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authorIngo Molnar <mingo@elte.hu>2008-10-12 14:35:23 +0400
committerIngo Molnar <mingo@elte.hu>2008-10-12 14:37:32 +0400
commit365d46dc9be9b3c833990a06f3994b1987eda578 (patch)
tree9397d1304144a288411f2118707f44ff5e862fa6 /drivers/md/dm-crypt.c
parent5dc64a3442b98eaa0e3730c35fcf00cf962a93e7 (diff)
parentfd048088306656824958e7783ffcee27e241b361 (diff)
downloadlinux-365d46dc9be9b3c833990a06f3994b1987eda578.tar.xz
Merge branch 'linus' into x86/xen
Conflicts: arch/x86/kernel/cpu/common.c arch/x86/kernel/process_64.c arch/x86/xen/enlighten.c
Diffstat (limited to 'drivers/md/dm-crypt.c')
-rw-r--r--drivers/md/dm-crypt.c109
1 files changed, 66 insertions, 43 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 13956437bc81..682ef9e6acd3 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -333,7 +333,6 @@ static void crypt_convert_init(struct crypt_config *cc,
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,
@@ -408,6 +407,8 @@ static int crypt_convert(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) {
@@ -456,9 +457,11 @@ static void dm_crypt_bio_destructor(struct bio *bio)
/*
* 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;
@@ -472,11 +475,14 @@ static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
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,
@@ -517,6 +523,27 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
}
}
+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;
+ 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.
@@ -591,7 +618,7 @@ static void kcryptd_io_read(struct dm_crypt_io *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
@@ -653,6 +680,7 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
crypt_free_buffer_pages(cc, clone);
bio_put(clone);
io->error = -EIO;
+ crypt_dec_pending(io);
return;
}
@@ -664,28 +692,34 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
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;
+ int crypt_finished;
+ unsigned out_of_pages = 0;
unsigned remaining = io->base_bio->bi_size;
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);
+
+ /*
* 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;
@@ -693,37 +727,32 @@ static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io)
remaining -= clone->bi_size;
+ 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 (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);
+ /*
+ * If there was an error, do not try next fragments.
+ * For async, error is processed in async handler.
+ */
+ if (unlikely(r < 0))
+ break;
}
- }
-}
-static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
-{
- struct crypt_config *cc = io->target->private;
-
- /*
- * 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(WRITE, HZ/100);
- crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector);
- kcryptd_crypt_write_convert_loop(io);
+ if (unlikely(remaining))
+ wait_event(cc->writeq, !atomic_read(&io->ctx.pending));
+ }
crypt_dec_pending(io);
}
@@ -741,7 +770,7 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *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);
@@ -1108,15 +1137,9 @@ static void crypt_dtr(struct dm_target *ti)
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;
- 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);
+ io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin);
if (bio_data_dir(io->base_bio) == READ)
kcryptd_queue_io(io);