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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/md/raid1.h
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
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ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/md/raid1.h')
-rw-r--r--drivers/md/raid1.h194
1 files changed, 194 insertions, 0 deletions
diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
new file mode 100644
index 000000000..c98d43a7a
--- /dev/null
+++ b/drivers/md/raid1.h
@@ -0,0 +1,194 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _RAID1_H
+#define _RAID1_H
+
+/*
+ * each barrier unit size is 64MB fow now
+ * note: it must be larger than RESYNC_DEPTH
+ */
+#define BARRIER_UNIT_SECTOR_BITS 17
+#define BARRIER_UNIT_SECTOR_SIZE (1<<17)
+/*
+ * In struct r1conf, the following members are related to I/O barrier
+ * buckets,
+ * atomic_t *nr_pending;
+ * atomic_t *nr_waiting;
+ * atomic_t *nr_queued;
+ * atomic_t *barrier;
+ * Each of them points to array of atomic_t variables, each array is
+ * designed to have BARRIER_BUCKETS_NR elements and occupy a single
+ * memory page. The data width of atomic_t variables is 4 bytes, equal
+ * to 1<<(ilog2(sizeof(atomic_t))), BARRIER_BUCKETS_NR_BITS is defined
+ * as (PAGE_SHIFT - ilog2(sizeof(int))) to make sure an array of
+ * atomic_t variables with BARRIER_BUCKETS_NR elements just exactly
+ * occupies a single memory page.
+ */
+#define BARRIER_BUCKETS_NR_BITS (PAGE_SHIFT - ilog2(sizeof(atomic_t)))
+#define BARRIER_BUCKETS_NR (1<<BARRIER_BUCKETS_NR_BITS)
+
+/* Note: raid1_info.rdev can be set to NULL asynchronously by raid1_remove_disk.
+ * There are three safe ways to access raid1_info.rdev.
+ * 1/ when holding mddev->reconfig_mutex
+ * 2/ when resync/recovery is known to be happening - i.e. in code that is
+ * called as part of performing resync/recovery.
+ * 3/ while holding rcu_read_lock(), use rcu_dereference to get the pointer
+ * and if it is non-NULL, increment rdev->nr_pending before dropping the
+ * RCU lock.
+ * When .rdev is set to NULL, the nr_pending count checked again and if it has
+ * been incremented, the pointer is put back in .rdev.
+ */
+
+struct raid1_info {
+ struct md_rdev *rdev;
+ sector_t head_position;
+
+ /* When choose the best device for a read (read_balance())
+ * we try to keep sequential reads one the same device
+ */
+ sector_t next_seq_sect;
+ sector_t seq_start;
+};
+
+struct r1conf {
+ struct mddev *mddev;
+ struct raid1_info *mirrors; /* twice 'raid_disks' to
+ * allow for replacements.
+ */
+ int raid_disks;
+ int nonrot_disks;
+
+ spinlock_t device_lock;
+
+ /* list of 'struct r1bio' that need to be processed by raid1d,
+ * whether to retry a read, writeout a resync or recovery
+ * block, or anything else.
+ */
+ struct list_head retry_list;
+ /* A separate list of r1bio which just need raid_end_bio_io called.
+ * This mustn't happen for writes which had any errors if the superblock
+ * needs to be written.
+ */
+ struct list_head bio_end_io_list;
+
+ /* queue pending writes to be submitted on unplug */
+ struct bio_list pending_bio_list;
+
+ /* for use when syncing mirrors:
+ * We don't allow both normal IO and resync/recovery IO at
+ * the same time - resync/recovery can only happen when there
+ * is no other IO. So when either is active, the other has to wait.
+ * See more details description in raid1.c near raise_barrier().
+ */
+ wait_queue_head_t wait_barrier;
+ spinlock_t resync_lock;
+ atomic_t nr_sync_pending;
+ atomic_t *nr_pending;
+ atomic_t *nr_waiting;
+ atomic_t *nr_queued;
+ atomic_t *barrier;
+ int array_frozen;
+
+ /* Set to 1 if a full sync is needed, (fresh device added).
+ * Cleared when a sync completes.
+ */
+ int fullsync;
+
+ mempool_t *r1bio_pool;
+ mempool_t r1buf_pool;
+
+ struct bio_set bio_split;
+
+ /* temporary buffer to synchronous IO when attempting to repair
+ * a read error.
+ */
+ struct page *tmppage;
+
+ /* When taking over an array from a different personality, we store
+ * the new thread here until we fully activate the array.
+ */
+ struct md_thread __rcu *thread;
+
+ /* Keep track of cluster resync window to send to other
+ * nodes.
+ */
+ sector_t cluster_sync_low;
+ sector_t cluster_sync_high;
+
+};
+
+/*
+ * this is our 'private' RAID1 bio.
+ *
+ * it contains information about what kind of IO operations were started
+ * for this RAID1 operation, and about their status:
+ */
+
+struct r1bio {
+ atomic_t remaining; /* 'have we finished' count,
+ * used from IRQ handlers
+ */
+ atomic_t behind_remaining; /* number of write-behind ios remaining
+ * in this BehindIO request
+ */
+ sector_t sector;
+ int sectors;
+ unsigned long state;
+ struct mddev *mddev;
+ /*
+ * original bio going to /dev/mdx
+ */
+ struct bio *master_bio;
+ /*
+ * if the IO is in READ direction, then this is where we read
+ */
+ int read_disk;
+
+ struct list_head retry_list;
+
+ /*
+ * When R1BIO_BehindIO is set, we store pages for write behind
+ * in behind_master_bio.
+ */
+ struct bio *behind_master_bio;
+
+ /*
+ * if the IO is in WRITE direction, then multiple bios are used.
+ * We choose the number when they are allocated.
+ */
+ struct bio *bios[];
+ /* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/
+};
+
+/* bits for r1bio.state */
+enum r1bio_state {
+ R1BIO_Uptodate,
+ R1BIO_IsSync,
+ R1BIO_BehindIO,
+/* Set ReadError on bios that experience a readerror so that
+ * raid1d knows what to do with them.
+ */
+ R1BIO_ReadError,
+/* For write-behind requests, we call bi_end_io when
+ * the last non-write-behind device completes, providing
+ * any write was successful. Otherwise we call when
+ * any write-behind write succeeds, otherwise we call
+ * with failure when last write completes (and all failed).
+ *
+ * And for bio_split errors, record that bi_end_io was called
+ * with this flag...
+ */
+ R1BIO_Returned,
+/* If a write for this request means we can clear some
+ * known-bad-block records, we set this flag
+ */
+ R1BIO_MadeGood,
+ R1BIO_WriteError,
+ R1BIO_FailFast,
+};
+
+static inline int sector_to_idx(sector_t sector)
+{
+ return hash_long(sector >> BARRIER_UNIT_SECTOR_BITS,
+ BARRIER_BUCKETS_NR_BITS);
+}
+#endif