dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock
[pandora-kernel.git] / drivers / md / dm-io.c
index ad2eba4..b8ed01b 100644 (file)
@@ -10,6 +10,7 @@
 #include <linux/device-mapper.h>
 
 #include <linux/bio.h>
+#include <linux/completion.h>
 #include <linux/mempool.h>
 #include <linux/module.h>
 #include <linux/sched.h>
@@ -34,7 +35,7 @@ struct dm_io_client {
 struct io {
        unsigned long error_bits;
        atomic_t count;
-       struct task_struct *sleeper;
+       struct completion *wait;
        struct dm_io_client *client;
        io_notify_fn callback;
        void *context;
@@ -122,8 +123,8 @@ static void dec_count(struct io *io, unsigned int region, int error)
                        invalidate_kernel_vmap_range(io->vma_invalidate_address,
                                                     io->vma_invalidate_size);
 
-               if (io->sleeper)
-                       wake_up_process(io->sleeper);
+               if (io->wait)
+                       complete(io->wait);
 
                else {
                        unsigned long r = io->error_bits;
@@ -296,6 +297,18 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
        unsigned offset;
        unsigned num_bvecs;
        sector_t remaining = where->count;
+       struct request_queue *q = bdev_get_queue(where->bdev);
+       sector_t discard_sectors;
+       unsigned int uninitialized_var(special_cmd_max_sectors);
+
+       /* Reject unsupported discard requests */
+       if (rw & REQ_DISCARD) {
+               special_cmd_max_sectors = q->limits.max_discard_sectors;
+               if (special_cmd_max_sectors == 0) {
+                       dec_count(io, region, -EOPNOTSUPP);
+                       return;
+               }
+       }
 
        /*
         * where->count may be zero if rw holds a flush and we need to
@@ -305,9 +318,12 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
                /*
                 * Allocate a suitably sized-bio.
                 */
-               num_bvecs = dm_sector_div_up(remaining,
-                                            (PAGE_SIZE >> SECTOR_SHIFT));
-               num_bvecs = min_t(int, bio_get_nr_vecs(where->bdev), num_bvecs);
+               if (rw & REQ_DISCARD)
+                       num_bvecs = 1;
+               else
+                       num_bvecs = min_t(int, bio_get_nr_vecs(where->bdev),
+                                         dm_sector_div_up(remaining, (PAGE_SIZE >> SECTOR_SHIFT)));
+
                bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, io->client->bios);
                bio->bi_sector = where->sector + (where->count - remaining);
                bio->bi_bdev = where->bdev;
@@ -315,10 +331,14 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
                bio->bi_destructor = dm_bio_destructor;
                store_io_and_region_in_bio(bio, io, region);
 
-               /*
-                * Try and add as many pages as possible.
-                */
-               while (remaining) {
+               if (rw & REQ_DISCARD) {
+                       discard_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
+                       bio->bi_size = discard_sectors << SECTOR_SHIFT;
+                       remaining -= discard_sectors;
+               } else while (remaining) {
+                       /*
+                        * Try and add as many pages as possible.
+                        */
                        dp->get_page(dp, &page, &len, &offset);
                        len = min(len, to_bytes(remaining));
                        if (!bio_add_page(bio, page, len, offset))
@@ -375,6 +395,7 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
         */
        volatile char io_[sizeof(struct io) + __alignof__(struct io) - 1];
        struct io *io = (struct io *)PTR_ALIGN(&io_, __alignof__(struct io));
+       DECLARE_COMPLETION_ONSTACK(wait);
 
        if (num_regions > 1 && (rw & RW_MASK) != WRITE) {
                WARN_ON(1);
@@ -383,7 +404,7 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
 
        io->error_bits = 0;
        atomic_set(&io->count, 1); /* see dispatch_io() */
-       io->sleeper = current;
+       io->wait = &wait;
        io->client = client;
 
        io->vma_invalidate_address = dp->vma_invalidate_address;
@@ -391,15 +412,7 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
 
        dispatch_io(rw, num_regions, where, dp, io, 1);
 
-       while (1) {
-               set_current_state(TASK_UNINTERRUPTIBLE);
-
-               if (!atomic_read(&io->count))
-                       break;
-
-               io_schedule();
-       }
-       set_current_state(TASK_RUNNING);
+       wait_for_completion(&wait);
 
        if (error_bits)
                *error_bits = io->error_bits;
@@ -422,7 +435,7 @@ static int async_io(struct dm_io_client *client, unsigned int num_regions,
        io = mempool_alloc(client->pool, GFP_NOIO);
        io->error_bits = 0;
        atomic_set(&io->count, 1); /* see dispatch_io() */
-       io->sleeper = NULL;
+       io->wait = NULL;
        io->client = client;
        io->callback = fn;
        io->context = context;