#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 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 int crypt_convert_block(struct crypt_config *cc,
{
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,
io->base_bio = bio;
io->sector = sector;
io->error = 0;
+ io->base_io = NULL;
atomic_set(&io->pending, 0);
return io;
/*
* 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)
{
if (!atomic_dec_and_test(&io->pending))
return;
- bio_endio(io->base_bio, io->error);
+ if (likely(!io->base_io))
+ bio_endio(io->base_bio, io->error);
+ else {
+ if (io->error && !io->base_io->error)
+ io->base_io->error = io->error;
+ crypt_dec_pending(io->base_io);
+ }
+
mempool_free(io, cc->io_pool);
}
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)
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);
{
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, io->sector);
+ 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;
break;
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 */
- crypt_inc_pending(io);
+ /* 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))
break;
- } else
- crypt_inc_pending(io);
-
- /* 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);
+
+ io->sector = sector;
+ }
+
+ /*
+ * 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(WRITE, HZ/100);
+
+ /*
+ * 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;
}
}
goto bad_crypt_queue;
}
- init_waitqueue_head(&cc->writeq);
ti->private = cc;
return 0;
projects / linux-2.6-omap-h63xx.git / blobdiff