[PATCH] dm crypt: restructure for workqueue change
Restructure part of the dm-crypt code in preparation for workqueue changes.
Use 'base_bio' or 'clone' variable names consistently throughout. No
functional changes are included in this patch.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index e1e8040..3783cf9 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -30,7 +30,7 @@
*/
struct crypt_io {
struct dm_target *target;
- struct bio *bio;
+ struct bio *base_bio;
struct bio *first_clone;
struct work_struct work;
atomic_t pending;
@@ -319,7 +319,7 @@
crypt_alloc_buffer(struct crypt_config *cc, unsigned int size,
struct bio *base_bio, unsigned int *bio_vec_idx)
{
- struct bio *bio;
+ struct bio *clone;
unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM;
unsigned int i;
@@ -330,23 +330,23 @@
* FIXME: Is this really intelligent?
*/
if (base_bio)
- bio = bio_clone(base_bio, GFP_NOIO|__GFP_NOMEMALLOC);
+ clone = bio_clone(base_bio, GFP_NOIO|__GFP_NOMEMALLOC);
else
- bio = bio_alloc(GFP_NOIO|__GFP_NOMEMALLOC, nr_iovecs);
- if (!bio)
+ clone = bio_alloc(GFP_NOIO|__GFP_NOMEMALLOC, nr_iovecs);
+ if (!clone)
return NULL;
/* if the last bio was not complete, continue where that one ended */
- bio->bi_idx = *bio_vec_idx;
- bio->bi_vcnt = *bio_vec_idx;
- bio->bi_size = 0;
- bio->bi_flags &= ~(1 << BIO_SEG_VALID);
+ clone->bi_idx = *bio_vec_idx;
+ clone->bi_vcnt = *bio_vec_idx;
+ clone->bi_size = 0;
+ clone->bi_flags &= ~(1 << BIO_SEG_VALID);
- /* bio->bi_idx pages have already been allocated */
- size -= bio->bi_idx * PAGE_SIZE;
+ /* clone->bi_idx pages have already been allocated */
+ size -= clone->bi_idx * PAGE_SIZE;
- for(i = bio->bi_idx; i < nr_iovecs; i++) {
- struct bio_vec *bv = bio_iovec_idx(bio, i);
+ for (i = clone->bi_idx; i < nr_iovecs; i++) {
+ struct bio_vec *bv = bio_iovec_idx(clone, i);
bv->bv_page = mempool_alloc(cc->page_pool, gfp_mask);
if (!bv->bv_page)
@@ -357,7 +357,7 @@
* return a partially allocated bio, the caller will then try
* to allocate additional bios while submitting this partial bio
*/
- if ((i - bio->bi_idx) == (MIN_BIO_PAGES - 1))
+ if ((i - clone->bi_idx) == (MIN_BIO_PAGES - 1))
gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT;
bv->bv_offset = 0;
@@ -366,13 +366,13 @@
else
bv->bv_len = size;
- bio->bi_size += bv->bv_len;
- bio->bi_vcnt++;
+ clone->bi_size += bv->bv_len;
+ clone->bi_vcnt++;
size -= bv->bv_len;
}
- if (!bio->bi_size) {
- bio_put(bio);
+ if (!clone->bi_size) {
+ bio_put(clone);
return NULL;
}
@@ -380,13 +380,13 @@
* Remember the last bio_vec allocated to be able
* to correctly continue after the splitting.
*/
- *bio_vec_idx = bio->bi_vcnt;
+ *bio_vec_idx = clone->bi_vcnt;
- return bio;
+ return clone;
}
static void crypt_free_buffer_pages(struct crypt_config *cc,
- struct bio *bio, unsigned int bytes)
+ struct bio *clone, unsigned int bytes)
{
unsigned int i, start, end;
struct bio_vec *bv;
@@ -400,19 +400,19 @@
* A fix to the bi_idx issue in the kernel is in the works, so
* we will hopefully be able to revert to the cleaner solution soon.
*/
- i = bio->bi_vcnt - 1;
- bv = bio_iovec_idx(bio, i);
- end = (i << PAGE_SHIFT) + (bv->bv_offset + bv->bv_len) - bio->bi_size;
+ i = clone->bi_vcnt - 1;
+ bv = bio_iovec_idx(clone, i);
+ end = (i << PAGE_SHIFT) + (bv->bv_offset + bv->bv_len) - clone->bi_size;
start = end - bytes;
start >>= PAGE_SHIFT;
- if (!bio->bi_size)
- end = bio->bi_vcnt;
+ if (!clone->bi_size)
+ end = clone->bi_vcnt;
else
end >>= PAGE_SHIFT;
- for(i = start; i < end; i++) {
- bv = bio_iovec_idx(bio, i);
+ for (i = start; i < end; i++) {
+ bv = bio_iovec_idx(clone, i);
BUG_ON(!bv->bv_page);
mempool_free(bv->bv_page, cc->page_pool);
bv->bv_page = NULL;
@@ -436,7 +436,7 @@
if (io->first_clone)
bio_put(io->first_clone);
- bio_endio(io->bio, io->bio->bi_size, io->error);
+ bio_endio(io->base_bio, io->base_bio->bi_size, io->error);
mempool_free(io, cc->io_pool);
}
@@ -449,20 +449,7 @@
* queued here.
*/
static struct workqueue_struct *_kcryptd_workqueue;
-
-static void kcryptd_do_work(void *data)
-{
- struct crypt_io *io = (struct crypt_io *) data;
- struct crypt_config *cc = (struct crypt_config *) io->target->private;
- struct convert_context ctx;
- int r;
-
- crypt_convert_init(cc, &ctx, io->bio, io->bio,
- io->bio->bi_sector - io->target->begin, 0);
- r = crypt_convert(cc, &ctx);
-
- dec_pending(io, r);
-}
+static void kcryptd_do_work(void *data);
static void kcryptd_queue_io(struct crypt_io *io)
{
@@ -470,6 +457,127 @@
queue_work(_kcryptd_workqueue, &io->work);
}
+static int crypt_endio(struct bio *clone, unsigned int done, int error)
+{
+ struct crypt_io *io = clone->bi_private;
+ struct crypt_config *cc = io->target->private;
+ unsigned read_io = bio_data_dir(clone) == READ;
+
+ /*
+ * free the processed pages, even if
+ * it's only a partially completed write
+ */
+ if (!read_io)
+ crypt_free_buffer_pages(cc, clone, done);
+
+ if (unlikely(clone->bi_size))
+ return 1;
+
+ /*
+ * successful reads are decrypted by the worker thread
+ */
+ if (!read_io)
+ goto out;
+
+ if (unlikely(!bio_flagged(clone, BIO_UPTODATE))) {
+ error = -EIO;
+ goto out;
+ }
+
+ bio_put(clone);
+ kcryptd_queue_io(io);
+ return 0;
+
+out:
+ bio_put(clone);
+ dec_pending(io, error);
+ return error;
+}
+
+static void clone_init(struct crypt_io *io, struct bio *clone)
+{
+ struct crypt_config *cc = io->target->private;
+
+ clone->bi_private = io;
+ clone->bi_end_io = crypt_endio;
+ clone->bi_bdev = cc->dev->bdev;
+ clone->bi_rw = io->base_bio->bi_rw;
+}
+
+static struct bio *clone_read(struct crypt_io *io,
+ sector_t sector)
+{
+ struct crypt_config *cc = io->target->private;
+ struct bio *base_bio = io->base_bio;
+ struct bio *clone;
+
+ /*
+ * The block layer might modify the bvec array, so always
+ * copy the required bvecs because we need the original
+ * one in order to decrypt the whole bio data *afterwards*.
+ */
+ clone = bio_alloc(GFP_NOIO, bio_segments(base_bio));
+ if (unlikely(!clone))
+ return NULL;
+
+ clone_init(io, clone);
+ clone->bi_idx = 0;
+ clone->bi_vcnt = bio_segments(base_bio);
+ clone->bi_size = base_bio->bi_size;
+ memcpy(clone->bi_io_vec, bio_iovec(base_bio),
+ sizeof(struct bio_vec) * clone->bi_vcnt);
+ clone->bi_sector = cc->start + sector;
+
+ return clone;
+}
+
+static struct bio *clone_write(struct crypt_io *io,
+ sector_t sector,
+ unsigned *bvec_idx,
+ struct convert_context *ctx)
+{
+ struct crypt_config *cc = io->target->private;
+ struct bio *base_bio = io->base_bio;
+ struct bio *clone;
+
+ clone = crypt_alloc_buffer(cc, base_bio->bi_size,
+ io->first_clone, bvec_idx);
+ if (!clone)
+ return NULL;
+
+ ctx->bio_out = clone;
+
+ if (unlikely(crypt_convert(cc, ctx) < 0)) {
+ crypt_free_buffer_pages(cc, clone,
+ clone->bi_size);
+ bio_put(clone);
+ return NULL;
+ }
+
+ clone_init(io, clone);
+ clone->bi_sector = cc->start + sector;
+
+ return clone;
+}
+
+static void process_read_endio(struct crypt_io *io)
+{
+ struct crypt_config *cc = io->target->private;
+ struct convert_context ctx;
+
+ crypt_convert_init(cc, &ctx, io->base_bio, io->base_bio,
+ io->base_bio->bi_sector - io->target->begin, 0);
+
+ dec_pending(io, crypt_convert(cc, &ctx));
+}
+
+static void kcryptd_do_work(void *data)
+{
+ struct crypt_io *io = data;
+
+ process_read_endio(io);
+}
+
/*
* Decode key from its hex representation
*/
@@ -481,7 +589,7 @@
buffer[2] = '\0';
- for(i = 0; i < size; i++) {
+ for (i = 0; i < size; i++) {
buffer[0] = *hex++;
buffer[1] = *hex++;
@@ -504,7 +612,7 @@
{
unsigned int i;
- for(i = 0; i < size; i++) {
+ for (i = 0; i < size; i++) {
sprintf(hex, "%02x", *key);
hex += 2;
key++;
@@ -725,88 +833,10 @@
kfree(cc);
}
-static int crypt_endio(struct bio *bio, unsigned int done, int error)
-{
- struct crypt_io *io = (struct crypt_io *) bio->bi_private;
- struct crypt_config *cc = (struct crypt_config *) io->target->private;
-
- if (bio_data_dir(bio) == WRITE) {
- /*
- * free the processed pages, even if
- * it's only a partially completed write
- */
- crypt_free_buffer_pages(cc, bio, done);
- }
-
- if (bio->bi_size)
- return 1;
-
- bio_put(bio);
-
- /*
- * successful reads are decrypted by the worker thread
- */
- if ((bio_data_dir(bio) == READ)
- && bio_flagged(bio, BIO_UPTODATE)) {
- kcryptd_queue_io(io);
- return 0;
- }
-
- dec_pending(io, error);
- return error;
-}
-
-static inline struct bio *
-crypt_clone(struct crypt_config *cc, struct crypt_io *io, struct bio *bio,
- sector_t sector, unsigned int *bvec_idx,
- struct convert_context *ctx)
-{
- struct bio *clone;
-
- if (bio_data_dir(bio) == WRITE) {
- clone = crypt_alloc_buffer(cc, bio->bi_size,
- io->first_clone, bvec_idx);
- if (clone) {
- ctx->bio_out = clone;
- if (crypt_convert(cc, ctx) < 0) {
- crypt_free_buffer_pages(cc, clone,
- clone->bi_size);
- bio_put(clone);
- return NULL;
- }
- }
- } else {
- /*
- * The block layer might modify the bvec array, so always
- * copy the required bvecs because we need the original
- * one in order to decrypt the whole bio data *afterwards*.
- */
- clone = bio_alloc(GFP_NOIO, bio_segments(bio));
- if (clone) {
- clone->bi_idx = 0;
- clone->bi_vcnt = bio_segments(bio);
- clone->bi_size = bio->bi_size;
- memcpy(clone->bi_io_vec, bio_iovec(bio),
- sizeof(struct bio_vec) * clone->bi_vcnt);
- }
- }
-
- if (!clone)
- return NULL;
-
- clone->bi_private = io;
- clone->bi_end_io = crypt_endio;
- clone->bi_bdev = cc->dev->bdev;
- clone->bi_sector = cc->start + sector;
- clone->bi_rw = bio->bi_rw;
-
- return clone;
-}
-
static int crypt_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
- struct crypt_config *cc = (struct crypt_config *) ti->private;
+ struct crypt_config *cc = ti->private;
struct crypt_io *io;
struct convert_context ctx;
struct bio *clone;
@@ -816,7 +846,7 @@
io = mempool_alloc(cc->io_pool, GFP_NOIO);
io->target = ti;
- io->bio = bio;
+ io->base_bio = bio;
io->first_clone = NULL;
io->error = 0;
atomic_set(&io->pending, 1); /* hold a reference */
@@ -829,7 +859,10 @@
* so repeat the whole process until all the data can be handled.
*/
while (remaining) {
- clone = crypt_clone(cc, io, bio, sector, &bvec_idx, &ctx);
+ if (bio_data_dir(bio) == WRITE)
+ clone = clone_write(io, sector, &bvec_idx, &ctx);
+ else
+ clone = clone_read(io, sector);
if (!clone)
goto cleanup;