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Merge branch 'linux-kernel-disk' into refs/top-bases/linux-zfs-branch

This commit is contained in:
Brian Behlendorf 2009-09-02 15:26:43 -07:00
parent c80d8efea2 c39498254d
commit 159833d991
1 changed files with 84 additions and 56 deletions
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140
module/zfs/vdev_disk.c
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@ -36,9 +36,8 @@
*/
typedef struct dio_request {
struct completion dr_comp; /* Completion for sync IO */
spinlock_t dr_lock; /* Completion lock */
atomic_t dr_ref; /* References */
zio_t *dr_zio; /* Parent ZIO */
int dr_ref; /* Outstanding bio count */
int dr_rw; /* Read/Write */
int dr_error; /* Bio error */
int dr_bio_count; /* Count of bio's */
@ -152,11 +151,72 @@ vdev_disk_close(vdev_t *v)
v->vdev_tsd = NULL;
}
BIO_END_IO_PROTO(vdev_disk_physio_completion, bio, size, rc)
static dio_request_t *
vdev_disk_dio_alloc(int bio_count)
{
dio_request_t *dr;
int i;
dr = kmem_zalloc(sizeof(dio_request_t) +
sizeof(struct bio *) * bio_count, KM_SLEEP);
if (dr) {
init_completion(&dr->dr_comp);
atomic_set(&dr->dr_ref, 0);
dr->dr_bio_count = bio_count;
dr->dr_error = 0;
for (i = 0; i < dr->dr_bio_count; i++)
dr->dr_bio[i] = NULL;
}
return dr;
}
static void
vdev_disk_dio_free(dio_request_t *dr)
{
int i;
for (i = 0; i < dr->dr_bio_count; i++)
if (dr->dr_bio[i])
bio_put(dr->dr_bio[i]);
kmem_free(dr, sizeof(dio_request_t) +
sizeof(struct bio *) * dr->dr_bio_count);
}
static void
vdev_disk_dio_get(dio_request_t *dr)
{
atomic_inc(&dr->dr_ref);
}
static int
vdev_disk_dio_put(dio_request_t *dr)
{
int rc = atomic_dec_return(&dr->dr_ref);
/* Free the dio_request when the last reference is dropped and
* ensure zio_interpret is called only once with the correct zio */
if (rc == 0) {
zio_t *zio = dr->dr_zio;
int error = dr->dr_error;
vdev_disk_dio_free(dr);
if (zio) {
zio->io_error = error;
zio_interrupt(zio);
}
}
return rc;
}
BIO_END_IO_PROTO(vdev_disk_physio_completion, bio, size, error)
{
dio_request_t *dr = bio->bi_private;
zio_t *zio;
int i, error;
int rc;
/* Fatal error but print some useful debugging before asserting */
if (dr == NULL) {
@ -174,43 +234,18 @@ BIO_END_IO_PROTO(vdev_disk_physio_completion, bio, size, rc)
return 1;
#endif /* HAVE_2ARGS_BIO_END_IO_T */
error = rc;
if (error == 0 && !test_bit(BIO_UPTODATE, &bio->bi_flags))
error = EIO;
spin_lock(&dr->dr_lock);
dr->dr_ref--;
if (dr->dr_error == 0)
dr->dr_error = error;
/*
* All bio's attached to this dio request have completed. This
* means it is safe to access the dio outside the spin lock, we
* are assured there will be no racing accesses.
*/
if (dr->dr_ref == 0) {
zio = dr->dr_zio;
spin_unlock(&dr->dr_lock);
/* Drop reference aquired by __vdev_disk_physio */
rc = vdev_disk_dio_put(dr);
/* Synchronous dio cleanup handled by waiter */
if (dr->dr_rw & (1 << DIO_RW_SYNCIO)) {
complete(&dr->dr_comp);
} else {
for (i = 0; i < dr->dr_bio_count; i++)
bio_put(dr->dr_bio[i]);
kmem_free(dr, sizeof(dio_request_t) +
sizeof(struct bio *) * dr->dr_bio_count);
}
if (zio) {
zio->io_error = dr->dr_error;
zio_interrupt(zio);
}
} else {
spin_unlock(&dr->dr_lock);
}
/* Wake up synchronous waiter this is the last outstanding bio */
if ((rc == 1) && (dr->dr_rw & (1 << DIO_RW_SYNCIO)))
complete(&dr->dr_comp);
BIO_END_IO_RETURN(0);
}
@ -277,7 +312,7 @@ __vdev_disk_physio(struct block_device *bdev, zio_t *zio, caddr_t kbuf_ptr,
dio_request_t *dr;
caddr_t bio_ptr;
uint64_t bio_offset;
int i, j, error = 0, bio_count, bio_size, dio_size;
int i, error = 0, bio_count, bio_size;
ASSERT3S(kbuf_offset % SECTOR_SIZE, ==, 0);
q = bdev_get_queue(bdev);
@ -285,18 +320,12 @@ __vdev_disk_physio(struct block_device *bdev, zio_t *zio, caddr_t kbuf_ptr,
return ENXIO;
bio_count = (kbuf_size / (q->max_hw_sectors << 9)) + 1;
dio_size = sizeof(dio_request_t) + sizeof(struct bio *) * bio_count;
dr = kmem_zalloc(dio_size, KM_SLEEP);
dr = vdev_disk_dio_alloc(bio_count);
if (dr == NULL)
return ENOMEM;
init_completion(&dr->dr_comp);
spin_lock_init(&dr->dr_lock);
dr->dr_ref = 0;
dr->dr_zio = zio;
dr->dr_rw = flags;
dr->dr_error = 0;
dr->dr_bio_count = bio_count;
#ifdef BIO_RW_FAILFAST
if (flags & (1 << BIO_RW_FAILFAST))
@ -317,47 +346,46 @@ __vdev_disk_physio(struct block_device *bdev, zio_t *zio, caddr_t kbuf_ptr,
dr->dr_bio[i] = bio_map(q, bio_ptr, bio_size, GFP_NOIO);
if (IS_ERR(dr->dr_bio[i])) {
for (j = 0; j < i; j++)
bio_put(dr->dr_bio[j]);
error = -PTR_ERR(dr->dr_bio[i]);
kmem_free(dr, dio_size);
vdev_disk_dio_free(dr);
return error;
}
/* Matching put called by vdev_disk_physio_completion */
vdev_disk_dio_get(dr);
dr->dr_bio[i]->bi_bdev = bdev;
dr->dr_bio[i]->bi_sector = bio_offset >> 9;
dr->dr_bio[i]->bi_end_io = vdev_disk_physio_completion;
dr->dr_bio[i]->bi_private = dr;
dr->dr_ref++;
bio_ptr += bio_size;
bio_offset += bio_size;
kbuf_size -= bio_size;
}
/* Extra reference to protect dio_request during submit_bio */
vdev_disk_dio_get(dr);
for (i = 0; i < dr->dr_bio_count; i++)
submit_bio(dr->dr_rw, dr->dr_bio[i]);
/*
* On synchronous blocking requests we wait for all bio the completion
* callbacks to run. We will be woken when the last callback runs
* for this dio. We are responsible for freeing the dio_request_t as
* well as the final reference on all attached bios. Currently, the
* for this dio. We are responsible for putting the last dio_request
* reference will in turn put back the last bio references. The
* only synchronous consumer is vdev_disk_read_rootlabel() all other
* IO originating from vdev_disk_io_start() is asynchronous.
*/
if (dr->dr_rw & (1 << DIO_RW_SYNCIO)) {
wait_for_completion(&dr->dr_comp);
ASSERT(dr->dr_ref == 0);
error = dr->dr_error;
for (i = 0; i < dr->dr_bio_count; i++)
bio_put(dr->dr_bio[i]);
kmem_free(dr, dio_size);
ASSERT3S(atomic_read(&dr->dr_ref), ==, 1);
}
(void)vdev_disk_dio_put(dr);
return error;
}