Merge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6

[linux-2.6-omap-h63xx.git] / drivers / md / dm-crypt.c

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 682ef9e6acd3344d5bf8a19f4550de90331f37d3..ce26c84af064339f196a0a2eb62b0c55866408b2 100644 (file)
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -23,7 +23,7 @@
 #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)
@@ -56,6 +56,7 @@ struct dm_crypt_io {
        atomic_t pending;
        int error;
        sector_t sector;
+       struct dm_crypt_io *base_io;
 };
 
 struct dm_crypt_request {
@@ -93,7 +94,6 @@ struct crypt_config {
 
        struct workqueue_struct *io_queue;
        struct workqueue_struct *crypt_queue;
-       wait_queue_head_t writeq;
 
        /*
         * crypto related data
@@ -534,6 +534,7 @@ static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti,
        io->base_bio = bio;
        io->sector = sector;
        io->error = 0;
+       io->base_io = NULL;
        atomic_set(&io->pending, 0);
 
        return io;
@@ -547,6 +548,7 @@ static void crypt_inc_pending(struct dm_crypt_io *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)
 {
@@ -555,7 +557,14 @@ 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);
 }
 
@@ -646,10 +655,7 @@ static void kcryptd_io_read(struct dm_crypt_io *io)
 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)
@@ -688,7 +694,6 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
        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);
@@ -700,16 +705,18 @@ 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, io->sector);
+       crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
 
        /*
         * The allocated buffers can be smaller than the whole bio,
@@ -726,6 +733,7 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
                io->ctx.idx_out = 0;
 
                remaining -= clone->bi_size;
+               sector += bio_sectors(clone);
 
                crypt_inc_pending(io);
                r = crypt_convert(cc, &io->ctx);
@@ -741,6 +749,8 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
                         */
                        if (unlikely(r < 0))
                                break;
+
+                       io->sector = sector;
                }
 
                /*
@@ -750,8 +760,33 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
                if (unlikely(out_of_pages))
                        congestion_wait(WRITE, HZ/100);
 
-               if (unlikely(remaining))
-                       wait_event(cc->writeq, !atomic_read(&io->ctx.pending));
+               /*
+                * 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);
@@ -1078,7 +1113,6 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                goto bad_crypt_queue;
        }
 
-       init_waitqueue_head(&cc->writeq);
        ti->private = cc;
        return 0;