#include <asm/page.h>
#include <asm/unaligned.h>
-#include "dm.h"
+#include <linux/device-mapper.h>
#define DM_MSG_PREFIX "crypt"
#define MESG_STR(x) x, sizeof(x)
atomic_t pending;
int error;
sector_t sector;
+ struct dm_crypt_io *base_io;
};
struct dm_crypt_request {
+ struct convert_context *ctx;
struct scatterlist sg_in;
struct scatterlist sg_out;
};
struct workqueue_struct *io_queue;
struct workqueue_struct *crypt_queue;
- wait_queue_head_t writeq;
/*
* crypto related data
ctx->idx_out = bio_out ? bio_out->bi_idx : 0;
ctx->sector = sector + cc->iv_offset;
init_completion(&ctx->restart);
- atomic_set(&ctx->pending, 1);
+}
+
+static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
+ struct ablkcipher_request *req)
+{
+ return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
+}
+
+static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
+ struct dm_crypt_request *dmreq)
+{
+ return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
}
static int crypt_convert_block(struct crypt_config *cc,
u8 *iv;
int r = 0;
- dmreq = (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
+ dmreq = dmreq_of_req(cc, req);
iv = (u8 *)ALIGN((unsigned long)(dmreq + 1),
crypto_ablkcipher_alignmask(cc->tfm) + 1);
+ dmreq->ctx = ctx;
sg_init_table(&dmreq->sg_in, 1);
sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
bv_in->bv_offset + ctx->offset_in);
cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
ablkcipher_request_set_tfm(cc->req, cc->tfm);
ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG |
- CRYPTO_TFM_REQ_MAY_SLEEP,
- kcryptd_async_done, ctx);
+ CRYPTO_TFM_REQ_MAY_SLEEP,
+ kcryptd_async_done,
+ dmreq_of_req(cc, cc->req));
}
/*
{
int r;
+ atomic_set(&ctx->pending, 1);
+
while(ctx->idx_in < ctx->bio_in->bi_vcnt &&
ctx->idx_out < ctx->bio_out->bi_vcnt) {
/*
* Generate a new unfragmented bio with the given size
* This should never violate the device limitations
- * May return a smaller bio when running out of pages
+ * May return a smaller bio when running out of pages, indicated by
+ * *out_of_pages set to 1.
*/
-static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
+static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size,
+ unsigned *out_of_pages)
{
struct crypt_config *cc = io->target->private;
struct bio *clone;
return NULL;
clone_init(io, clone);
+ *out_of_pages = 0;
for (i = 0; i < nr_iovecs; i++) {
page = mempool_alloc(cc->page_pool, gfp_mask);
- if (!page)
+ if (!page) {
+ *out_of_pages = 1;
break;
+ }
/*
* if additional pages cannot be allocated without waiting,
}
}
+static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti,
+ struct bio *bio, sector_t sector)
+{
+ struct crypt_config *cc = ti->private;
+ struct dm_crypt_io *io;
+
+ io = mempool_alloc(cc->io_pool, GFP_NOIO);
+ io->target = ti;
+ io->base_bio = bio;
+ io->sector = sector;
+ io->error = 0;
+ io->base_io = NULL;
+ atomic_set(&io->pending, 0);
+
+ return io;
+}
+
+static void crypt_inc_pending(struct dm_crypt_io *io)
+{
+ atomic_inc(&io->pending);
+}
+
/*
* One of the bios was finished. Check for completion of
* the whole request and correctly clean up the buffer.
+ * If base_io is set, wait for the last fragment to complete.
*/
static void crypt_dec_pending(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->target->private;
+ struct bio *base_bio = io->base_bio;
+ struct dm_crypt_io *base_io = io->base_io;
+ int error = io->error;
if (!atomic_dec_and_test(&io->pending))
return;
- bio_endio(io->base_bio, io->error);
mempool_free(io, cc->io_pool);
+
+ if (likely(!base_io))
+ bio_endio(base_bio, error);
+ else {
+ if (error && !base_io->error)
+ base_io->error = error;
+ crypt_dec_pending(base_io);
+ }
}
/*
struct bio *base_bio = io->base_bio;
struct bio *clone;
- atomic_inc(&io->pending);
+ crypt_inc_pending(io);
/*
* The block layer might modify the bvec array, so always
static void kcryptd_io_write(struct dm_crypt_io *io)
{
struct bio *clone = io->ctx.bio_out;
- struct crypt_config *cc = io->target->private;
-
generic_make_request(clone);
- wake_up(&cc->writeq);
}
static void kcryptd_io(struct work_struct *work)
crypt_free_buffer_pages(cc, clone);
bio_put(clone);
io->error = -EIO;
+ crypt_dec_pending(io);
return;
}
BUG_ON(io->ctx.idx_out < clone->bi_vcnt);
clone->bi_sector = cc->start + io->sector;
- io->sector += bio_sectors(clone);
if (async)
kcryptd_queue_io(io);
- else {
- atomic_inc(&io->pending);
+ else
generic_make_request(clone);
- }
}
-static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io)
+static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
{
struct crypt_config *cc = io->target->private;
struct bio *clone;
+ struct dm_crypt_io *new_io;
+ int crypt_finished;
+ unsigned out_of_pages = 0;
unsigned remaining = io->base_bio->bi_size;
+ sector_t sector = io->sector;
int r;
/*
+ * Prevent io from disappearing until this function completes.
+ */
+ crypt_inc_pending(io);
+ crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
+
+ /*
* The allocated buffers can be smaller than the whole bio,
* so repeat the whole process until all the data can be handled.
*/
while (remaining) {
- clone = crypt_alloc_buffer(io, remaining);
+ clone = crypt_alloc_buffer(io, remaining, &out_of_pages);
if (unlikely(!clone)) {
io->error = -ENOMEM;
- return;
+ break;
}
io->ctx.bio_out = clone;
io->ctx.idx_out = 0;
remaining -= clone->bi_size;
+ sector += bio_sectors(clone);
+ crypt_inc_pending(io);
r = crypt_convert(cc, &io->ctx);
+ crypt_finished = atomic_dec_and_test(&io->ctx.pending);
- if (atomic_dec_and_test(&io->ctx.pending)) {
- /* processed, no running async crypto */
+ /* Encryption was already finished, submit io now */
+ if (crypt_finished) {
kcryptd_crypt_write_io_submit(io, r, 0);
+
+ /*
+ * If there was an error, do not try next fragments.
+ * For async, error is processed in async handler.
+ */
if (unlikely(r < 0))
- return;
- } else
- atomic_inc(&io->pending);
-
- /* out of memory -> run queues */
- if (unlikely(remaining)) {
- /* wait for async crypto then reinitialize pending */
- wait_event(cc->writeq, !atomic_read(&io->ctx.pending));
- atomic_set(&io->ctx.pending, 1);
- congestion_wait(WRITE, HZ/100);
- }
- }
-}
+ break;
-static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
-{
- struct crypt_config *cc = io->target->private;
+ io->sector = sector;
+ }
- /*
- * Prevent io from disappearing until this function completes.
- */
- atomic_inc(&io->pending);
+ /*
+ * Out of memory -> run queues
+ * But don't wait if split was due to the io size restriction
+ */
+ if (unlikely(out_of_pages))
+ congestion_wait(BLK_RW_ASYNC, HZ/100);
- crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector);
- kcryptd_crypt_write_convert_loop(io);
+ /*
+ * With async crypto it is unsafe to share the crypto context
+ * between fragments, so switch to a new dm_crypt_io structure.
+ */
+ if (unlikely(!crypt_finished && remaining)) {
+ new_io = crypt_io_alloc(io->target, io->base_bio,
+ sector);
+ crypt_inc_pending(new_io);
+ crypt_convert_init(cc, &new_io->ctx, NULL,
+ io->base_bio, sector);
+ new_io->ctx.idx_in = io->ctx.idx_in;
+ new_io->ctx.offset_in = io->ctx.offset_in;
+
+ /*
+ * Fragments after the first use the base_io
+ * pending count.
+ */
+ if (!io->base_io)
+ new_io->base_io = io;
+ else {
+ new_io->base_io = io->base_io;
+ crypt_inc_pending(io->base_io);
+ crypt_dec_pending(io);
+ }
+
+ io = new_io;
+ }
+ }
crypt_dec_pending(io);
}
struct crypt_config *cc = io->target->private;
int r = 0;
- atomic_inc(&io->pending);
+ crypt_inc_pending(io);
crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
io->sector);
static void kcryptd_async_done(struct crypto_async_request *async_req,
int error)
{
- struct convert_context *ctx = async_req->data;
+ struct dm_crypt_request *dmreq = async_req->data;
+ struct convert_context *ctx = dmreq->ctx;
struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
struct crypt_config *cc = io->target->private;
return;
}
- mempool_free(ablkcipher_request_cast(async_req), cc->req_pool);
+ mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
if (!atomic_dec_and_test(&ctx->pending))
return;
goto bad_cipher;
}
- /* Compatiblity mode for old dm-crypt cipher strings */
+ /* Compatibility mode for old dm-crypt cipher strings */
if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) {
chainmode = "cbc";
ivmode = "plain";
goto bad_page_pool;
}
- cc->bs = bioset_create(MIN_IOS, MIN_IOS);
+ cc->bs = bioset_create(MIN_IOS, 0);
if (!cc->bs) {
ti->error = "Cannot allocate crypt bioset";
goto bad_bs;
goto bad_crypt_queue;
}
- init_waitqueue_head(&cc->writeq);
+ ti->num_flush_requests = 1;
ti->private = cc;
return 0;
crypto_free_ablkcipher(tfm);
bad_cipher:
/* Must zero key material before freeing */
- memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8));
- kfree(cc);
+ kzfree(cc);
return -EINVAL;
}
dm_put_device(ti, cc->dev);
/* Must zero key material before freeing */
- memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8));
- kfree(cc);
+ kzfree(cc);
}
static int crypt_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
- struct crypt_config *cc = ti->private;
struct dm_crypt_io *io;
+ struct crypt_config *cc;
- io = mempool_alloc(cc->io_pool, GFP_NOIO);
- io->target = ti;
- io->base_bio = bio;
- io->sector = bio->bi_sector - ti->begin;
- io->error = 0;
- atomic_set(&io->pending, 0);
+ if (unlikely(bio_empty_barrier(bio))) {
+ cc = ti->private;
+ bio->bi_bdev = cc->dev->bdev;
+ return DM_MAPIO_REMAPPED;
+ }
+
+ io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin);
if (bio_data_dir(io->base_bio) == READ)
kcryptd_queue_io(io);
return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
}
+static int crypt_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct crypt_config *cc = ti->private;
+
+ return fn(ti, cc->dev, cc->start, ti->len, data);
+}
+
static struct target_type crypt_target = {
.name = "crypt",
- .version= {1, 6, 0},
+ .version = {1, 7, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,
.resume = crypt_resume,
.message = crypt_message,
.merge = crypt_merge,
+ .iterate_devices = crypt_iterate_devices,
};
static int __init dm_crypt_init(void)
static void __exit dm_crypt_exit(void)
{
- int r = dm_unregister_target(&crypt_target);
-
- if (r < 0)
- DMERR("unregister failed %d", r);
-
+ dm_unregister_target(&crypt_target);
kmem_cache_destroy(_crypt_io_pool);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff