#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/writeback.h>
+#include <linux/task_io_accounting_ops.h>
#include <linux/interrupt.h>
#include <linux/cpu.h>
#include <linux/blktrace_api.h>
+#include <linux/fault-inject.h>
/*
* for max sense size
*/
#include <scsi/scsi_cmnd.h>
-static void blk_unplug_work(void *data);
+static void blk_unplug_work(struct work_struct *work);
static void blk_unplug_timeout(unsigned long data);
static void drive_stat_acct(struct request *rq, int nr_sectors, int new_io);
static void init_request_from_bio(struct request *req, struct bio *bio);
/*
* For the allocated request tables
*/
-static kmem_cache_t *request_cachep;
+static struct kmem_cache *request_cachep;
/*
* For queue allocation
*/
-static kmem_cache_t *requestq_cachep;
+static struct kmem_cache *requestq_cachep;
/*
* For io context allocations
*/
-static kmem_cache_t *iocontext_cachep;
+static struct kmem_cache *iocontext_cachep;
/*
* Controlling structure to kblockd
}
EXPORT_SYMBOL(blk_get_backing_dev_info);
-void blk_queue_activity_fn(request_queue_t *q, activity_fn *fn, void *data)
-{
- q->activity_fn = fn;
- q->activity_data = data;
-}
-EXPORT_SYMBOL(blk_queue_activity_fn);
-
/**
* blk_queue_prep_rq - set a prepare_request function for queue
* @q: queue
if (q->unplug_delay == 0)
q->unplug_delay = 1;
- INIT_WORK(&q->unplug_work, blk_unplug_work, q);
+ INIT_WORK(&q->unplug_work, blk_unplug_work);
q->unplug_timer.function = blk_unplug_timeout;
q->unplug_timer.data = (unsigned long)q;
* by default assume old behaviour and bounce for any highmem page
*/
blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
-
- blk_queue_activity_fn(q, NULL, NULL);
}
EXPORT_SYMBOL(blk_queue_make_request);
return 1;
}
-static int ll_back_merge_fn(request_queue_t *q, struct request *req,
- struct bio *bio)
+int ll_back_merge_fn(request_queue_t *q, struct request *req, struct bio *bio)
{
unsigned short max_sectors;
int len;
return ll_new_hw_segment(q, req, bio);
}
+EXPORT_SYMBOL(ll_back_merge_fn);
static int ll_front_merge_fn(request_queue_t *q, struct request *req,
struct bio *bio)
}
}
-static void blk_unplug_work(void *data)
+static void blk_unplug_work(struct work_struct *work)
{
- request_queue_t *q = data;
+ request_queue_t *q = container_of(work, request_queue_t, unplug_work);
blk_add_trace_pdu_int(q, BLK_TA_UNPLUG_IO, NULL,
q->rq.count[READ] + q->rq.count[WRITE]);
}
q->request_fn = rfn;
- q->back_merge_fn = ll_back_merge_fn;
- q->front_merge_fn = ll_front_merge_fn;
- q->merge_requests_fn = ll_merge_requests_fn;
q->prep_rq_fn = NULL;
q->unplug_fn = generic_unplug_device;
q->queue_flags = (1 << QUEUE_FLAG_CLUSTER);
* Returns NULL on failure, with queue_lock held.
* Returns !NULL on success, with queue_lock *not held*.
*/
-static struct request *get_request(request_queue_t *q, int rw, struct bio *bio,
- gfp_t gfp_mask)
+static struct request *get_request(request_queue_t *q, int rw_flags,
+ struct bio *bio, gfp_t gfp_mask)
{
struct request *rq = NULL;
struct request_list *rl = &q->rq;
struct io_context *ioc = NULL;
+ const int rw = rw_flags & 0x01;
int may_queue, priv;
- may_queue = elv_may_queue(q, rw);
+ may_queue = elv_may_queue(q, rw_flags);
if (may_queue == ELV_MQUEUE_NO)
goto rq_starved;
spin_unlock_irq(q->queue_lock);
- rq = blk_alloc_request(q, rw, priv, gfp_mask);
+ rq = blk_alloc_request(q, rw_flags, priv, gfp_mask);
if (unlikely(!rq)) {
/*
* Allocation failed presumably due to memory. Undo anything
*
* Called with q->queue_lock held, and returns with it unlocked.
*/
-static struct request *get_request_wait(request_queue_t *q, int rw,
+static struct request *get_request_wait(request_queue_t *q, int rw_flags,
struct bio *bio)
{
+ const int rw = rw_flags & 0x01;
struct request *rq;
- rq = get_request(q, rw, bio, GFP_NOIO);
+ rq = get_request(q, rw_flags, bio, GFP_NOIO);
while (!rq) {
DEFINE_WAIT(wait);
struct request_list *rl = &q->rq;
prepare_to_wait_exclusive(&rl->wait[rw], &wait,
TASK_UNINTERRUPTIBLE);
- rq = get_request(q, rw, bio, GFP_NOIO);
+ rq = get_request(q, rw_flags, bio, GFP_NOIO);
if (!rq) {
struct io_context *ioc;
EXPORT_SYMBOL(blk_insert_request);
+static int __blk_rq_unmap_user(struct bio *bio)
+{
+ int ret = 0;
+
+ if (bio) {
+ if (bio_flagged(bio, BIO_USER_MAPPED))
+ bio_unmap_user(bio);
+ else
+ ret = bio_uncopy_user(bio);
+ }
+
+ return ret;
+}
+
+static int __blk_rq_map_user(request_queue_t *q, struct request *rq,
+ void __user *ubuf, unsigned int len)
+{
+ unsigned long uaddr;
+ struct bio *bio, *orig_bio;
+ int reading, ret;
+
+ reading = rq_data_dir(rq) == READ;
+
+ /*
+ * if alignment requirement is satisfied, map in user pages for
+ * direct dma. else, set up kernel bounce buffers
+ */
+ uaddr = (unsigned long) ubuf;
+ if (!(uaddr & queue_dma_alignment(q)) && !(len & queue_dma_alignment(q)))
+ bio = bio_map_user(q, NULL, uaddr, len, reading);
+ else
+ bio = bio_copy_user(q, uaddr, len, reading);
+
+ if (IS_ERR(bio))
+ return PTR_ERR(bio);
+
+ orig_bio = bio;
+ blk_queue_bounce(q, &bio);
+
+ /*
+ * We link the bounce buffer in and could have to traverse it
+ * later so we have to get a ref to prevent it from being freed
+ */
+ bio_get(bio);
+
+ if (!rq->bio)
+ blk_rq_bio_prep(q, rq, bio);
+ else if (!ll_back_merge_fn(q, rq, bio)) {
+ ret = -EINVAL;
+ goto unmap_bio;
+ } else {
+ rq->biotail->bi_next = bio;
+ rq->biotail = bio;
+
+ rq->data_len += bio->bi_size;
+ }
+
+ return bio->bi_size;
+
+unmap_bio:
+ /* if it was boucned we must call the end io function */
+ bio_endio(bio, bio->bi_size, 0);
+ __blk_rq_unmap_user(orig_bio);
+ bio_put(bio);
+ return ret;
+}
+
/**
* blk_rq_map_user - map user data to a request, for REQ_BLOCK_PC usage
* @q: request queue where request should be inserted
* unmapping.
*/
int blk_rq_map_user(request_queue_t *q, struct request *rq, void __user *ubuf,
- unsigned int len)
+ unsigned long len)
{
- unsigned long uaddr;
- struct bio *bio;
- int reading;
+ unsigned long bytes_read = 0;
+ struct bio *bio = NULL;
+ int ret;
if (len > (q->max_hw_sectors << 9))
return -EINVAL;
if (!len || !ubuf)
return -EINVAL;
- reading = rq_data_dir(rq) == READ;
+ while (bytes_read != len) {
+ unsigned long map_len, end, start;
- /*
- * if alignment requirement is satisfied, map in user pages for
- * direct dma. else, set up kernel bounce buffers
- */
- uaddr = (unsigned long) ubuf;
- if (!(uaddr & queue_dma_alignment(q)) && !(len & queue_dma_alignment(q)))
- bio = bio_map_user(q, NULL, uaddr, len, reading);
- else
- bio = bio_copy_user(q, uaddr, len, reading);
+ map_len = min_t(unsigned long, len - bytes_read, BIO_MAX_SIZE);
+ end = ((unsigned long)ubuf + map_len + PAGE_SIZE - 1)
+ >> PAGE_SHIFT;
+ start = (unsigned long)ubuf >> PAGE_SHIFT;
- if (!IS_ERR(bio)) {
- rq->bio = rq->biotail = bio;
- blk_rq_bio_prep(q, rq, bio);
+ /*
+ * A bad offset could cause us to require BIO_MAX_PAGES + 1
+ * pages. If this happens we just lower the requested
+ * mapping len by a page so that we can fit
+ */
+ if (end - start > BIO_MAX_PAGES)
+ map_len -= PAGE_SIZE;
- rq->buffer = rq->data = NULL;
- rq->data_len = len;
- return 0;
+ ret = __blk_rq_map_user(q, rq, ubuf, map_len);
+ if (ret < 0)
+ goto unmap_rq;
+ if (!bio)
+ bio = rq->bio;
+ bytes_read += ret;
+ ubuf += ret;
}
- /*
- * bio is the err-ptr
- */
- return PTR_ERR(bio);
+ rq->buffer = rq->data = NULL;
+ return 0;
+unmap_rq:
+ blk_rq_unmap_user(bio);
+ return ret;
}
EXPORT_SYMBOL(blk_rq_map_user);
* @rq: request to map data to
* @iov: pointer to the iovec
* @iov_count: number of elements in the iovec
+ * @len: I/O byte count
*
* Description:
* Data will be mapped directly for zero copy io, if possible. Otherwise
* unmapping.
*/
int blk_rq_map_user_iov(request_queue_t *q, struct request *rq,
- struct sg_iovec *iov, int iov_count)
+ struct sg_iovec *iov, int iov_count, unsigned int len)
{
struct bio *bio;
if (IS_ERR(bio))
return PTR_ERR(bio);
- rq->bio = rq->biotail = bio;
+ if (bio->bi_size != len) {
+ bio_endio(bio, bio->bi_size, 0);
+ bio_unmap_user(bio);
+ return -EINVAL;
+ }
+
+ bio_get(bio);
blk_rq_bio_prep(q, rq, bio);
rq->buffer = rq->data = NULL;
- rq->data_len = bio->bi_size;
return 0;
}
/**
* blk_rq_unmap_user - unmap a request with user data
- * @bio: bio to be unmapped
- * @ulen: length of user buffer
+ * @bio: start of bio list
*
* Description:
- * Unmap a bio previously mapped by blk_rq_map_user().
+ * Unmap a rq previously mapped by blk_rq_map_user(). The caller must
+ * supply the original rq->bio from the blk_rq_map_user() return, since
+ * the io completion may have changed rq->bio.
*/
-int blk_rq_unmap_user(struct bio *bio, unsigned int ulen)
+int blk_rq_unmap_user(struct bio *bio)
{
- int ret = 0;
+ struct bio *mapped_bio;
+ int ret = 0, ret2;
- if (bio) {
- if (bio_flagged(bio, BIO_USER_MAPPED))
- bio_unmap_user(bio);
- else
- ret = bio_uncopy_user(bio);
+ while (bio) {
+ mapped_bio = bio;
+ if (unlikely(bio_flagged(bio, BIO_BOUNCED)))
+ mapped_bio = bio->bi_private;
+
+ ret2 = __blk_rq_unmap_user(mapped_bio);
+ if (ret2 && !ret)
+ ret = ret2;
+
+ mapped_bio = bio;
+ bio = bio->bi_next;
+ bio_put(mapped_bio);
}
- return 0;
+ return ret;
}
EXPORT_SYMBOL(blk_rq_unmap_user);
if (rq_data_dir(rq) == WRITE)
bio->bi_rw |= (1 << BIO_RW);
- rq->bio = rq->biotail = bio;
blk_rq_bio_prep(q, rq, bio);
-
rq->buffer = rq->data = NULL;
- rq->data_len = len;
return 0;
}
{
drive_stat_acct(req, req->nr_sectors, 1);
- if (q->activity_fn)
- q->activity_fn(q->activity_data, rq_data_dir(req));
-
/*
* elevator indicated where it wants this request to be
* inserted at elevator_merge time
* will have updated segment counts, update sector
* counts here.
*/
- if (!q->merge_requests_fn(q, req, next))
+ if (!ll_merge_requests_fn(q, req, next))
return 0;
/*
int el_ret, nr_sectors, barrier, err;
const unsigned short prio = bio_prio(bio);
const int sync = bio_sync(bio);
+ int rw_flags;
nr_sectors = bio_sectors(bio);
case ELEVATOR_BACK_MERGE:
BUG_ON(!rq_mergeable(req));
- if (!q->back_merge_fn(q, req, bio))
+ if (!ll_back_merge_fn(q, req, bio))
break;
blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
case ELEVATOR_FRONT_MERGE:
BUG_ON(!rq_mergeable(req));
- if (!q->front_merge_fn(q, req, bio))
+ if (!ll_front_merge_fn(q, req, bio))
break;
blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);
}
get_rq:
+ /*
+ * This sync check and mask will be re-done in init_request_from_bio(),
+ * but we need to set it earlier to expose the sync flag to the
+ * rq allocator and io schedulers.
+ */
+ rw_flags = bio_data_dir(bio);
+ if (sync)
+ rw_flags |= REQ_RW_SYNC;
+
/*
* Grab a free request. This is might sleep but can not fail.
* Returns with the queue unlocked.
*/
- req = get_request_wait(q, bio_data_dir(bio), bio);
+ req = get_request_wait(q, rw_flags, bio);
/*
* After dropping the lock and possibly sleeping here, our request
set_bit(BIO_EOF, &bio->bi_flags);
}
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+
+static DECLARE_FAULT_ATTR(fail_make_request);
+
+static int __init setup_fail_make_request(char *str)
+{
+ return setup_fault_attr(&fail_make_request, str);
+}
+__setup("fail_make_request=", setup_fail_make_request);
+
+static int should_fail_request(struct bio *bio)
+{
+ if ((bio->bi_bdev->bd_disk->flags & GENHD_FL_FAIL) ||
+ (bio->bi_bdev->bd_part && bio->bi_bdev->bd_part->make_it_fail))
+ return should_fail(&fail_make_request, bio->bi_size);
+
+ return 0;
+}
+
+static int __init fail_make_request_debugfs(void)
+{
+ return init_fault_attr_dentries(&fail_make_request,
+ "fail_make_request");
+}
+
+late_initcall(fail_make_request_debugfs);
+
+#else /* CONFIG_FAIL_MAKE_REQUEST */
+
+static inline int should_fail_request(struct bio *bio)
+{
+ return 0;
+}
+
+#endif /* CONFIG_FAIL_MAKE_REQUEST */
+
/**
* generic_make_request: hand a buffer to its device driver for I/O
* @bio: The bio describing the location in memory and on the device.
if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
goto end_io;
+ if (should_fail_request(bio))
+ goto end_io;
+
/*
* If this device has partitions, remap block n
* of partition p to block n+start(p) of the disk.
BIO_BUG_ON(!bio->bi_size);
BIO_BUG_ON(!bio->bi_io_vec);
bio->bi_rw |= rw;
- if (rw & WRITE)
+ if (rw & WRITE) {
count_vm_events(PGPGOUT, count);
- else
+ } else {
+ task_io_account_read(bio->bi_size);
count_vm_events(PGPGIN, count);
+ }
if (unlikely(block_dump)) {
char b[BDEVNAME_SIZE];
}
}
-#ifdef CONFIG_HOTPLUG_CPU
-
static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
void *hcpu)
{
.notifier_call = blk_cpu_notify,
};
-#endif /* CONFIG_HOTPLUG_CPU */
-
/**
* blk_complete_request - end I/O on a request
* @req: the request being processed
rq->hard_cur_sectors = rq->current_nr_sectors;
rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio);
rq->buffer = bio_data(bio);
+ rq->data_len = bio->bi_size;
rq->bio = rq->biotail = bio;
}
git.openpandora.org / pandora-kernel.git / blobdiff