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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/md/bcache/io.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/md/bcache/io.c')
-rw-r--r--drivers/md/bcache/io.c175
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c
new file mode 100644
index 000000000..020712c52
--- /dev/null
+++ b/drivers/md/bcache/io.c
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Some low level IO code, and hacks for various block layer limitations
+ *
+ * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
+ * Copyright 2012 Google, Inc.
+ */
+
+#include "bcache.h"
+#include "bset.h"
+#include "debug.h"
+
+#include <linux/blkdev.h>
+
+/* Bios with headers */
+
+void bch_bbio_free(struct bio *bio, struct cache_set *c)
+{
+ struct bbio *b = container_of(bio, struct bbio, bio);
+
+ mempool_free(b, &c->bio_meta);
+}
+
+struct bio *bch_bbio_alloc(struct cache_set *c)
+{
+ struct bbio *b = mempool_alloc(&c->bio_meta, GFP_NOIO);
+ struct bio *bio = &b->bio;
+
+ bio_init(bio, NULL, bio->bi_inline_vecs,
+ meta_bucket_pages(&c->cache->sb), 0);
+
+ return bio;
+}
+
+void __bch_submit_bbio(struct bio *bio, struct cache_set *c)
+{
+ struct bbio *b = container_of(bio, struct bbio, bio);
+
+ bio->bi_iter.bi_sector = PTR_OFFSET(&b->key, 0);
+ bio_set_dev(bio, c->cache->bdev);
+
+ b->submit_time_us = local_clock_us();
+ closure_bio_submit(c, bio, bio->bi_private);
+}
+
+void bch_submit_bbio(struct bio *bio, struct cache_set *c,
+ struct bkey *k, unsigned int ptr)
+{
+ struct bbio *b = container_of(bio, struct bbio, bio);
+
+ bch_bkey_copy_single_ptr(&b->key, k, ptr);
+ __bch_submit_bbio(bio, c);
+}
+
+/* IO errors */
+void bch_count_backing_io_errors(struct cached_dev *dc, struct bio *bio)
+{
+ unsigned int errors;
+
+ WARN_ONCE(!dc, "NULL pointer of struct cached_dev");
+
+ /*
+ * Read-ahead requests on a degrading and recovering md raid
+ * (e.g. raid6) device might be failured immediately by md
+ * raid code, which is not a real hardware media failure. So
+ * we shouldn't count failed REQ_RAHEAD bio to dc->io_errors.
+ */
+ if (bio->bi_opf & REQ_RAHEAD) {
+ pr_warn_ratelimited("%pg: Read-ahead I/O failed on backing device, ignore\n",
+ dc->bdev);
+ return;
+ }
+
+ errors = atomic_add_return(1, &dc->io_errors);
+ if (errors < dc->error_limit)
+ pr_err("%pg: IO error on backing device, unrecoverable\n",
+ dc->bdev);
+ else
+ bch_cached_dev_error(dc);
+}
+
+void bch_count_io_errors(struct cache *ca,
+ blk_status_t error,
+ int is_read,
+ const char *m)
+{
+ /*
+ * The halflife of an error is:
+ * log2(1/2)/log2(127/128) * refresh ~= 88 * refresh
+ */
+
+ if (ca->set->error_decay) {
+ unsigned int count = atomic_inc_return(&ca->io_count);
+
+ while (count > ca->set->error_decay) {
+ unsigned int errors;
+ unsigned int old = count;
+ unsigned int new = count - ca->set->error_decay;
+
+ /*
+ * First we subtract refresh from count; each time we
+ * successfully do so, we rescale the errors once:
+ */
+
+ count = atomic_cmpxchg(&ca->io_count, old, new);
+
+ if (count == old) {
+ count = new;
+
+ errors = atomic_read(&ca->io_errors);
+ do {
+ old = errors;
+ new = ((uint64_t) errors * 127) / 128;
+ errors = atomic_cmpxchg(&ca->io_errors,
+ old, new);
+ } while (old != errors);
+ }
+ }
+ }
+
+ if (error) {
+ unsigned int errors = atomic_add_return(1 << IO_ERROR_SHIFT,
+ &ca->io_errors);
+ errors >>= IO_ERROR_SHIFT;
+
+ if (errors < ca->set->error_limit)
+ pr_err("%pg: IO error on %s%s\n",
+ ca->bdev, m,
+ is_read ? ", recovering." : ".");
+ else
+ bch_cache_set_error(ca->set,
+ "%pg: too many IO errors %s\n",
+ ca->bdev, m);
+ }
+}
+
+void bch_bbio_count_io_errors(struct cache_set *c, struct bio *bio,
+ blk_status_t error, const char *m)
+{
+ struct bbio *b = container_of(bio, struct bbio, bio);
+ struct cache *ca = c->cache;
+ int is_read = (bio_data_dir(bio) == READ ? 1 : 0);
+
+ unsigned int threshold = op_is_write(bio_op(bio))
+ ? c->congested_write_threshold_us
+ : c->congested_read_threshold_us;
+
+ if (threshold) {
+ unsigned int t = local_clock_us();
+ int us = t - b->submit_time_us;
+ int congested = atomic_read(&c->congested);
+
+ if (us > (int) threshold) {
+ int ms = us / 1024;
+
+ c->congested_last_us = t;
+
+ ms = min(ms, CONGESTED_MAX + congested);
+ atomic_sub(ms, &c->congested);
+ } else if (congested < 0)
+ atomic_inc(&c->congested);
+ }
+
+ bch_count_io_errors(ca, error, is_read, m);
+}
+
+void bch_bbio_endio(struct cache_set *c, struct bio *bio,
+ blk_status_t error, const char *m)
+{
+ struct closure *cl = bio->bi_private;
+
+ bch_bbio_count_io_errors(c, bio, error, m);
+ bio_put(bio);
+ closure_put(cl);
+}