#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"
}
EXPORT_SYMBOL(zero_fill_bio_iter);
+/**
+ * bio_truncate - truncate the bio to small size of @new_size
+ * @bio: the bio to be truncated
+ * @new_size: new size for truncating the bio
+ *
+ * Description:
+ * Truncate the bio to new size of @new_size. If bio_op(bio) is
+ * REQ_OP_READ, zero the truncated part. This function should only
+ * be used for handling corner cases, such as bio eod.
+ */
+void bio_truncate(struct bio *bio, unsigned new_size)
+{
+ struct bio_vec bv;
+ struct bvec_iter iter;
+ unsigned int done = 0;
+ bool truncated = false;
+
+ if (new_size >= bio->bi_iter.bi_size)
+ return;
+
+ if (bio_op(bio) != REQ_OP_READ)
+ goto exit;
+
+ bio_for_each_segment(bv, bio, iter) {
+ if (done + bv.bv_len > new_size) {
+ unsigned offset;
+
+ if (!truncated)
+ offset = new_size - done;
+ else
+ offset = 0;
+ zero_user(bv.bv_page, offset, bv.bv_len - offset);
+ truncated = true;
+ }
+ done += bv.bv_len;
+ }
+
+ exit:
+ /*
+ * Don't touch bvec table here and make it really immutable, since
+ * fs bio user has to retrieve all pages via bio_for_each_segment_all
+ * in its .end_bio() callback.
+ *
+ * It is enough to truncate bio by updating .bi_size since we can make
+ * correct bvec with the updated .bi_size for drivers.
+ */
+ bio->bi_iter.bi_size = 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
}
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)
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);
}
schedule_work(&bio_dirty_work);
}
-void update_io_ticks(struct hd_struct *part, unsigned long now)
+void update_io_ticks(struct hd_struct *part, unsigned long now, bool end)
{
unsigned long stamp;
again:
stamp = READ_ONCE(part->stamp);
if (unlikely(stamp != now)) {
if (likely(cmpxchg(&part->stamp, stamp, now) == stamp)) {
- __part_stat_add(part, io_ticks, 1);
+ __part_stat_add(part, io_ticks, end ? now - stamp : 1);
}
}
if (part->partno) {
part_stat_lock();
- update_io_ticks(part, jiffies);
+ update_io_ticks(part, jiffies, false);
part_stat_inc(part, ios[sgrp]);
part_stat_add(part, sectors[sgrp], sectors);
part_inc_in_flight(q, part, op_is_write(op));
part_stat_lock();
- update_io_ticks(part, now);
+ update_io_ticks(part, now, true);
part_stat_add(part, nsecs[sgrp], jiffies_to_nsecs(duration));
- part_stat_add(part, time_in_queue, duration);
part_dec_in_flight(q, part, op_is_write(req_op));
part_stat_unlock();
projects / mirror_ubuntu-jammy-kernel.git / blobdiff