fscrypt: factor out bio specific functions
That way we can get rid of the direct dependency on CONFIG_BLOCK.
Fixes: d475a507457b ("ubifs: Add skeleton for fscrypto")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index ac8e4f6..02a7a92 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -24,7 +24,6 @@
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/ratelimit.h>
-#include <linux/bio.h>
#include <linux/dcache.h>
#include <linux/namei.h>
#include "fscrypt_private.h"
@@ -44,7 +43,7 @@
static LIST_HEAD(fscrypt_free_ctxs);
static DEFINE_SPINLOCK(fscrypt_ctx_lock);
-static struct workqueue_struct *fscrypt_read_workqueue;
+struct workqueue_struct *fscrypt_read_workqueue;
static DEFINE_MUTEX(fscrypt_init_mutex);
static struct kmem_cache *fscrypt_ctx_cachep;
@@ -141,16 +140,10 @@
complete(&ecr->completion);
}
-typedef enum {
- FS_DECRYPT = 0,
- FS_ENCRYPT,
-} fscrypt_direction_t;
-
-static int do_page_crypto(const struct inode *inode,
- fscrypt_direction_t rw, u64 lblk_num,
- struct page *src_page, struct page *dest_page,
- unsigned int len, unsigned int offs,
- gfp_t gfp_flags)
+int fscrypt_do_page_crypto(const struct inode *inode, fscrypt_direction_t rw,
+ u64 lblk_num, struct page *src_page,
+ struct page *dest_page, unsigned int len,
+ unsigned int offs, gfp_t gfp_flags)
{
struct {
__le64 index;
@@ -205,7 +198,8 @@
return 0;
}
-static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags)
+struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
+ gfp_t gfp_flags)
{
ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, gfp_flags);
if (ctx->w.bounce_page == NULL)
@@ -260,9 +254,9 @@
if (inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES) {
/* with inplace-encryption we just encrypt the page */
- err = do_page_crypto(inode, FS_ENCRYPT, lblk_num,
- page, ciphertext_page,
- len, offs, gfp_flags);
+ err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, page,
+ ciphertext_page, len, offs,
+ gfp_flags);
if (err)
return ERR_PTR(err);
@@ -276,14 +270,14 @@
return (struct page *)ctx;
/* The encryption operation will require a bounce page. */
- ciphertext_page = alloc_bounce_page(ctx, gfp_flags);
+ ciphertext_page = fscrypt_alloc_bounce_page(ctx, gfp_flags);
if (IS_ERR(ciphertext_page))
goto errout;
ctx->w.control_page = page;
- err = do_page_crypto(inode, FS_ENCRYPT, lblk_num,
- page, ciphertext_page,
- len, offs, gfp_flags);
+ err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num,
+ page, ciphertext_page, len, offs,
+ gfp_flags);
if (err) {
ciphertext_page = ERR_PTR(err);
goto errout;
@@ -320,72 +314,11 @@
if (!(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES))
BUG_ON(!PageLocked(page));
- return do_page_crypto(inode, FS_DECRYPT, lblk_num, page, page, len,
- offs, GFP_NOFS);
+ return fscrypt_do_page_crypto(inode, FS_DECRYPT, lblk_num, page, page,
+ len, offs, GFP_NOFS);
}
EXPORT_SYMBOL(fscrypt_decrypt_page);
-int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
- sector_t pblk, unsigned int len)
-{
- struct fscrypt_ctx *ctx;
- struct page *ciphertext_page = NULL;
- struct bio *bio;
- int ret, err = 0;
-
- BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
-
- ctx = fscrypt_get_ctx(inode, GFP_NOFS);
- if (IS_ERR(ctx))
- return PTR_ERR(ctx);
-
- ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT);
- if (IS_ERR(ciphertext_page)) {
- err = PTR_ERR(ciphertext_page);
- goto errout;
- }
-
- while (len--) {
- err = do_page_crypto(inode, FS_ENCRYPT, lblk,
- ZERO_PAGE(0), ciphertext_page,
- PAGE_SIZE, 0, GFP_NOFS);
- if (err)
- goto errout;
-
- bio = bio_alloc(GFP_NOWAIT, 1);
- if (!bio) {
- err = -ENOMEM;
- goto errout;
- }
- bio->bi_bdev = inode->i_sb->s_bdev;
- bio->bi_iter.bi_sector =
- pblk << (inode->i_sb->s_blocksize_bits - 9);
- bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
- ret = bio_add_page(bio, ciphertext_page,
- inode->i_sb->s_blocksize, 0);
- if (ret != inode->i_sb->s_blocksize) {
- /* should never happen! */
- WARN_ON(1);
- bio_put(bio);
- err = -EIO;
- goto errout;
- }
- err = submit_bio_wait(bio);
- if ((err == 0) && bio->bi_error)
- err = -EIO;
- bio_put(bio);
- if (err)
- goto errout;
- lblk++;
- pblk++;
- }
- err = 0;
-errout:
- fscrypt_release_ctx(ctx);
- return err;
-}
-EXPORT_SYMBOL(fscrypt_zeroout_range);
-
/*
* Validate dentries for encrypted directories to make sure we aren't
* potentially caching stale data after a key has been added or
@@ -442,64 +375,6 @@
};
EXPORT_SYMBOL(fscrypt_d_ops);
-/*
- * Call fscrypt_decrypt_page on every single page, reusing the encryption
- * context.
- */
-static void completion_pages(struct work_struct *work)
-{
- struct fscrypt_ctx *ctx =
- container_of(work, struct fscrypt_ctx, r.work);
- struct bio *bio = ctx->r.bio;
- struct bio_vec *bv;
- int i;
-
- bio_for_each_segment_all(bv, bio, i) {
- struct page *page = bv->bv_page;
- int ret = fscrypt_decrypt_page(page->mapping->host, page,
- PAGE_SIZE, 0, page->index);
-
- if (ret) {
- WARN_ON_ONCE(1);
- SetPageError(page);
- } else {
- SetPageUptodate(page);
- }
- unlock_page(page);
- }
- fscrypt_release_ctx(ctx);
- bio_put(bio);
-}
-
-void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
-{
- INIT_WORK(&ctx->r.work, completion_pages);
- ctx->r.bio = bio;
- queue_work(fscrypt_read_workqueue, &ctx->r.work);
-}
-EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
-
-void fscrypt_pullback_bio_page(struct page **page, bool restore)
-{
- struct fscrypt_ctx *ctx;
- struct page *bounce_page;
-
- /* The bounce data pages are unmapped. */
- if ((*page)->mapping)
- return;
-
- /* The bounce data page is unmapped. */
- bounce_page = *page;
- ctx = (struct fscrypt_ctx *)page_private(bounce_page);
-
- /* restore control page */
- *page = ctx->w.control_page;
-
- if (restore)
- fscrypt_restore_control_page(bounce_page);
-}
-EXPORT_SYMBOL(fscrypt_pullback_bio_page);
-
void fscrypt_restore_control_page(struct page *page)
{
struct fscrypt_ctx *ctx;