; - page_virt = kmap_atomic(page, KM_USER0); - memset((page_virt + end_byte_in_page), 0, - (PAGE_CACHE_SIZE - end_byte_in_page)); - kunmap_atomic(page_virt, KM_USER0); - flush_dcache_page(page); + zero_user_segment(page, end_byte_in_page, PAGE_CACHE_SIZE); out: return 0; } -static int ecryptfs_prepare_write(struct file *file, struct page *page, - unsigned from, unsigned to) +/** + * ecryptfs_write_begin + * @file: The eCryptfs file + * @mapping: The eCryptfs object + * @pos: The file offset at which to start writing + * @len: Length of the write + * @flags: Various flags + * @pagep: Pointer to return the page + * @fsdata: Pointer to return fs data (unused) + * + * This function must zero any hole we create + * + * Returns zero on success; non-zero otherwise + */ +static int ecryptfs_write_begin(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) { + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + struct page *page; + loff_t prev_page_end_size; int rc = 0; - if (from == 0 && to == PAGE_CACHE_SIZE) - goto out; /* If we are writing a full page, it will be - up to date. */ - if (!PageUptodate(page)) - rc = ecryptfs_do_readpage(file, page, page->index); -out: - return rc; -} + page = grab_cache_page_write_begin(mapping, index, flags); + if (!page) + return -ENOMEM; + *pagep = page; -int ecryptfs_writepage_and_release_lower_page(struct page *lower_page, - struct inode *lower_inode, - struct writeback_control *wbc) -{ - int rc = 0; + if (!PageUptodate(page)) { + struct ecryptfs_crypt_stat *crypt_stat = + &ecryptfs_inode_to_private( + file->f_path.dentry->d_inode)->crypt_stat; - rc = lower_inode->i_mapping->a_ops->writepage(lower_page, wbc); - if (rc) { - ecryptfs_printk(KERN_ERR, "Error calling lower writepage(); " - "rc = [%d]\n", rc); - goto out; + if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED) + || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) { + rc = ecryptfs_read_lower_page_segment( + page, index, 0, PAGE_CACHE_SIZE, 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, index, 0, PAGE_CACHE_SIZE, + 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)index << PAGE_CACHE_SHIFT); + /* If creating a page or more of holes, zero them out via truncate. + * Note, this will increase i_size. */ + if (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 "%s: Error on attempt to " + "truncate to (higher) offset [%lld];" + " rc = [%d]\n", __func__, + prev_page_end_size, rc); + goto out; + } + } } - lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME; - page_cache_release(lower_page); + /* Writing to a new page, and creating a small hole from start + * of page? Zero it out. */ + if ((i_size_read(mapping->host) == prev_page_end_size) + && (pos != 0)) + zero_user(page, 0, PAGE_CACHE_SIZE); out: return rc; } -static -void ecryptfs_release_lower_page(struct page *lower_page, int page_locked) -{ - if (page_locked) - unlock_page(lower_page); - page_cache_release(lower_page); -} - /** * ecryptfs_write_inode_size_to_header * @@ -437,64 +382,44 @@ void ecryptfs_release_lower_page(struct page *lower_page, int page_locked) * * Returns zero on success; non-zero on error. */ -static int ecryptfs_write_inode_size_to_header(struct file *lower_file, - struct inode *lower_inode, - struct inode *inode) +static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode) { - int rc = 0; - struct page *header_page; - char *header_virt; - const struct address_space_operations *lower_a_ops; - u64 file_size; - - header_page = grab_cache_page(lower_inode->i_mapping, 0); - if (!header_page) { - ecryptfs_printk(KERN_ERR, "grab_cache_page for " - "lower_page_index 0 failed\n"); - rc = -EINVAL; - goto out; - } - lower_a_ops = lower_inode->i_mapping->a_ops; - rc = lower_a_ops->prepare_write(lower_file, header_page, 0, 8); - if (rc) { - if (rc == AOP_TRUNCATED_PAGE) - ecryptfs_release_lower_page(header_page, 0); - else - ecryptfs_release_lower_page(header_page, 1); + char *file_size_virt; + int rc; + + file_size_virt = kmalloc(sizeof(u64), GFP_KERNEL); + if (!file_size_virt) { + rc = -ENOMEM; goto out; } - file_size = (u64)i_size_read(inode); - ecryptfs_printk(KERN_DEBUG, "Writing size: [0x%.16x]\n", file_size); - file_size = cpu_to_be64(file_size); - header_virt = kmap_atomic(header_page, KM_USER0); - memcpy(header_virt, &file_size, sizeof(u64)); - kunmap_atomic(header_virt, KM_USER0); - flush_dcache_page(header_page); - rc = lower_a_ops->commit_write(lower_file, header_page, 0, 8); - if (rc < 0) - ecryptfs_printk(KERN_ERR, "Error commiting header page " - "write\n"); - if (rc == AOP_TRUNCATED_PAGE) - ecryptfs_release_lower_page(header_page, 0); - else - ecryptfs_release_lower_page(header_page, 1); - lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME; - mark_inode_dirty_sync(inode); + put_unaligned_be64(i_size_read(ecryptfs_inode), file_size_virt); + rc = ecryptfs_write_lower(ecryptfs_inode, file_size_virt, 0, + sizeof(u64)); + kfree(file_size_virt); + if (rc) + printk(KERN_ERR "%s: Error writing file size to header; " + "rc = [%d]\n", __func__, rc); out: return rc; } -static int ecryptfs_write_inode_size_to_xattr(struct inode *lower_inode, - struct inode *inode, - struct dentry *ecryptfs_dentry, - int lower_i_mutex_held) +struct kmem_cache *ecryptfs_xattr_cache; + +static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode) { ssize_t size; void *xattr_virt; - struct dentry *lower_dentry; - u64 file_size; + struct dentry *lower_dentry = + ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_dentry; + struct inode *lower_inode = lower_dentry->d_inode; int rc; + if (!lower_inode->i_op->getxattr || !lower_inode->i_op->setxattr) { + printk(KERN_WARNING + "No support for setting xattr in lower filesystem\n"); + rc = -ENOSYS; + goto out; + } xattr_virt = kmem_cache_alloc(ecryptfs_xattr_cache, GFP_KERNEL); if (!xattr_virt) { printk(KERN_ERR "Out of memory whilst attempting to write " @@ -502,34 +427,15 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *lower_inode, rc = -ENOMEM; goto out; } - lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry); - if (!lower_dentry->d_inode->i_op->getxattr) { - printk(KERN_WARNING - "No support for setting xattr in lower filesystem\n"); - rc = -ENOSYS; - kmem_cache_free(ecryptfs_xattr_cache, xattr_virt); - goto out; - } - if (!lower_i_mutex_held) - mutex_lock(&lower_dentry->d_inode->i_mutex); - size = lower_dentry->d_inode->i_op->getxattr(lower_dentry, - ECRYPTFS_XATTR_NAME, - xattr_virt, - PAGE_CACHE_SIZE); - if (!lower_i_mutex_held) - mutex_unlock(&lower_dentry->d_inode->i_mutex); + mutex_lock(&lower_inode->i_mutex); + size = lower_inode->i_op->getxattr(lower_dentry, ECRYPTFS_XATTR_NAME, + xattr_virt, PAGE_CACHE_SIZE); if (size < 0) size = 8; - file_size = (u64)i_size_read(inode); - file_size = cpu_to_be64(file_size); - memcpy(xattr_virt, &file_size, sizeof(u64)); - if (!lower_i_mutex_held) - mutex_lock(&lower_dentry->d_inode->i_mutex); - rc = lower_dentry->d_inode->i_op->setxattr(lower_dentry, - ECRYPTFS_XATTR_NAME, - xattr_virt, size, 0); - if (!lower_i_mutex_held) - mutex_unlock(&lower_dentry->d_inode->i_mutex); + put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt); + rc = lower_inode->i_op->setxattr(lower_dentry, ECRYPTFS_XATTR_NAME, + xattr_virt, size, 0); + mutex_unlock(&lower_inode->i_mutex); if (rc) printk(KERN_ERR "Error whilst attempting to write inode size " "to lower file xattr; rc = [%d]\n", rc); @@ -538,148 +444,45 @@ out: return rc; } -int -ecryptfs_write_inode_size_to_metadata(struct file *lower_file, - struct inode *lower_inode, - struct inode *inode, - struct dentry *ecryptfs_dentry, - int lower_i_mutex_held) +int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode) { struct ecryptfs_crypt_stat *crypt_stat; - crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat; + crypt_stat = &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat; + BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) - return ecryptfs_write_inode_size_to_xattr(lower_inode, inode, - ecryptfs_dentry, - lower_i_mutex_held); + return ecryptfs_write_inode_size_to_xattr(ecryptfs_inode); else - return ecryptfs_write_inode_size_to_header(lower_file, - lower_inode, - inode); -} - -int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode, - struct file *lower_file, - unsigned long lower_page_index, int byte_offset, - int region_bytes) -{ - int rc = 0; - - *lower_page = grab_cache_page(lower_inode->i_mapping, lower_page_index); - if (!(*lower_page)) { - rc = -EINVAL; - ecryptfs_printk(KERN_ERR, "Error attempting to grab " - "lower page with index [0x%.16x]\n", - lower_page_index); - goto out; - } - rc = lower_inode->i_mapping->a_ops->prepare_write(lower_file, - (*lower_page), - byte_offset, - region_bytes); - if (rc) { - ecryptfs_printk(KERN_ERR, "prepare_write for " - "lower_page_index = [0x%.16x] failed; rc = " - "[%d]\n", lower_page_index, rc); - } -out: - if (rc && (*lower_page)) { - if (rc == AOP_TRUNCATED_PAGE) - ecryptfs_release_lower_page(*lower_page, 0); - else - ecryptfs_release_lower_page(*lower_page, 1); - (*lower_page) = NULL; - } - return rc; + return ecryptfs_write_inode_size_to_header(ecryptfs_inode); } /** - * ecryptfs_commit_lower_page - * - * Returns zero on success; non-zero on error - */ -int -ecryptfs_commit_lower_page(struct page *lower_page, struct inode *lower_inode, - struct file *lower_file, int byte_offset, - int region_size) -{ - int page_locked = 1; - int rc = 0; - - rc = lower_inode->i_mapping->a_ops->commit_write( - lower_file, lower_page, byte_offset, region_size); - if (rc == AOP_TRUNCATED_PAGE) - page_locked = 0; - if (rc < 0) { - ecryptfs_printk(KERN_ERR, - "Error committing write; rc = [%d]\n", rc); - } else - rc = 0; - ecryptfs_release_lower_page(lower_page, page_locked); - return rc; -} - -/** - * ecryptfs_copy_page_to_lower - * - * Used for plaintext pass-through; no page index interpolation - * required. - */ -int ecryptfs_copy_page_to_lower(struct page *page, struct inode *lower_inode, - struct file *lower_file) -{ - int rc = 0; - struct page *lower_page; - - rc = ecryptfs_get_lower_page(&lower_page, lower_inode, lower_file, - page->index, 0, PAGE_CACHE_SIZE); - if (rc) { - ecryptfs_printk(KERN_ERR, "Error attempting to get page " - "at index [0x%.16x]\n", page->index); - goto out; - } - /* TODO: aops */ - memcpy((char *)page_address(lower_page), page_address(page), - PAGE_CACHE_SIZE); - rc = ecryptfs_commit_lower_page(lower_page, lower_inode, lower_file, - 0, PAGE_CACHE_SIZE); - if (rc) - ecryptfs_printk(KERN_ERR, "Error attempting to commit page " - "at index [0x%.16x]\n", page->index); -out: - return rc; -} - -struct kmem_cache *ecryptfs_xattr_cache; - -/** - * ecryptfs_commit_write + * ecryptfs_write_end * @file: The eCryptfs file object + * @mapping: The eCryptfs object + * @pos: The file position + * @len: The length of the data (unused) + * @copied: The amount of data copied * @page: The eCryptfs page - * @from: Ignored (we rotate the page IV on each write) - * @to: Ignored + * @fsdata: The fsdata (unused) * * This is where we encrypt the data and pass the encrypted data to * the lower filesystem. In OpenPGP-compatible mode, we operate on * entire underlying packets. */ -static int ecryptfs_commit_write(struct file *file, struct page *page, - unsigned from, unsigned to) +static int ecryptfs_write_end(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned copied, + struct page *page, void *fsdata) { - struct ecryptfs_page_crypt_context ctx; - loff_t pos; - struct inode *inode; - struct inode *lower_inode; - struct file *lower_file; - struct ecryptfs_crypt_stat *crypt_stat; + pgoff_t index = pos >> PAGE_CACHE_SHIFT; + unsigned from = pos & (PAGE_CACHE_SIZE - 1); + unsigned to = from + copied; + struct inode *ecryptfs_inode = mapping->host; + struct ecryptfs_crypt_stat *crypt_stat = + &ecryptfs_inode_to_private(file->f_path.dentry->d_inode)->crypt_stat; int rc; - inode = page->mapping->host; - lower_inode = ecryptfs_inode_to_lower(inode); - lower_file = ecryptfs_file_to_lower(file); - mutex_lock(&lower_inode->i_mutex); - crypt_stat = &ecryptfs_inode_to_private(file->f_path.dentry->d_inode) - ->crypt_stat; if (crypt_stat->flags & ECRYPTFS_NEW_FILE) { ecryptfs_printk(KERN_DEBUG, "ECRYPTFS_NEW_FILE flag set in " "crypt_stat at memory location [%p]\n", crypt_stat); @@ -687,96 +490,44 @@ static int ecryptfs_commit_write(struct file *file, struct page *page, } else ecryptfs_printk(KERN_DEBUG, "Not a new file\n"); ecryptfs_printk(KERN_DEBUG, "Calling fill_zeros_to_end_of_page" - "(page w/ index = [0x%.16x], to = [%d])\n", page->index, - to); + "(page w/ index = [0x%.16x], to = [%d])\n", index, to); + if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) { + rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page, 0, + to); + if (!rc) { + rc = copied; + fsstack_copy_inode_size(ecryptfs_inode, + ecryptfs_inode_to_lower(ecryptfs_inode)); + } + goto out; + } + /* Fills in zeros if 'to' goes beyond inode size */ rc = fill_zeros_to_end_of_page(page, to); if (rc) { ecryptfs_printk(KERN_WARNING, "Error attempting to fill " - "zeros in page with index = [0x%.16x]\n", - page->index); + "zeros in page with index = [0x%.16x]\n", index); goto out; } - ctx.page = page; - ctx.mode = ECRYPTFS_PREPARE_COMMIT_MODE; - ctx.param.lower_file = lower_file; - rc = ecryptfs_encrypt_page(&ctx); + rc = ecryptfs_encrypt_page(page); if (rc) { ecryptfs_printk(KERN_WARNING, "Error encrypting page (upper " - "index [0x%.16x])\n", page->index); + "index [0x%.16x])\n", index); goto out; } - inode->i_blocks = lower_inode->i_blocks; - pos = (page->index << PAGE_CACHE_SHIFT) + to; - if (pos > i_size_read(inode)) { - i_size_write(inode, pos); + if (pos + copied > i_size_read(ecryptfs_inode)) { + i_size_write(ecryptfs_inode, pos + copied); ecryptfs_printk(KERN_DEBUG, "Expanded file size to " - "[0x%.16x]\n", i_size_read(inode)); + "[0x%.16x]\n", i_size_read(ecryptfs_inode)); } - rc = ecryptfs_write_inode_size_to_metadata(lower_file, lower_inode, - inode, file->f_dentry, - ECRYPTFS_LOWER_I_MUTEX_HELD); + rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode); if (rc) printk(KERN_ERR "Error writing inode size to metadata; " "rc = [%d]\n", rc); - lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME; - mark_inode_dirty_sync(inode); -out: - if (rc < 0) - ClearPageUptodate(page); else - SetPageUptodate(page); - mutex_unlock(&lower_inode->i_mutex); - return rc; -} - -/** - * write_zeros - * @file: The ecryptfs file - * @index: The index in which we are writing - * @start: The position after the last block of data - * @num_zeros: The number of zeros to write - * - * Write a specified number of zero's to a page. - * - * (start + num_zeros) must be less than or equal to PAGE_CACHE_SIZE - */ -static -int write_zeros(struct file *file, pgoff_t index, int start, int num_zeros) -{ - int rc = 0; - struct page *tmp_page; - char *tmp_page_virt; - - tmp_page = ecryptfs_get1page(file, index); - if (IS_ERR(tmp_page)) { - ecryptfs_printk(KERN_ERR, "Error getting page at index " - "[0x%.16x]\n", index); - rc = PTR_ERR(tmp_page); - goto out; - } - rc = ecryptfs_prepare_write(file, tmp_page, start, start + num_zeros); - if (rc) { - ecryptfs_printk(KERN_ERR, "Error preparing to write zero's " - "to remainder of page at index [0x%.16x]\n", - index); - page_cache_release(tmp_page); - goto out; - } - tmp_page_virt = kmap_atomic(tmp_page, KM_USER0); - memset(((char *)tmp_page_virt + start), 0, num_zeros); - kunmap_atomic(tmp_page_virt, KM_USER0); - flush_dcache_page(tmp_page); - rc = ecryptfs_commit_write(file, tmp_page, start, start + num_zeros); - if (rc < 0) { - ecryptfs_printk(KERN_ERR, "Error attempting to write zero's " - "to remainder of page at index [0x%.16x]\n", - index); - page_cache_release(tmp_page); - goto out; - } - rc = 0; - page_cache_release(tmp_page); + rc = copied; out: + unlock_page(page); + page_cache_release(page); return rc; } @@ -794,33 +545,10 @@ static sector_t ecryptfs_bmap(struct address_space *mapping, sector_t block) return rc; } -static void ecryptfs_sync_page(struct page *page) -{ - struct inode *inode; - struct inode *lower_inode; - struct page *lower_page; - - inode = page->mapping->host; - lower_inode = ecryptfs_inode_to_lower(inode); - /* NOTE: Recently swapped with grab_cache_page(), since - * sync_page() just makes sure that pending I/O gets done. */ - lower_page = find_lock_page(lower_inode->i_mapping, page->index); - if (!lower_page) { - ecryptfs_printk(KERN_DEBUG, "find_lock_page failed\n"); - return; - } - lower_page->mapping->a_ops->sync_page(lower_page); - ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16x]\n", - lower_page->index); - unlock_page(lower_page); - page_cache_release(lower_page); -} - -struct address_space_operations ecryptfs_aops = { +const struct address_space_operations ecryptfs_aops = { .writepage = ecryptfs_writepage, .readpage = ecryptfs_readpage, - .prepare_write = ecryptfs_prepare_write, - .commit_write = ecryptfs_commit_write, + .write_begin = ecryptfs_write_begin, + .write_end = ecryptfs_write_end, .bmap = ecryptfs_bmap, - .sync_page = ecryptfs_sync_page, };