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-rw-r--r--block/Makefile3
-rw-r--r--block/bfq-cgroup.c87
-rw-r--r--block/bfq-iosched.c18
-rw-r--r--block/bfq-iosched.h1
-rw-r--r--block/bio.c580
-rw-r--r--block/blk-cgroup.c2
-rw-r--r--block/blk-core.c82
-rw-r--r--block/blk-flush.c16
-rw-r--r--block/blk-ioc.c7
-rw-r--r--block/blk-iocost.c5
-rw-r--r--block/blk-map.c508
-rw-r--r--block/blk-mq-sched.c22
-rw-r--r--block/blk-mq.c50
-rw-r--r--block/blk-settings.c36
-rw-r--r--block/blk-zoned.c2
-rw-r--r--block/blk.h138
-rw-r--r--block/genhd.c255
-rw-r--r--block/ioctl.c1
-rw-r--r--block/opal_proto.h1
-rw-r--r--block/partitions/Makefile3
-rw-r--r--block/partitions/acorn.c1
-rw-r--r--block/partitions/acorn.h15
-rw-r--r--block/partitions/aix.c1
-rw-r--r--block/partitions/aix.h2
-rw-r--r--block/partitions/amiga.c11
-rw-r--r--block/partitions/amiga.h7
-rw-r--r--block/partitions/atari.h1
-rw-r--r--block/partitions/check.c198
-rw-r--r--block/partitions/check.h41
-rw-r--r--block/partitions/cmdline.c1
-rw-r--r--block/partitions/cmdline.h3
-rw-r--r--block/partitions/core.c (renamed from block/partition-generic.c)319
-rw-r--r--block/partitions/efi.h3
-rw-r--r--block/partitions/ibm.c1
-rw-r--r--block/partitions/ibm.h2
-rw-r--r--block/partitions/karma.c3
-rw-r--r--block/partitions/karma.h9
-rw-r--r--block/partitions/ldm.c6
-rw-r--r--block/partitions/ldm.h2
-rw-r--r--block/partitions/mac.h1
-rw-r--r--block/partitions/msdos.c172
-rw-r--r--block/partitions/msdos.h9
-rw-r--r--block/partitions/osf.c2
-rw-r--r--block/partitions/osf.h8
-rw-r--r--block/partitions/sgi.c7
-rw-r--r--block/partitions/sgi.h9
-rw-r--r--block/partitions/sun.c9
-rw-r--r--block/partitions/sun.h9
-rw-r--r--block/partitions/sysv68.c1
-rw-r--r--block/partitions/sysv68.h2
-rw-r--r--block/partitions/ultrix.c1
-rw-r--r--block/partitions/ultrix.h6
-rw-r--r--block/sed-opal.c2
53 files changed, 1489 insertions, 1192 deletions
diff --git a/block/Makefile b/block/Makefile
index 1a43750f4b01..206b96e9387f 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -8,8 +8,7 @@ obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-sysfs.o \
blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \
blk-mq-sysfs.o blk-mq-cpumap.o blk-mq-sched.o ioctl.o \
- genhd.o partition-generic.o ioprio.o \
- badblocks.o partitions/ blk-rq-qos.o
+ genhd.o ioprio.o badblocks.o partitions/ blk-rq-qos.o
obj-$(CONFIG_BOUNCE) += bounce.o
obj-$(CONFIG_BLK_SCSI_REQUEST) += scsi_ioctl.o
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index f0ff6654af28..68882b9b8f11 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -642,6 +642,12 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
{
struct bfq_entity *entity = &bfqq->entity;
+ /*
+ * Get extra reference to prevent bfqq from being freed in
+ * next possible expire or deactivate.
+ */
+ bfqq->ref++;
+
/* If bfqq is empty, then bfq_bfqq_expire also invokes
* bfq_del_bfqq_busy, thereby removing bfqq and its entity
* from data structures related to current group. Otherwise we
@@ -652,12 +658,6 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
bfq_bfqq_expire(bfqd, bfqd->in_service_queue,
false, BFQQE_PREEMPTED);
- /*
- * get extra reference to prevent bfqq from being freed in
- * next possible deactivate
- */
- bfqq->ref++;
-
if (bfq_bfqq_busy(bfqq))
bfq_deactivate_bfqq(bfqd, bfqq, false, false);
else if (entity->on_st_or_in_serv)
@@ -677,7 +677,7 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
if (!bfqd->in_service_queue && !bfqd->rq_in_driver)
bfq_schedule_dispatch(bfqd);
- /* release extra ref taken above */
+ /* release extra ref taken above, bfqq may happen to be freed now */
bfq_put_queue(bfqq);
}
@@ -714,10 +714,7 @@ static struct bfq_group *__bfq_bic_change_cgroup(struct bfq_data *bfqd,
if (entity->sched_data != &bfqg->sched_data) {
bic_set_bfqq(bic, NULL, 0);
- bfq_log_bfqq(bfqd, async_bfqq,
- "bic_change_group: %p %d",
- async_bfqq, async_bfqq->ref);
- bfq_put_queue(async_bfqq);
+ bfq_release_process_ref(bfqd, async_bfqq);
}
}
@@ -818,39 +815,53 @@ static void bfq_flush_idle_tree(struct bfq_service_tree *st)
/**
* bfq_reparent_leaf_entity - move leaf entity to the root_group.
* @bfqd: the device data structure with the root group.
- * @entity: the entity to move.
+ * @entity: the entity to move, if entity is a leaf; or the parent entity
+ * of an active leaf entity to move, if entity is not a leaf.
*/
static void bfq_reparent_leaf_entity(struct bfq_data *bfqd,
- struct bfq_entity *entity)
+ struct bfq_entity *entity,
+ int ioprio_class)
{
- struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity);
+ struct bfq_queue *bfqq;
+ struct bfq_entity *child_entity = entity;
+ while (child_entity->my_sched_data) { /* leaf not reached yet */
+ struct bfq_sched_data *child_sd = child_entity->my_sched_data;
+ struct bfq_service_tree *child_st = child_sd->service_tree +
+ ioprio_class;
+ struct rb_root *child_active = &child_st->active;
+
+ child_entity = bfq_entity_of(rb_first(child_active));
+
+ if (!child_entity)
+ child_entity = child_sd->in_service_entity;
+ }
+
+ bfqq = bfq_entity_to_bfqq(child_entity);
bfq_bfqq_move(bfqd, bfqq, bfqd->root_group);
}
/**
- * bfq_reparent_active_entities - move to the root group all active
- * entities.
+ * bfq_reparent_active_queues - move to the root group all active queues.
* @bfqd: the device data structure with the root group.
* @bfqg: the group to move from.
- * @st: the service tree with the entities.
+ * @st: the service tree to start the search from.
*/
-static void bfq_reparent_active_entities(struct bfq_data *bfqd,
- struct bfq_group *bfqg,
- struct bfq_service_tree *st)
+static void bfq_reparent_active_queues(struct bfq_data *bfqd,
+ struct bfq_group *bfqg,
+ struct bfq_service_tree *st,
+ int ioprio_class)
{
struct rb_root *active = &st->active;
- struct bfq_entity *entity = NULL;
-
- if (!RB_EMPTY_ROOT(&st->active))
- entity = bfq_entity_of(rb_first(active));
+ struct bfq_entity *entity;
- for (; entity ; entity = bfq_entity_of(rb_first(active)))
- bfq_reparent_leaf_entity(bfqd, entity);
+ while ((entity = bfq_entity_of(rb_first(active))))
+ bfq_reparent_leaf_entity(bfqd, entity, ioprio_class);
if (bfqg->sched_data.in_service_entity)
bfq_reparent_leaf_entity(bfqd,
- bfqg->sched_data.in_service_entity);
+ bfqg->sched_data.in_service_entity,
+ ioprio_class);
}
/**
@@ -883,13 +894,6 @@ static void bfq_pd_offline(struct blkg_policy_data *pd)
st = bfqg->sched_data.service_tree + i;
/*
- * The idle tree may still contain bfq_queues belonging
- * to exited task because they never migrated to a different
- * cgroup from the one being destroyed now.
- */
- bfq_flush_idle_tree(st);
-
- /*
* It may happen that some queues are still active
* (busy) upon group destruction (if the corresponding
* processes have been forced to terminate). We move
@@ -901,7 +905,20 @@ static void bfq_pd_offline(struct blkg_policy_data *pd)
* There is no need to put the sync queues, as the
* scheduler has taken no reference.
*/
- bfq_reparent_active_entities(bfqd, bfqg, st);
+ bfq_reparent_active_queues(bfqd, bfqg, st, i);
+
+ /*
+ * The idle tree may still contain bfq_queues
+ * belonging to exited task because they never
+ * migrated to a different cgroup from the one being
+ * destroyed now. In addition, even
+ * bfq_reparent_active_queues() may happen to add some
+ * entities to the idle tree. It happens if, in some
+ * of the calls to bfq_bfqq_move() performed by
+ * bfq_reparent_active_queues(), the queue to move is
+ * empty and gets expired.
+ */
+ bfq_flush_idle_tree(st);
}
__bfq_deactivate_entity(entity, false);
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 8c436abfaf14..78ba57efd16b 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -2716,8 +2716,6 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
}
}
-
-static
void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq)
{
/*
@@ -6215,20 +6213,28 @@ static struct bfq_queue *bfq_init_rq(struct request *rq)
return bfqq;
}
-static void bfq_idle_slice_timer_body(struct bfq_queue *bfqq)
+static void
+bfq_idle_slice_timer_body(struct bfq_data *bfqd, struct bfq_queue *bfqq)
{
- struct bfq_data *bfqd = bfqq->bfqd;
enum bfqq_expiration reason;
unsigned long flags;
spin_lock_irqsave(&bfqd->lock, flags);
- bfq_clear_bfqq_wait_request(bfqq);
+ /*
+ * Considering that bfqq may be in race, we should firstly check
+ * whether bfqq is in service before doing something on it. If
+ * the bfqq in race is not in service, it has already been expired
+ * through __bfq_bfqq_expire func and its wait_request flags has
+ * been cleared in __bfq_bfqd_reset_in_service func.
+ */
if (bfqq != bfqd->in_service_queue) {
spin_unlock_irqrestore(&bfqd->lock, flags);
return;
}
+ bfq_clear_bfqq_wait_request(bfqq);
+
if (bfq_bfqq_budget_timeout(bfqq))
/*
* Also here the queue can be safely expired
@@ -6273,7 +6279,7 @@ static enum hrtimer_restart bfq_idle_slice_timer(struct hrtimer *timer)
* early.
*/
if (bfqq)
- bfq_idle_slice_timer_body(bfqq);
+ bfq_idle_slice_timer_body(bfqd, bfqq);
return HRTIMER_NORESTART;
}
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index d1233af9c684..cd224aaf9f52 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -955,6 +955,7 @@ void bfq_bfqq_expire(struct bfq_data *bfqd, struct bfq_queue *bfqq,
bool compensate, enum bfqq_expiration reason);
void bfq_put_queue(struct bfq_queue *bfqq);
void bfq_end_wr_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg);
+void bfq_release_process_ref(struct bfq_data *bfqd, struct bfq_queue *bfqq);
void bfq_schedule_dispatch(struct bfq_data *bfqd);
void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg);
diff --git a/block/bio.c b/block/bio.c
index 94d697217887..21cbaa6a1c20 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -17,6 +17,7 @@
#include <linux/cgroup.h>
#include <linux/blk-cgroup.h>
#include <linux/highmem.h>
+#include <linux/sched/sysctl.h>
#include <trace/events/block.h>
#include "blk.h"
@@ -588,6 +589,49 @@ void bio_truncate(struct bio *bio, unsigned new_size)
}
/**
+ * guard_bio_eod - truncate a BIO to fit the block device
+ * @bio: bio to truncate
+ *
+ * This allows us to do IO even on the odd last sectors of a device, even if the
+ * block size is some multiple of the physical sector size.
+ *
+ * We'll just truncate the bio to the size of the device, and clear the end of
+ * the buffer head manually. Truly out-of-range accesses will turn into actual
+ * I/O errors, this only handles the "we need to be able to do I/O at the final
+ * sector" case.
+ */
+void guard_bio_eod(struct bio *bio)
+{
+ sector_t maxsector;
+ struct hd_struct *part;
+
+ rcu_read_lock();
+ part = __disk_get_part(bio->bi_disk, bio->bi_partno);
+ if (part)
+ maxsector = part_nr_sects_read(part);
+ else
+ maxsector = get_capacity(bio->bi_disk);
+ rcu_read_unlock();
+
+ if (!maxsector)
+ return;
+
+ /*
+ * If the *whole* IO is past the end of the device,
+ * let it through, and the IO layer will turn it into
+ * an EIO.
+ */
+ if (unlikely(bio->bi_iter.bi_sector >= maxsector))
+ return;
+
+ maxsector -= bio->bi_iter.bi_sector;
+ if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))
+ return;
+
+ bio_truncate(bio, maxsector << 9);
+}
+
+/**
* bio_put - release a reference to a bio
* @bio: bio to release reference to
*
@@ -679,6 +723,12 @@ struct bio *bio_clone_fast(struct bio *bio, gfp_t gfp_mask, struct bio_set *bs)
}
EXPORT_SYMBOL(bio_clone_fast);
+const char *bio_devname(struct bio *bio, char *buf)
+{
+ return disk_name(bio->bi_disk, bio->bi_partno, buf);
+}
+EXPORT_SYMBOL(bio_devname);
+
static inline bool page_is_mergeable(const struct bio_vec *bv,
struct page *page, unsigned int len, unsigned int off,
bool *same_page)
@@ -730,7 +780,7 @@ static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio,
*
* This should only be used by passthrough bios.
*/
-static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
+int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
struct page *page, unsigned int len, unsigned int offset,
bool *same_page)
{
@@ -1019,12 +1069,21 @@ static void submit_bio_wait_endio(struct bio *bio)
int submit_bio_wait(struct bio *bio)
{
DECLARE_COMPLETION_ONSTACK_MAP(done, bio->bi_disk->lockdep_map);
+ unsigned long hang_check;
bio->bi_private = &done;
bio->bi_end_io = submit_bio_wait_endio;
bio->bi_opf |= REQ_SYNC;
submit_bio(bio);
- wait_for_completion_io(&done);
+
+ /* Prevent hang_check timer from firing at us during very long I/O */
+ hang_check = sysctl_hung_task_timeout_secs;
+ if (hang_check)
+ while (!wait_for_completion_io_timeout(&done,
+ hang_check * (HZ/2)))
+ ;
+ else
+ wait_for_completion_io(&done);
return blk_status_to_errno(bio->bi_status);
}
@@ -1135,90 +1194,6 @@ void bio_list_copy_data(struct bio *dst, struct bio *src)
}
EXPORT_SYMBOL(bio_list_copy_data);
-struct bio_map_data {
- int is_our_pages;
- struct iov_iter iter;
- struct iovec iov[];
-};
-
-static struct bio_map_data *bio_alloc_map_data(struct iov_iter *data,
- gfp_t gfp_mask)
-{
- struct bio_map_data *bmd;
- if (data->nr_segs > UIO_MAXIOV)
- return NULL;
-
- bmd = kmalloc(struct_size(bmd, iov, data->nr_segs), gfp_mask);
- if (!bmd)
- return NULL;
- memcpy(bmd->iov, data->iov, sizeof(struct iovec) * data->nr_segs);
- bmd->iter = *data;
- bmd->iter.iov = bmd->iov;
- return bmd;
-}
-
-/**
- * bio_copy_from_iter - copy all pages from iov_iter to bio
- * @bio: The &struct bio which describes the I/O as destination
- * @iter: iov_iter as source
- *
- * Copy all pages from iov_iter to bio.
- * Returns 0 on success, or error on failure.
- */
-static int bio_copy_from_iter(struct bio *bio, struct iov_iter *iter)
-{
- struct bio_vec *bvec;
- struct bvec_iter_all iter_all;
-
- bio_for_each_segment_all(bvec, bio, iter_all) {
- ssize_t ret;
-
- ret = copy_page_from_iter(bvec->bv_page,
- bvec->bv_offset,
- bvec->bv_len,
- iter);
-
- if (!iov_iter_count(iter))
- break;
-
- if (ret < bvec->bv_len)
- return -EFAULT;
- }
-
- return 0;
-}
-
-/**
- * bio_copy_to_iter - copy all pages from bio to iov_iter
- * @bio: The &struct bio which describes the I/O as source
- * @iter: iov_iter as destination
- *
- * Copy all pages from bio to iov_iter.
- * Returns 0 on success, or error on failure.
- */
-static int bio_copy_to_iter(struct bio *bio, struct iov_iter iter)
-{
- struct bio_vec *bvec;
- struct bvec_iter_all iter_all;
-
- bio_for_each_segment_all(bvec, bio, iter_all) {
- ssize_t ret;
-
- ret = copy_page_to_iter(bvec->bv_page,
- bvec->bv_offset,
- bvec->bv_len,
- &iter);
-
- if (!iov_iter_count(&iter))
- break;
-
- if (ret < bvec->bv_len)
- return -EFAULT;
- }
-
- return 0;
-}
-
void bio_free_pages(struct bio *bio)
{
struct bio_vec *bvec;
@@ -1229,430 +1204,6 @@ void bio_free_pages(struct bio *bio)
}
EXPORT_SYMBOL(bio_free_pages);
-/**
- * bio_uncopy_user - finish previously mapped bio
- * @bio: bio being terminated
- *
- * Free pages allocated from bio_copy_user_iov() and write back data
- * to user space in case of a read.
- */
-int bio_uncopy_user(struct bio *bio)
-{
- struct bio_map_data *bmd = bio->bi_private;
- int ret = 0;
-
- if (!bio_flagged(bio, BIO_NULL_MAPPED)) {
- /*
- * if we're in a workqueue, the request is orphaned, so
- * don't copy into a random user address space, just free
- * and return -EINTR so user space doesn't expect any data.
- */
- if (!current->mm)
- ret = -EINTR;
- else if (bio_data_dir(bio) == READ)
- ret = bio_copy_to_iter(bio, bmd->iter);
- if (bmd->is_our_pages)
- bio_free_pages(bio);
- }
- kfree(bmd);
- bio_put(bio);
- return ret;
-}
-
-/**
- * bio_copy_user_iov - copy user data to bio
- * @q: destination block queue
- * @map_data: pointer to the rq_map_data holding pages (if necessary)
- * @iter: iovec iterator
- * @gfp_mask: memory allocation flags
- *
- * Prepares and returns a bio for indirect user io, bouncing data
- * to/from kernel pages as necessary. Must be paired with
- * call bio_uncopy_user() on io completion.
- */
-struct bio *bio_copy_user_iov(struct request_queue *q,
- struct rq_map_data *map_data,
- struct iov_iter *iter,
- gfp_t gfp_mask)
-{
- struct bio_map_data *bmd;
- struct page *page;
- struct bio *bio;
- int i = 0, ret;
- int nr_pages;
- unsigned int len = iter->count;
- unsigned int offset = map_data ? offset_in_page(map_data->offset) : 0;
-
- bmd = bio_alloc_map_data(iter, gfp_mask);
- if (!bmd)
- return ERR_PTR(-ENOMEM);
-
- /*
- * We need to do a deep copy of the iov_iter including the iovecs.
- * The caller provided iov might point to an on-stack or otherwise
- * shortlived one.
- */
- bmd->is_our_pages = map_data ? 0 : 1;
-
- nr_pages = DIV_ROUND_UP(offset + len, PAGE_SIZE);
- if (nr_pages > BIO_MAX_PAGES)
- nr_pages = BIO_MAX_PAGES;
-
- ret = -ENOMEM;
- bio = bio_kmalloc(gfp_mask, nr_pages);
- if (!bio)
- goto out_bmd;
-
- ret = 0;
-
- if (map_data) {
- nr_pages = 1 << map_data->page_order;
- i = map_data->offset / PAGE_SIZE;
- }
- while (len) {
- unsigned int bytes = PAGE_SIZE;
-
- bytes -= offset;
-
- if (bytes > len)
- bytes = len;
-
- if (map_data) {
- if (i == map_data->nr_entries * nr_pages) {
- ret = -ENOMEM;
- break;
- }
-
- page = map_data->pages[i / nr_pages];
- page += (i % nr_pages);
-
- i++;
- } else {
- page = alloc_page(q->bounce_gfp | gfp_mask);
- if (!page) {
- ret = -ENOMEM;
- break;
- }
- }
-
- if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes) {
- if (!map_data)
- __free_page(page);
- break;
- }
-
- len -= bytes;
- offset = 0;
- }
-
- if (ret)
- goto cleanup;
-
- if (map_data)
- map_data->offset += bio->bi_iter.bi_size;
-
- /*
- * success
- */
- if ((iov_iter_rw(iter) == WRITE && (!map_data || !map_data->null_mapped)) ||
- (map_data && map_data->from_user)) {
- ret = bio_copy_from_iter(bio, iter);
- if (ret)
- goto cleanup;
- } else {
- if (bmd->is_our_pages)
- zero_fill_bio(bio);
- iov_iter_advance(iter, bio->bi_iter.bi_size);
- }
-
- bio->bi_private = bmd;
- if (map_data && map_data->null_mapped)
- bio_set_flag(bio, BIO_NULL_MAPPED);
- return bio;
-cleanup:
- if (!map_data)
- bio_free_pages(bio);
- bio_put(bio);
-out_bmd:
- kfree(bmd);
- return ERR_PTR(ret);
-}
-
-/**
- * bio_map_user_iov - map user iovec into bio
- * @q: the struct request_queue for the bio
- * @iter: iovec iterator
- * @gfp_mask: memory allocation flags
- *
- * Map the user space address into a bio suitable for io to a block
- * device. Returns an error pointer in case of error.
- */
-struct bio *bio_map_user_iov(struct request_queue *q,
- struct iov_iter *iter,
- gfp_t gfp_mask)
-{
- int j;
- struct bio *bio;
- int ret;
-
- if (!iov_iter_count(iter))
- return ERR_PTR(-EINVAL);
-
- bio = bio_kmalloc(gfp_mask, iov_iter_npages(iter, BIO_MAX_PAGES));
- if (!bio)
- return ERR_PTR(-ENOMEM);
-
- while (iov_iter_count(iter)) {
- struct page **pages;
- ssize_t bytes;
- size_t offs, added = 0;
- int npages;
-
- bytes = iov_iter_get_pages_alloc(iter, &pages, LONG_MAX, &offs);
- if (unlikely(bytes <= 0)) {
- ret = bytes ? bytes : -EFAULT;
- goto out_unmap;
- }
-
- npages = DIV_ROUND_UP(offs + bytes, PAGE_SIZE);
-
- if (unlikely(offs & queue_dma_alignment(q))) {
- ret = -EINVAL;
- j = 0;
- } else {
- for (j = 0; j < npages; j++) {
- struct page *page = pages[j];
- unsigned int n = PAGE_SIZE - offs;
- bool same_page = false;
-
- if (n > bytes)
- n = bytes;
-
- if (!__bio_add_pc_page(q, bio, page, n, offs,
- &same_page)) {
- if (same_page)
- put_page(page);
- break;
- }
-
- added += n;
- bytes -= n;
- offs = 0;
- }
- iov_iter_advance(iter, added);
- }
- /*
- * release the pages we didn't map into the bio, if any
- */
- while (j < npages)
- put_page(pages[j++]);
- kvfree(pages);
- /* couldn't stuff something into bio? */
- if (bytes)
- break;
- }
-
- bio_set_flag(bio, BIO_USER_MAPPED);
-
- /*
- * subtle -- if bio_map_user_iov() ended up bouncing a bio,
- * it would normally disappear when its bi_end_io is run.
- * however, we need it for the unmap, so grab an extra
- * reference to it
- */
- bio_get(bio);
- return bio;
-
- out_unmap:
- bio_release_pages(bio, false);
- bio_put(bio);
- return ERR_PTR(ret);
-}
-
-/**
- * bio_unmap_user - unmap a bio
- * @bio: the bio being unmapped