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![Song Liu](/assets/img/avatar_default.png)
write-back cache in degraded mode introduces corner cases to the array. Although we try to cover all these corner cases, it is safer to just disable write-back cache when the array is in degraded mode. In this patch, we disable writeback cache for degraded mode: 1. On device failure, if the array enters degraded mode, raid5_error() will submit async job r5c_disable_writeback_async to disable writeback; 2. In r5c_journal_mode_store(), it is invalid to enable writeback in degraded mode; 3. In r5c_try_caching_write(), stripes with s->failed>0 will be handled in write-through mode. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Shaohua Li <shli@fb.com>
2738 lines
74 KiB
C
2738 lines
74 KiB
C
/*
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* Copyright (C) 2015 Shaohua Li <shli@fb.com>
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* Copyright (C) 2016 Song Liu <songliubraving@fb.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms and conditions of the GNU General Public License,
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* version 2, as published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/wait.h>
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#include <linux/blkdev.h>
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#include <linux/slab.h>
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#include <linux/raid/md_p.h>
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#include <linux/crc32c.h>
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#include <linux/random.h>
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#include <linux/kthread.h>
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#include "md.h"
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#include "raid5.h"
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#include "bitmap.h"
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/*
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* metadata/data stored in disk with 4k size unit (a block) regardless
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* underneath hardware sector size. only works with PAGE_SIZE == 4096
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*/
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#define BLOCK_SECTORS (8)
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/*
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* log->max_free_space is min(1/4 disk size, 10G reclaimable space).
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*
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* In write through mode, the reclaim runs every log->max_free_space.
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* This can prevent the recovery scans for too long
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*/
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#define RECLAIM_MAX_FREE_SPACE (10 * 1024 * 1024 * 2) /* sector */
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#define RECLAIM_MAX_FREE_SPACE_SHIFT (2)
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/* wake up reclaim thread periodically */
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#define R5C_RECLAIM_WAKEUP_INTERVAL (30 * HZ)
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/* start flush with these full stripes */
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#define R5C_FULL_STRIPE_FLUSH_BATCH 256
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/* reclaim stripes in groups */
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#define R5C_RECLAIM_STRIPE_GROUP (NR_STRIPE_HASH_LOCKS * 2)
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/*
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* We only need 2 bios per I/O unit to make progress, but ensure we
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* have a few more available to not get too tight.
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*/
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#define R5L_POOL_SIZE 4
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/*
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* r5c journal modes of the array: write-back or write-through.
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* write-through mode has identical behavior as existing log only
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* implementation.
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*/
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enum r5c_journal_mode {
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R5C_JOURNAL_MODE_WRITE_THROUGH = 0,
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R5C_JOURNAL_MODE_WRITE_BACK = 1,
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};
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static char *r5c_journal_mode_str[] = {"write-through",
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"write-back"};
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/*
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* raid5 cache state machine
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*
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* With the RAID cache, each stripe works in two phases:
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* - caching phase
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* - writing-out phase
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*
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* These two phases are controlled by bit STRIPE_R5C_CACHING:
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* if STRIPE_R5C_CACHING == 0, the stripe is in writing-out phase
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* if STRIPE_R5C_CACHING == 1, the stripe is in caching phase
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*
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* When there is no journal, or the journal is in write-through mode,
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* the stripe is always in writing-out phase.
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*
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* For write-back journal, the stripe is sent to caching phase on write
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* (r5c_try_caching_write). r5c_make_stripe_write_out() kicks off
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* the write-out phase by clearing STRIPE_R5C_CACHING.
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*
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* Stripes in caching phase do not write the raid disks. Instead, all
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* writes are committed from the log device. Therefore, a stripe in
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* caching phase handles writes as:
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* - write to log device
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* - return IO
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*
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* Stripes in writing-out phase handle writes as:
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* - calculate parity
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* - write pending data and parity to journal
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* - write data and parity to raid disks
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* - return IO for pending writes
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*/
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struct r5l_log {
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struct md_rdev *rdev;
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u32 uuid_checksum;
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sector_t device_size; /* log device size, round to
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* BLOCK_SECTORS */
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sector_t max_free_space; /* reclaim run if free space is at
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* this size */
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sector_t last_checkpoint; /* log tail. where recovery scan
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* starts from */
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u64 last_cp_seq; /* log tail sequence */
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sector_t log_start; /* log head. where new data appends */
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u64 seq; /* log head sequence */
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sector_t next_checkpoint;
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struct mutex io_mutex;
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struct r5l_io_unit *current_io; /* current io_unit accepting new data */
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spinlock_t io_list_lock;
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struct list_head running_ios; /* io_units which are still running,
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* and have not yet been completely
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* written to the log */
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struct list_head io_end_ios; /* io_units which have been completely
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* written to the log but not yet written
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* to the RAID */
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struct list_head flushing_ios; /* io_units which are waiting for log
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* cache flush */
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struct list_head finished_ios; /* io_units which settle down in log disk */
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struct bio flush_bio;
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struct list_head no_mem_stripes; /* pending stripes, -ENOMEM */
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struct kmem_cache *io_kc;
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mempool_t *io_pool;
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struct bio_set *bs;
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mempool_t *meta_pool;
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struct md_thread *reclaim_thread;
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unsigned long reclaim_target; /* number of space that need to be
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* reclaimed. if it's 0, reclaim spaces
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* used by io_units which are in
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* IO_UNIT_STRIPE_END state (eg, reclaim
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* dones't wait for specific io_unit
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* switching to IO_UNIT_STRIPE_END
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* state) */
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wait_queue_head_t iounit_wait;
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struct list_head no_space_stripes; /* pending stripes, log has no space */
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spinlock_t no_space_stripes_lock;
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bool need_cache_flush;
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/* for r5c_cache */
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enum r5c_journal_mode r5c_journal_mode;
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/* all stripes in r5cache, in the order of seq at sh->log_start */
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struct list_head stripe_in_journal_list;
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spinlock_t stripe_in_journal_lock;
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atomic_t stripe_in_journal_count;
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/* to submit async io_units, to fulfill ordering of flush */
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struct work_struct deferred_io_work;
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/* to disable write back during in degraded mode */
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struct work_struct disable_writeback_work;
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};
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/*
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* an IO range starts from a meta data block and end at the next meta data
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* block. The io unit's the meta data block tracks data/parity followed it. io
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* unit is written to log disk with normal write, as we always flush log disk
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* first and then start move data to raid disks, there is no requirement to
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* write io unit with FLUSH/FUA
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*/
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struct r5l_io_unit {
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struct r5l_log *log;
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struct page *meta_page; /* store meta block */
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int meta_offset; /* current offset in meta_page */
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struct bio *current_bio;/* current_bio accepting new data */
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atomic_t pending_stripe;/* how many stripes not flushed to raid */
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u64 seq; /* seq number of the metablock */
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sector_t log_start; /* where the io_unit starts */
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sector_t log_end; /* where the io_unit ends */
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struct list_head log_sibling; /* log->running_ios */
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struct list_head stripe_list; /* stripes added to the io_unit */
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int state;
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bool need_split_bio;
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struct bio *split_bio;
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unsigned int has_flush:1; /* include flush request */
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unsigned int has_fua:1; /* include fua request */
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unsigned int has_null_flush:1; /* include empty flush request */
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/*
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* io isn't sent yet, flush/fua request can only be submitted till it's
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* the first IO in running_ios list
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*/
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unsigned int io_deferred:1;
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struct bio_list flush_barriers; /* size == 0 flush bios */
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};
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/* r5l_io_unit state */
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enum r5l_io_unit_state {
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IO_UNIT_RUNNING = 0, /* accepting new IO */
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IO_UNIT_IO_START = 1, /* io_unit bio start writing to log,
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* don't accepting new bio */
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IO_UNIT_IO_END = 2, /* io_unit bio finish writing to log */
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IO_UNIT_STRIPE_END = 3, /* stripes data finished writing to raid */
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};
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bool r5c_is_writeback(struct r5l_log *log)
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{
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return (log != NULL &&
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log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK);
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}
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static sector_t r5l_ring_add(struct r5l_log *log, sector_t start, sector_t inc)
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{
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start += inc;
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if (start >= log->device_size)
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start = start - log->device_size;
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return start;
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}
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static sector_t r5l_ring_distance(struct r5l_log *log, sector_t start,
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sector_t end)
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{
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if (end >= start)
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return end - start;
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else
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return end + log->device_size - start;
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}
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static bool r5l_has_free_space(struct r5l_log *log, sector_t size)
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{
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sector_t used_size;
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used_size = r5l_ring_distance(log, log->last_checkpoint,
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log->log_start);
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return log->device_size > used_size + size;
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}
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static void __r5l_set_io_unit_state(struct r5l_io_unit *io,
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enum r5l_io_unit_state state)
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{
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if (WARN_ON(io->state >= state))
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return;
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io->state = state;
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}
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static void
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r5c_return_dev_pending_writes(struct r5conf *conf, struct r5dev *dev,
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struct bio_list *return_bi)
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{
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struct bio *wbi, *wbi2;
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wbi = dev->written;
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dev->written = NULL;
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while (wbi && wbi->bi_iter.bi_sector <
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dev->sector + STRIPE_SECTORS) {
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wbi2 = r5_next_bio(wbi, dev->sector);
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if (!raid5_dec_bi_active_stripes(wbi)) {
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md_write_end(conf->mddev);
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bio_list_add(return_bi, wbi);
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}
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wbi = wbi2;
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}
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}
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void r5c_handle_cached_data_endio(struct r5conf *conf,
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struct stripe_head *sh, int disks, struct bio_list *return_bi)
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{
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int i;
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for (i = sh->disks; i--; ) {
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if (sh->dev[i].written) {
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set_bit(R5_UPTODATE, &sh->dev[i].flags);
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r5c_return_dev_pending_writes(conf, &sh->dev[i],
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return_bi);
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bitmap_endwrite(conf->mddev->bitmap, sh->sector,
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STRIPE_SECTORS,
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!test_bit(STRIPE_DEGRADED, &sh->state),
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0);
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}
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}
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}
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/* Check whether we should flush some stripes to free up stripe cache */
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void r5c_check_stripe_cache_usage(struct r5conf *conf)
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{
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int total_cached;
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if (!r5c_is_writeback(conf->log))
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return;
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total_cached = atomic_read(&conf->r5c_cached_partial_stripes) +
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atomic_read(&conf->r5c_cached_full_stripes);
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/*
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* The following condition is true for either of the following:
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* - stripe cache pressure high:
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* total_cached > 3/4 min_nr_stripes ||
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* empty_inactive_list_nr > 0
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* - stripe cache pressure moderate:
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* total_cached > 1/2 min_nr_stripes
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*/
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if (total_cached > conf->min_nr_stripes * 1 / 2 ||
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atomic_read(&conf->empty_inactive_list_nr) > 0)
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r5l_wake_reclaim(conf->log, 0);
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}
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/*
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* flush cache when there are R5C_FULL_STRIPE_FLUSH_BATCH or more full
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* stripes in the cache
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*/
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void r5c_check_cached_full_stripe(struct r5conf *conf)
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{
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if (!r5c_is_writeback(conf->log))
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return;
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/*
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* wake up reclaim for R5C_FULL_STRIPE_FLUSH_BATCH cached stripes
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* or a full stripe (chunk size / 4k stripes).
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*/
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if (atomic_read(&conf->r5c_cached_full_stripes) >=
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min(R5C_FULL_STRIPE_FLUSH_BATCH,
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conf->chunk_sectors >> STRIPE_SHIFT))
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r5l_wake_reclaim(conf->log, 0);
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}
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/*
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* Total log space (in sectors) needed to flush all data in cache
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*
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* Currently, writing-out phase automatically includes all pending writes
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* to the same sector. So the reclaim of each stripe takes up to
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* (conf->raid_disks + 1) pages of log space.
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*
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* To totally avoid deadlock due to log space, the code reserves
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* (conf->raid_disks + 1) pages for each stripe in cache, which is not
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* necessary in most cases.
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*
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* To improve this, we will need writing-out phase to be able to NOT include
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* pending writes, which will reduce the requirement to
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* (conf->max_degraded + 1) pages per stripe in cache.
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*/
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static sector_t r5c_log_required_to_flush_cache(struct r5conf *conf)
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{
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struct r5l_log *log = conf->log;
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if (!r5c_is_writeback(log))
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return 0;
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return BLOCK_SECTORS * (conf->raid_disks + 1) *
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atomic_read(&log->stripe_in_journal_count);
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}
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/*
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* evaluate log space usage and update R5C_LOG_TIGHT and R5C_LOG_CRITICAL
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*
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* R5C_LOG_TIGHT is set when free space on the log device is less than 3x of
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* reclaim_required_space. R5C_LOG_CRITICAL is set when free space on the log
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* device is less than 2x of reclaim_required_space.
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*/
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static inline void r5c_update_log_state(struct r5l_log *log)
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{
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struct r5conf *conf = log->rdev->mddev->private;
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sector_t free_space;
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sector_t reclaim_space;
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bool wake_reclaim = false;
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if (!r5c_is_writeback(log))
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return;
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free_space = r5l_ring_distance(log, log->log_start,
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log->last_checkpoint);
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reclaim_space = r5c_log_required_to_flush_cache(conf);
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if (free_space < 2 * reclaim_space)
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set_bit(R5C_LOG_CRITICAL, &conf->cache_state);
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else {
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if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state))
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wake_reclaim = true;
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clear_bit(R5C_LOG_CRITICAL, &conf->cache_state);
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}
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if (free_space < 3 * reclaim_space)
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set_bit(R5C_LOG_TIGHT, &conf->cache_state);
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else
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clear_bit(R5C_LOG_TIGHT, &conf->cache_state);
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if (wake_reclaim)
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r5l_wake_reclaim(log, 0);
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}
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/*
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* Put the stripe into writing-out phase by clearing STRIPE_R5C_CACHING.
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* This function should only be called in write-back mode.
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*/
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void r5c_make_stripe_write_out(struct stripe_head *sh)
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{
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struct r5conf *conf = sh->raid_conf;
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struct r5l_log *log = conf->log;
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BUG_ON(!r5c_is_writeback(log));
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WARN_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state));
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clear_bit(STRIPE_R5C_CACHING, &sh->state);
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if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
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atomic_inc(&conf->preread_active_stripes);
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if (test_and_clear_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) {
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BUG_ON(atomic_read(&conf->r5c_cached_partial_stripes) == 0);
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atomic_dec(&conf->r5c_cached_partial_stripes);
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}
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if (test_and_clear_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) {
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BUG_ON(atomic_read(&conf->r5c_cached_full_stripes) == 0);
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atomic_dec(&conf->r5c_cached_full_stripes);
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}
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}
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static void r5c_handle_data_cached(struct stripe_head *sh)
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{
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int i;
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for (i = sh->disks; i--; )
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if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) {
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set_bit(R5_InJournal, &sh->dev[i].flags);
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clear_bit(R5_LOCKED, &sh->dev[i].flags);
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}
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clear_bit(STRIPE_LOG_TRAPPED, &sh->state);
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}
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/*
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* this journal write must contain full parity,
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* it may also contain some data pages
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*/
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static void r5c_handle_parity_cached(struct stripe_head *sh)
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{
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int i;
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for (i = sh->disks; i--; )
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if (test_bit(R5_InJournal, &sh->dev[i].flags))
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set_bit(R5_Wantwrite, &sh->dev[i].flags);
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}
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/*
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* Setting proper flags after writing (or flushing) data and/or parity to the
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* log device. This is called from r5l_log_endio() or r5l_log_flush_endio().
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*/
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static void r5c_finish_cache_stripe(struct stripe_head *sh)
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{
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struct r5l_log *log = sh->raid_conf->log;
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if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) {
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BUG_ON(test_bit(STRIPE_R5C_CACHING, &sh->state));
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/*
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* Set R5_InJournal for parity dev[pd_idx]. This means
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* all data AND parity in the journal. For RAID 6, it is
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* NOT necessary to set the flag for dev[qd_idx], as the
|
|
* two parities are written out together.
|
|
*/
|
|
set_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags);
|
|
} else if (test_bit(STRIPE_R5C_CACHING, &sh->state)) {
|
|
r5c_handle_data_cached(sh);
|
|
} else {
|
|
r5c_handle_parity_cached(sh);
|
|
set_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags);
|
|
}
|
|
}
|
|
|
|
static void r5l_io_run_stripes(struct r5l_io_unit *io)
|
|
{
|
|
struct stripe_head *sh, *next;
|
|
|
|
list_for_each_entry_safe(sh, next, &io->stripe_list, log_list) {
|
|
list_del_init(&sh->log_list);
|
|
|
|
r5c_finish_cache_stripe(sh);
|
|
|
|
set_bit(STRIPE_HANDLE, &sh->state);
|
|
raid5_release_stripe(sh);
|
|
}
|
|
}
|
|
|
|
static void r5l_log_run_stripes(struct r5l_log *log)
|
|
{
|
|
struct r5l_io_unit *io, *next;
|
|
|
|
assert_spin_locked(&log->io_list_lock);
|
|
|
|
list_for_each_entry_safe(io, next, &log->running_ios, log_sibling) {
|
|
/* don't change list order */
|
|
if (io->state < IO_UNIT_IO_END)
|
|
break;
|
|
|
|
list_move_tail(&io->log_sibling, &log->finished_ios);
|
|
r5l_io_run_stripes(io);
|
|
}
|
|
}
|
|
|
|
static void r5l_move_to_end_ios(struct r5l_log *log)
|
|
{
|
|
struct r5l_io_unit *io, *next;
|
|
|
|
assert_spin_locked(&log->io_list_lock);
|
|
|
|
list_for_each_entry_safe(io, next, &log->running_ios, log_sibling) {
|
|
/* don't change list order */
|
|
if (io->state < IO_UNIT_IO_END)
|
|
break;
|
|
list_move_tail(&io->log_sibling, &log->io_end_ios);
|
|
}
|
|
}
|
|
|
|
static void __r5l_stripe_write_finished(struct r5l_io_unit *io);
|
|
static void r5l_log_endio(struct bio *bio)
|
|
{
|
|
struct r5l_io_unit *io = bio->bi_private;
|
|
struct r5l_io_unit *io_deferred;
|
|
struct r5l_log *log = io->log;
|
|
unsigned long flags;
|
|
|
|
if (bio->bi_error)
|
|
md_error(log->rdev->mddev, log->rdev);
|
|
|
|
bio_put(bio);
|
|
mempool_free(io->meta_page, log->meta_pool);
|
|
|
|
spin_lock_irqsave(&log->io_list_lock, flags);
|
|
__r5l_set_io_unit_state(io, IO_UNIT_IO_END);
|
|
if (log->need_cache_flush)
|
|
r5l_move_to_end_ios(log);
|
|
else
|
|
r5l_log_run_stripes(log);
|
|
if (!list_empty(&log->running_ios)) {
|
|
/*
|
|
* FLUSH/FUA io_unit is deferred because of ordering, now we
|
|
* can dispatch it
|
|
*/
|
|
io_deferred = list_first_entry(&log->running_ios,
|
|
struct r5l_io_unit, log_sibling);
|
|
if (io_deferred->io_deferred)
|
|
schedule_work(&log->deferred_io_work);
|
|
}
|
|
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
|
|
if (log->need_cache_flush)
|
|
md_wakeup_thread(log->rdev->mddev->thread);
|
|
|
|
if (io->has_null_flush) {
|
|
struct bio *bi;
|
|
|
|
WARN_ON(bio_list_empty(&io->flush_barriers));
|
|
while ((bi = bio_list_pop(&io->flush_barriers)) != NULL) {
|
|
bio_endio(bi);
|
|
atomic_dec(&io->pending_stripe);
|
|
}
|
|
if (atomic_read(&io->pending_stripe) == 0)
|
|
__r5l_stripe_write_finished(io);
|
|
}
|
|
}
|
|
|
|
static void r5l_do_submit_io(struct r5l_log *log, struct r5l_io_unit *io)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&log->io_list_lock, flags);
|
|
__r5l_set_io_unit_state(io, IO_UNIT_IO_START);
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
|
|
if (io->has_flush)
|
|
io->current_bio->bi_opf |= REQ_PREFLUSH;
|
|
if (io->has_fua)
|
|
io->current_bio->bi_opf |= REQ_FUA;
|
|
submit_bio(io->current_bio);
|
|
|
|
if (!io->split_bio)
|
|
return;
|
|
|
|
if (io->has_flush)
|
|
io->split_bio->bi_opf |= REQ_PREFLUSH;
|
|
if (io->has_fua)
|
|
io->split_bio->bi_opf |= REQ_FUA;
|
|
submit_bio(io->split_bio);
|
|
}
|
|
|
|
/* deferred io_unit will be dispatched here */
|
|
static void r5l_submit_io_async(struct work_struct *work)
|
|
{
|
|
struct r5l_log *log = container_of(work, struct r5l_log,
|
|
deferred_io_work);
|
|
struct r5l_io_unit *io = NULL;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&log->io_list_lock, flags);
|
|
if (!list_empty(&log->running_ios)) {
|
|
io = list_first_entry(&log->running_ios, struct r5l_io_unit,
|
|
log_sibling);
|
|
if (!io->io_deferred)
|
|
io = NULL;
|
|
else
|
|
io->io_deferred = 0;
|
|
}
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
if (io)
|
|
r5l_do_submit_io(log, io);
|
|
}
|
|
|
|
static void r5c_disable_writeback_async(struct work_struct *work)
|
|
{
|
|
struct r5l_log *log = container_of(work, struct r5l_log,
|
|
disable_writeback_work);
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
|
|
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
|
|
return;
|
|
pr_info("md/raid:%s: Disabling writeback cache for degraded array.\n",
|
|
mdname(mddev));
|
|
mddev_suspend(mddev);
|
|
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
|
|
mddev_resume(mddev);
|
|
}
|
|
|
|
static void r5l_submit_current_io(struct r5l_log *log)
|
|
{
|
|
struct r5l_io_unit *io = log->current_io;
|
|
struct bio *bio;
|
|
struct r5l_meta_block *block;
|
|
unsigned long flags;
|
|
u32 crc;
|
|
bool do_submit = true;
|
|
|
|
if (!io)
|
|
return;
|
|
|
|
block = page_address(io->meta_page);
|
|
block->meta_size = cpu_to_le32(io->meta_offset);
|
|
crc = crc32c_le(log->uuid_checksum, block, PAGE_SIZE);
|
|
block->checksum = cpu_to_le32(crc);
|
|
bio = io->current_bio;
|
|
|
|
log->current_io = NULL;
|
|
spin_lock_irqsave(&log->io_list_lock, flags);
|
|
if (io->has_flush || io->has_fua) {
|
|
if (io != list_first_entry(&log->running_ios,
|
|
struct r5l_io_unit, log_sibling)) {
|
|
io->io_deferred = 1;
|
|
do_submit = false;
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
if (do_submit)
|
|
r5l_do_submit_io(log, io);
|
|
}
|
|
|
|
static struct bio *r5l_bio_alloc(struct r5l_log *log)
|
|
{
|
|
struct bio *bio = bio_alloc_bioset(GFP_NOIO, BIO_MAX_PAGES, log->bs);
|
|
|
|
bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
|
|
bio->bi_bdev = log->rdev->bdev;
|
|
bio->bi_iter.bi_sector = log->rdev->data_offset + log->log_start;
|
|
|
|
return bio;
|
|
}
|
|
|
|
static void r5_reserve_log_entry(struct r5l_log *log, struct r5l_io_unit *io)
|
|
{
|
|
log->log_start = r5l_ring_add(log, log->log_start, BLOCK_SECTORS);
|
|
|
|
r5c_update_log_state(log);
|
|
/*
|
|
* If we filled up the log device start from the beginning again,
|
|
* which will require a new bio.
|
|
*
|
|
* Note: for this to work properly the log size needs to me a multiple
|
|
* of BLOCK_SECTORS.
|
|
*/
|
|
if (log->log_start == 0)
|
|
io->need_split_bio = true;
|
|
|
|
io->log_end = log->log_start;
|
|
}
|
|
|
|
static struct r5l_io_unit *r5l_new_meta(struct r5l_log *log)
|
|
{
|
|
struct r5l_io_unit *io;
|
|
struct r5l_meta_block *block;
|
|
|
|
io = mempool_alloc(log->io_pool, GFP_ATOMIC);
|
|
if (!io)
|
|
return NULL;
|
|
memset(io, 0, sizeof(*io));
|
|
|
|
io->log = log;
|
|
INIT_LIST_HEAD(&io->log_sibling);
|
|
INIT_LIST_HEAD(&io->stripe_list);
|
|
bio_list_init(&io->flush_barriers);
|
|
io->state = IO_UNIT_RUNNING;
|
|
|
|
io->meta_page = mempool_alloc(log->meta_pool, GFP_NOIO);
|
|
block = page_address(io->meta_page);
|
|
clear_page(block);
|
|
block->magic = cpu_to_le32(R5LOG_MAGIC);
|
|
block->version = R5LOG_VERSION;
|
|
block->seq = cpu_to_le64(log->seq);
|
|
block->position = cpu_to_le64(log->log_start);
|
|
|
|
io->log_start = log->log_start;
|
|
io->meta_offset = sizeof(struct r5l_meta_block);
|
|
io->seq = log->seq++;
|
|
|
|
io->current_bio = r5l_bio_alloc(log);
|
|
io->current_bio->bi_end_io = r5l_log_endio;
|
|
io->current_bio->bi_private = io;
|
|
bio_add_page(io->current_bio, io->meta_page, PAGE_SIZE, 0);
|
|
|
|
r5_reserve_log_entry(log, io);
|
|
|
|
spin_lock_irq(&log->io_list_lock);
|
|
list_add_tail(&io->log_sibling, &log->running_ios);
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
|
|
return io;
|
|
}
|
|
|
|
static int r5l_get_meta(struct r5l_log *log, unsigned int payload_size)
|
|
{
|
|
if (log->current_io &&
|
|
log->current_io->meta_offset + payload_size > PAGE_SIZE)
|
|
r5l_submit_current_io(log);
|
|
|
|
if (!log->current_io) {
|
|
log->current_io = r5l_new_meta(log);
|
|
if (!log->current_io)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void r5l_append_payload_meta(struct r5l_log *log, u16 type,
|
|
sector_t location,
|
|
u32 checksum1, u32 checksum2,
|
|
bool checksum2_valid)
|
|
{
|
|
struct r5l_io_unit *io = log->current_io;
|
|
struct r5l_payload_data_parity *payload;
|
|
|
|
payload = page_address(io->meta_page) + io->meta_offset;
|
|
payload->header.type = cpu_to_le16(type);
|
|
payload->header.flags = cpu_to_le16(0);
|
|
payload->size = cpu_to_le32((1 + !!checksum2_valid) <<
|
|
(PAGE_SHIFT - 9));
|
|
payload->location = cpu_to_le64(location);
|
|
payload->checksum[0] = cpu_to_le32(checksum1);
|
|
if (checksum2_valid)
|
|
payload->checksum[1] = cpu_to_le32(checksum2);
|
|
|
|
io->meta_offset += sizeof(struct r5l_payload_data_parity) +
|
|
sizeof(__le32) * (1 + !!checksum2_valid);
|
|
}
|
|
|
|
static void r5l_append_payload_page(struct r5l_log *log, struct page *page)
|
|
{
|
|
struct r5l_io_unit *io = log->current_io;
|
|
|
|
if (io->need_split_bio) {
|
|
BUG_ON(io->split_bio);
|
|
io->split_bio = io->current_bio;
|
|
io->current_bio = r5l_bio_alloc(log);
|
|
bio_chain(io->current_bio, io->split_bio);
|
|
io->need_split_bio = false;
|
|
}
|
|
|
|
if (!bio_add_page(io->current_bio, page, PAGE_SIZE, 0))
|
|
BUG();
|
|
|
|
r5_reserve_log_entry(log, io);
|
|
}
|
|
|
|
static int r5l_log_stripe(struct r5l_log *log, struct stripe_head *sh,
|
|
int data_pages, int parity_pages)
|
|
{
|
|
int i;
|
|
int meta_size;
|
|
int ret;
|
|
struct r5l_io_unit *io;
|
|
|
|
meta_size =
|
|
((sizeof(struct r5l_payload_data_parity) + sizeof(__le32))
|
|
* data_pages) +
|
|
sizeof(struct r5l_payload_data_parity) +
|
|
sizeof(__le32) * parity_pages;
|
|
|
|
ret = r5l_get_meta(log, meta_size);
|
|
if (ret)
|
|
return ret;
|
|
|
|
io = log->current_io;
|
|
|
|
if (test_and_clear_bit(STRIPE_R5C_PREFLUSH, &sh->state))
|
|
io->has_flush = 1;
|
|
|
|
for (i = 0; i < sh->disks; i++) {
|
|
if (!test_bit(R5_Wantwrite, &sh->dev[i].flags) ||
|
|
test_bit(R5_InJournal, &sh->dev[i].flags))
|
|
continue;
|
|
if (i == sh->pd_idx || i == sh->qd_idx)
|
|
continue;
|
|
if (test_bit(R5_WantFUA, &sh->dev[i].flags) &&
|
|
log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK) {
|
|
io->has_fua = 1;
|
|
/*
|
|
* we need to flush journal to make sure recovery can
|
|
* reach the data with fua flag
|
|
*/
|
|
io->has_flush = 1;
|
|
}
|
|
r5l_append_payload_meta(log, R5LOG_PAYLOAD_DATA,
|
|
raid5_compute_blocknr(sh, i, 0),
|
|
sh->dev[i].log_checksum, 0, false);
|
|
r5l_append_payload_page(log, sh->dev[i].page);
|
|
}
|
|
|
|
if (parity_pages == 2) {
|
|
r5l_append_payload_meta(log, R5LOG_PAYLOAD_PARITY,
|
|
sh->sector, sh->dev[sh->pd_idx].log_checksum,
|
|
sh->dev[sh->qd_idx].log_checksum, true);
|
|
r5l_append_payload_page(log, sh->dev[sh->pd_idx].page);
|
|
r5l_append_payload_page(log, sh->dev[sh->qd_idx].page);
|
|
} else if (parity_pages == 1) {
|
|
r5l_append_payload_meta(log, R5LOG_PAYLOAD_PARITY,
|
|
sh->sector, sh->dev[sh->pd_idx].log_checksum,
|
|
0, false);
|
|
r5l_append_payload_page(log, sh->dev[sh->pd_idx].page);
|
|
} else /* Just writing data, not parity, in caching phase */
|
|
BUG_ON(parity_pages != 0);
|
|
|
|
list_add_tail(&sh->log_list, &io->stripe_list);
|
|
atomic_inc(&io->pending_stripe);
|
|
sh->log_io = io;
|
|
|
|
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
|
|
return 0;
|
|
|
|
if (sh->log_start == MaxSector) {
|
|
BUG_ON(!list_empty(&sh->r5c));
|
|
sh->log_start = io->log_start;
|
|
spin_lock_irq(&log->stripe_in_journal_lock);
|
|
list_add_tail(&sh->r5c,
|
|
&log->stripe_in_journal_list);
|
|
spin_unlock_irq(&log->stripe_in_journal_lock);
|
|
atomic_inc(&log->stripe_in_journal_count);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* add stripe to no_space_stripes, and then wake up reclaim */
|
|
static inline void r5l_add_no_space_stripe(struct r5l_log *log,
|
|
struct stripe_head *sh)
|
|
{
|
|
spin_lock(&log->no_space_stripes_lock);
|
|
list_add_tail(&sh->log_list, &log->no_space_stripes);
|
|
spin_unlock(&log->no_space_stripes_lock);
|
|
}
|
|
|
|
/*
|
|
* running in raid5d, where reclaim could wait for raid5d too (when it flushes
|
|
* data from log to raid disks), so we shouldn't wait for reclaim here
|
|
*/
|
|
int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
|
|
{
|
|
struct r5conf *conf = sh->raid_conf;
|
|
int write_disks = 0;
|
|
int data_pages, parity_pages;
|
|
int reserve;
|
|
int i;
|
|
int ret = 0;
|
|
bool wake_reclaim = false;
|
|
|
|
if (!log)
|
|
return -EAGAIN;
|
|
/* Don't support stripe batch */
|
|
if (sh->log_io || !test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags) ||
|
|
test_bit(STRIPE_SYNCING, &sh->state)) {
|
|
/* the stripe is written to log, we start writing it to raid */
|
|
clear_bit(STRIPE_LOG_TRAPPED, &sh->state);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state));
|
|
|
|
for (i = 0; i < sh->disks; i++) {
|
|
void *addr;
|
|
|
|
if (!test_bit(R5_Wantwrite, &sh->dev[i].flags) ||
|
|
test_bit(R5_InJournal, &sh->dev[i].flags))
|
|
continue;
|
|
|
|
write_disks++;
|
|
/* checksum is already calculated in last run */
|
|
if (test_bit(STRIPE_LOG_TRAPPED, &sh->state))
|
|
continue;
|
|
addr = kmap_atomic(sh->dev[i].page);
|
|
sh->dev[i].log_checksum = crc32c_le(log->uuid_checksum,
|
|
addr, PAGE_SIZE);
|
|
kunmap_atomic(addr);
|
|
}
|
|
parity_pages = 1 + !!(sh->qd_idx >= 0);
|
|
data_pages = write_disks - parity_pages;
|
|
|
|
set_bit(STRIPE_LOG_TRAPPED, &sh->state);
|
|
/*
|
|
* The stripe must enter state machine again to finish the write, so
|
|
* don't delay.
|
|
*/
|
|
clear_bit(STRIPE_DELAYED, &sh->state);
|
|
atomic_inc(&sh->count);
|
|
|
|
mutex_lock(&log->io_mutex);
|
|
/* meta + data */
|
|
reserve = (1 + write_disks) << (PAGE_SHIFT - 9);
|
|
|
|
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) {
|
|
if (!r5l_has_free_space(log, reserve)) {
|
|
r5l_add_no_space_stripe(log, sh);
|
|
wake_reclaim = true;
|
|
} else {
|
|
ret = r5l_log_stripe(log, sh, data_pages, parity_pages);
|
|
if (ret) {
|
|
spin_lock_irq(&log->io_list_lock);
|
|
list_add_tail(&sh->log_list,
|
|
&log->no_mem_stripes);
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
}
|
|
}
|
|
} else { /* R5C_JOURNAL_MODE_WRITE_BACK */
|
|
/*
|
|
* log space critical, do not process stripes that are
|
|
* not in cache yet (sh->log_start == MaxSector).
|
|
*/
|
|
if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) &&
|
|
sh->log_start == MaxSector) {
|
|
r5l_add_no_space_stripe(log, sh);
|
|
wake_reclaim = true;
|
|
reserve = 0;
|
|
} else if (!r5l_has_free_space(log, reserve)) {
|
|
if (sh->log_start == log->last_checkpoint)
|
|
BUG();
|
|
else
|
|
r5l_add_no_space_stripe(log, sh);
|
|
} else {
|
|
ret = r5l_log_stripe(log, sh, data_pages, parity_pages);
|
|
if (ret) {
|
|
spin_lock_irq(&log->io_list_lock);
|
|
list_add_tail(&sh->log_list,
|
|
&log->no_mem_stripes);
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
}
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&log->io_mutex);
|
|
if (wake_reclaim)
|
|
r5l_wake_reclaim(log, reserve);
|
|
return 0;
|
|
}
|
|
|
|
void r5l_write_stripe_run(struct r5l_log *log)
|
|
{
|
|
if (!log)
|
|
return;
|
|
mutex_lock(&log->io_mutex);
|
|
r5l_submit_current_io(log);
|
|
mutex_unlock(&log->io_mutex);
|
|
}
|
|
|
|
int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio)
|
|
{
|
|
if (!log)
|
|
return -ENODEV;
|
|
|
|
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) {
|
|
/*
|
|
* in write through (journal only)
|
|
* we flush log disk cache first, then write stripe data to
|
|
* raid disks. So if bio is finished, the log disk cache is
|
|
* flushed already. The recovery guarantees we can recovery
|
|
* the bio from log disk, so we don't need to flush again
|
|
*/
|
|
if (bio->bi_iter.bi_size == 0) {
|
|
bio_endio(bio);
|
|
return 0;
|
|
}
|
|
bio->bi_opf &= ~REQ_PREFLUSH;
|
|
} else {
|
|
/* write back (with cache) */
|
|
if (bio->bi_iter.bi_size == 0) {
|
|
mutex_lock(&log->io_mutex);
|
|
r5l_get_meta(log, 0);
|
|
bio_list_add(&log->current_io->flush_barriers, bio);
|
|
log->current_io->has_flush = 1;
|
|
log->current_io->has_null_flush = 1;
|
|
atomic_inc(&log->current_io->pending_stripe);
|
|
r5l_submit_current_io(log);
|
|
mutex_unlock(&log->io_mutex);
|
|
return 0;
|
|
}
|
|
}
|
|
return -EAGAIN;
|
|
}
|
|
|
|
/* This will run after log space is reclaimed */
|
|
static void r5l_run_no_space_stripes(struct r5l_log *log)
|
|
{
|
|
struct stripe_head *sh;
|
|
|
|
spin_lock(&log->no_space_stripes_lock);
|
|
while (!list_empty(&log->no_space_stripes)) {
|
|
sh = list_first_entry(&log->no_space_stripes,
|
|
struct stripe_head, log_list);
|
|
list_del_init(&sh->log_list);
|
|
set_bit(STRIPE_HANDLE, &sh->state);
|
|
raid5_release_stripe(sh);
|
|
}
|
|
spin_unlock(&log->no_space_stripes_lock);
|
|
}
|
|
|
|
/*
|
|
* calculate new last_checkpoint
|
|
* for write through mode, returns log->next_checkpoint
|
|
* for write back, returns log_start of first sh in stripe_in_journal_list
|
|
*/
|
|
static sector_t r5c_calculate_new_cp(struct r5conf *conf)
|
|
{
|
|
struct stripe_head *sh;
|
|
struct r5l_log *log = conf->log;
|
|
sector_t new_cp;
|
|
unsigned long flags;
|
|
|
|
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
|
|
return log->next_checkpoint;
|
|
|
|
spin_lock_irqsave(&log->stripe_in_journal_lock, flags);
|
|
if (list_empty(&conf->log->stripe_in_journal_list)) {
|
|
/* all stripes flushed */
|
|
spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags);
|
|
return log->next_checkpoint;
|
|
}
|
|
sh = list_first_entry(&conf->log->stripe_in_journal_list,
|
|
struct stripe_head, r5c);
|
|
new_cp = sh->log_start;
|
|
spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags);
|
|
return new_cp;
|
|
}
|
|
|
|
static sector_t r5l_reclaimable_space(struct r5l_log *log)
|
|
{
|
|
struct r5conf *conf = log->rdev->mddev->private;
|
|
|
|
return r5l_ring_distance(log, log->last_checkpoint,
|
|
r5c_calculate_new_cp(conf));
|
|
}
|
|
|
|
static void r5l_run_no_mem_stripe(struct r5l_log *log)
|
|
{
|
|
struct stripe_head *sh;
|
|
|
|
assert_spin_locked(&log->io_list_lock);
|
|
|
|
if (!list_empty(&log->no_mem_stripes)) {
|
|
sh = list_first_entry(&log->no_mem_stripes,
|
|
struct stripe_head, log_list);
|
|
list_del_init(&sh->log_list);
|
|
set_bit(STRIPE_HANDLE, &sh->state);
|
|
raid5_release_stripe(sh);
|
|
}
|
|
}
|
|
|
|
static bool r5l_complete_finished_ios(struct r5l_log *log)
|
|
{
|
|
struct r5l_io_unit *io, *next;
|
|
bool found = false;
|
|
|
|
assert_spin_locked(&log->io_list_lock);
|
|
|
|
list_for_each_entry_safe(io, next, &log->finished_ios, log_sibling) {
|
|
/* don't change list order */
|
|
if (io->state < IO_UNIT_STRIPE_END)
|
|
break;
|
|
|
|
log->next_checkpoint = io->log_start;
|
|
|
|
list_del(&io->log_sibling);
|
|
mempool_free(io, log->io_pool);
|
|
r5l_run_no_mem_stripe(log);
|
|
|
|
found = true;
|
|
}
|
|
|
|
return found;
|
|
}
|
|
|
|
static void __r5l_stripe_write_finished(struct r5l_io_unit *io)
|
|
{
|
|
struct r5l_log *log = io->log;
|
|
struct r5conf *conf = log->rdev->mddev->private;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&log->io_list_lock, flags);
|
|
__r5l_set_io_unit_state(io, IO_UNIT_STRIPE_END);
|
|
|
|
if (!r5l_complete_finished_ios(log)) {
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
return;
|
|
}
|
|
|
|
if (r5l_reclaimable_space(log) > log->max_free_space ||
|
|
test_bit(R5C_LOG_TIGHT, &conf->cache_state))
|
|
r5l_wake_reclaim(log, 0);
|
|
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
wake_up(&log->iounit_wait);
|
|
}
|
|
|
|
void r5l_stripe_write_finished(struct stripe_head *sh)
|
|
{
|
|
struct r5l_io_unit *io;
|
|
|
|
io = sh->log_io;
|
|
sh->log_io = NULL;
|
|
|
|
if (io && atomic_dec_and_test(&io->pending_stripe))
|
|
__r5l_stripe_write_finished(io);
|
|
}
|
|
|
|
static void r5l_log_flush_endio(struct bio *bio)
|
|
{
|
|
struct r5l_log *log = container_of(bio, struct r5l_log,
|
|
flush_bio);
|
|
unsigned long flags;
|
|
struct r5l_io_unit *io;
|
|
|
|
if (bio->bi_error)
|
|
md_error(log->rdev->mddev, log->rdev);
|
|
|
|
spin_lock_irqsave(&log->io_list_lock, flags);
|
|
list_for_each_entry(io, &log->flushing_ios, log_sibling)
|
|
r5l_io_run_stripes(io);
|
|
list_splice_tail_init(&log->flushing_ios, &log->finished_ios);
|
|
spin_unlock_irqrestore(&log->io_list_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* Starting dispatch IO to raid.
|
|
* io_unit(meta) consists of a log. There is one situation we want to avoid. A
|
|
* broken meta in the middle of a log causes recovery can't find meta at the
|
|
* head of log. If operations require meta at the head persistent in log, we
|
|
* must make sure meta before it persistent in log too. A case is:
|
|
*
|
|
* stripe data/parity is in log, we start write stripe to raid disks. stripe
|
|
* data/parity must be persistent in log before we do the write to raid disks.
|
|
*
|
|
* The solution is we restrictly maintain io_unit list order. In this case, we
|
|
* only write stripes of an io_unit to raid disks till the io_unit is the first
|
|
* one whose data/parity is in log.
|
|
*/
|
|
void r5l_flush_stripe_to_raid(struct r5l_log *log)
|
|
{
|
|
bool do_flush;
|
|
|
|
if (!log || !log->need_cache_flush)
|
|
return;
|
|
|
|
spin_lock_irq(&log->io_list_lock);
|
|
/* flush bio is running */
|
|
if (!list_empty(&log->flushing_ios)) {
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
return;
|
|
}
|
|
list_splice_tail_init(&log->io_end_ios, &log->flushing_ios);
|
|
do_flush = !list_empty(&log->flushing_ios);
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
|
|
if (!do_flush)
|
|
return;
|
|
bio_reset(&log->flush_bio);
|
|
log->flush_bio.bi_bdev = log->rdev->bdev;
|
|
log->flush_bio.bi_end_io = r5l_log_flush_endio;
|
|
log->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
|
|
submit_bio(&log->flush_bio);
|
|
}
|
|
|
|
static void r5l_write_super(struct r5l_log *log, sector_t cp);
|
|
static void r5l_write_super_and_discard_space(struct r5l_log *log,
|
|
sector_t end)
|
|
{
|
|
struct block_device *bdev = log->rdev->bdev;
|
|
struct mddev *mddev;
|
|
|
|
r5l_write_super(log, end);
|
|
|
|
if (!blk_queue_discard(bdev_get_queue(bdev)))
|
|
return;
|
|
|
|
mddev = log->rdev->mddev;
|
|
/*
|
|
* Discard could zero data, so before discard we must make sure
|
|
* superblock is updated to new log tail. Updating superblock (either
|
|
* directly call md_update_sb() or depend on md thread) must hold
|
|
* reconfig mutex. On the other hand, raid5_quiesce is called with
|
|
* reconfig_mutex hold. The first step of raid5_quiesce() is waitting
|
|
* for all IO finish, hence waitting for reclaim thread, while reclaim
|
|
* thread is calling this function and waitting for reconfig mutex. So
|
|
* there is a deadlock. We workaround this issue with a trylock.
|
|
* FIXME: we could miss discard if we can't take reconfig mutex
|
|
*/
|
|
set_mask_bits(&mddev->sb_flags, 0,
|
|
BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
|
|
if (!mddev_trylock(mddev))
|
|
return;
|
|
md_update_sb(mddev, 1);
|
|
mddev_unlock(mddev);
|
|
|
|
/* discard IO error really doesn't matter, ignore it */
|
|
if (log->last_checkpoint < end) {
|
|
blkdev_issue_discard(bdev,
|
|
log->last_checkpoint + log->rdev->data_offset,
|
|
end - log->last_checkpoint, GFP_NOIO, 0);
|
|
} else {
|
|
blkdev_issue_discard(bdev,
|
|
log->last_checkpoint + log->rdev->data_offset,
|
|
log->device_size - log->last_checkpoint,
|
|
GFP_NOIO, 0);
|
|
blkdev_issue_discard(bdev, log->rdev->data_offset, end,
|
|
GFP_NOIO, 0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* r5c_flush_stripe moves stripe from cached list to handle_list. When called,
|
|
* the stripe must be on r5c_cached_full_stripes or r5c_cached_partial_stripes.
|
|
*
|
|
* must hold conf->device_lock
|
|
*/
|
|
static void r5c_flush_stripe(struct r5conf *conf, struct stripe_head *sh)
|
|
{
|
|
BUG_ON(list_empty(&sh->lru));
|
|
BUG_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state));
|
|
BUG_ON(test_bit(STRIPE_HANDLE, &sh->state));
|
|
|
|
/*
|
|
* The stripe is not ON_RELEASE_LIST, so it is safe to call
|
|
* raid5_release_stripe() while holding conf->device_lock
|
|
*/
|
|
BUG_ON(test_bit(STRIPE_ON_RELEASE_LIST, &sh->state));
|
|
assert_spin_locked(&conf->device_lock);
|
|
|
|
list_del_init(&sh->lru);
|
|
atomic_inc(&sh->count);
|
|
|
|
set_bit(STRIPE_HANDLE, &sh->state);
|
|
atomic_inc(&conf->active_stripes);
|
|
r5c_make_stripe_write_out(sh);
|
|
|
|
raid5_release_stripe(sh);
|
|
}
|
|
|
|
/*
|
|
* if num == 0, flush all full stripes
|
|
* if num > 0, flush all full stripes. If less than num full stripes are
|
|
* flushed, flush some partial stripes until totally num stripes are
|
|
* flushed or there is no more cached stripes.
|
|
*/
|
|
void r5c_flush_cache(struct r5conf *conf, int num)
|
|
{
|
|
int count;
|
|
struct stripe_head *sh, *next;
|
|
|
|
assert_spin_locked(&conf->device_lock);
|
|
if (!conf->log)
|
|
return;
|
|
|
|
count = 0;
|
|
list_for_each_entry_safe(sh, next, &conf->r5c_full_stripe_list, lru) {
|
|
r5c_flush_stripe(conf, sh);
|
|
count++;
|
|
}
|
|
|
|
if (count >= num)
|
|
return;
|
|
list_for_each_entry_safe(sh, next,
|
|
&conf->r5c_partial_stripe_list, lru) {
|
|
r5c_flush_stripe(conf, sh);
|
|
if (++count >= num)
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void r5c_do_reclaim(struct r5conf *conf)
|
|
{
|
|
struct r5l_log *log = conf->log;
|
|
struct stripe_head *sh;
|
|
int count = 0;
|
|
unsigned long flags;
|
|
int total_cached;
|
|
int stripes_to_flush;
|
|
|
|
if (!r5c_is_writeback(log))
|
|
return;
|
|
|
|
total_cached = atomic_read(&conf->r5c_cached_partial_stripes) +
|
|
atomic_read(&conf->r5c_cached_full_stripes);
|
|
|
|
if (total_cached > conf->min_nr_stripes * 3 / 4 ||
|
|
atomic_read(&conf->empty_inactive_list_nr) > 0)
|
|
/*
|
|
* if stripe cache pressure high, flush all full stripes and
|
|
* some partial stripes
|
|
*/
|
|
stripes_to_flush = R5C_RECLAIM_STRIPE_GROUP;
|
|
else if (total_cached > conf->min_nr_stripes * 1 / 2 ||
|
|
atomic_read(&conf->r5c_cached_full_stripes) >
|
|
R5C_FULL_STRIPE_FLUSH_BATCH)
|
|
/*
|
|
* if stripe cache pressure moderate, or if there is many full
|
|
* stripes,flush all full stripes
|
|
*/
|
|
stripes_to_flush = 0;
|
|
else
|
|
/* no need to flush */
|
|
stripes_to_flush = -1;
|
|
|
|
if (stripes_to_flush >= 0) {
|
|
spin_lock_irqsave(&conf->device_lock, flags);
|
|
r5c_flush_cache(conf, stripes_to_flush);
|
|
spin_unlock_irqrestore(&conf->device_lock, flags);
|
|
}
|
|
|
|
/* if log space is tight, flush stripes on stripe_in_journal_list */
|
|
if (test_bit(R5C_LOG_TIGHT, &conf->cache_state)) {
|
|
spin_lock_irqsave(&log->stripe_in_journal_lock, flags);
|
|
spin_lock(&conf->device_lock);
|
|
list_for_each_entry(sh, &log->stripe_in_journal_list, r5c) {
|
|
/*
|
|
* stripes on stripe_in_journal_list could be in any
|
|
* state of the stripe_cache state machine. In this
|
|
* case, we only want to flush stripe on
|
|
* r5c_cached_full/partial_stripes. The following
|
|
* condition makes sure the stripe is on one of the
|
|
* two lists.
|
|
*/
|
|
if (!list_empty(&sh->lru) &&
|
|
!test_bit(STRIPE_HANDLE, &sh->state) &&
|
|
atomic_read(&sh->count) == 0) {
|
|
r5c_flush_stripe(conf, sh);
|
|
}
|
|
if (count++ >= R5C_RECLAIM_STRIPE_GROUP)
|
|
break;
|
|
}
|
|
spin_unlock(&conf->device_lock);
|
|
spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags);
|
|
}
|
|
|
|
if (!test_bit(R5C_LOG_CRITICAL, &conf->cache_state))
|
|
r5l_run_no_space_stripes(log);
|
|
|
|
md_wakeup_thread(conf->mddev->thread);
|
|
}
|
|
|
|
static void r5l_do_reclaim(struct r5l_log *log)
|
|
{
|
|
struct r5conf *conf = log->rdev->mddev->private;
|
|
sector_t reclaim_target = xchg(&log->reclaim_target, 0);
|
|
sector_t reclaimable;
|
|
sector_t next_checkpoint;
|
|
bool write_super;
|
|
|
|
spin_lock_irq(&log->io_list_lock);
|
|
write_super = r5l_reclaimable_space(log) > log->max_free_space ||
|
|
reclaim_target != 0 || !list_empty(&log->no_space_stripes);
|
|
/*
|
|
* move proper io_unit to reclaim list. We should not change the order.
|
|
* reclaimable/unreclaimable io_unit can be mixed in the list, we
|
|
* shouldn't reuse space of an unreclaimable io_unit
|
|
*/
|
|
while (1) {
|
|
reclaimable = r5l_reclaimable_space(log);
|
|
if (reclaimable >= reclaim_target ||
|
|
(list_empty(&log->running_ios) &&
|
|
list_empty(&log->io_end_ios) &&
|
|
list_empty(&log->flushing_ios) &&
|
|
list_empty(&log->finished_ios)))
|
|
break;
|
|
|
|
md_wakeup_thread(log->rdev->mddev->thread);
|
|
wait_event_lock_irq(log->iounit_wait,
|
|
r5l_reclaimable_space(log) > reclaimable,
|
|
log->io_list_lock);
|
|
}
|
|
|
|
next_checkpoint = r5c_calculate_new_cp(conf);
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
|
|
if (reclaimable == 0 || !write_super)
|
|
return;
|
|
|
|
/*
|
|
* write_super will flush cache of each raid disk. We must write super
|
|
* here, because the log area might be reused soon and we don't want to
|
|
* confuse recovery
|
|
*/
|
|
r5l_write_super_and_discard_space(log, next_checkpoint);
|
|
|
|
mutex_lock(&log->io_mutex);
|
|
log->last_checkpoint = next_checkpoint;
|
|
r5c_update_log_state(log);
|
|
mutex_unlock(&log->io_mutex);
|
|
|
|
r5l_run_no_space_stripes(log);
|
|
}
|
|
|
|
static void r5l_reclaim_thread(struct md_thread *thread)
|
|
{
|
|
struct mddev *mddev = thread->mddev;
|
|
struct r5conf *conf = mddev->private;
|
|
struct r5l_log *log = conf->log;
|
|
|
|
if (!log)
|
|
return;
|
|
r5c_do_reclaim(conf);
|
|
r5l_do_reclaim(log);
|
|
}
|
|
|
|
void r5l_wake_reclaim(struct r5l_log *log, sector_t space)
|
|
{
|
|
unsigned long target;
|
|
unsigned long new = (unsigned long)space; /* overflow in theory */
|
|
|
|
if (!log)
|
|
return;
|
|
do {
|
|
target = log->reclaim_target;
|
|
if (new < target)
|
|
return;
|
|
} while (cmpxchg(&log->reclaim_target, target, new) != target);
|
|
md_wakeup_thread(log->reclaim_thread);
|
|
}
|
|
|
|
void r5l_quiesce(struct r5l_log *log, int state)
|
|
{
|
|
struct mddev *mddev;
|
|
if (!log || state == 2)
|
|
return;
|
|
if (state == 0)
|
|
kthread_unpark(log->reclaim_thread->tsk);
|
|
else if (state == 1) {
|
|
/* make sure r5l_write_super_and_discard_space exits */
|
|
mddev = log->rdev->mddev;
|
|
wake_up(&mddev->sb_wait);
|
|
kthread_park(log->reclaim_thread->tsk);
|
|
r5l_wake_reclaim(log, MaxSector);
|
|
r5l_do_reclaim(log);
|
|
}
|
|
}
|
|
|
|
bool r5l_log_disk_error(struct r5conf *conf)
|
|
{
|
|
struct r5l_log *log;
|
|
bool ret;
|
|
/* don't allow write if journal disk is missing */
|
|
rcu_read_lock();
|
|
log = rcu_dereference(conf->log);
|
|
|
|
if (!log)
|
|
ret = test_bit(MD_HAS_JOURNAL, &conf->mddev->flags);
|
|
else
|
|
ret = test_bit(Faulty, &log->rdev->flags);
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
struct r5l_recovery_ctx {
|
|
struct page *meta_page; /* current meta */
|
|
sector_t meta_total_blocks; /* total size of current meta and data */
|
|
sector_t pos; /* recovery position */
|
|
u64 seq; /* recovery position seq */
|
|
int data_parity_stripes; /* number of data_parity stripes */
|
|
int data_only_stripes; /* number of data_only stripes */
|
|
struct list_head cached_list;
|
|
};
|
|
|
|
static int r5l_recovery_read_meta_block(struct r5l_log *log,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct page *page = ctx->meta_page;
|
|
struct r5l_meta_block *mb;
|
|
u32 crc, stored_crc;
|
|
|
|
if (!sync_page_io(log->rdev, ctx->pos, PAGE_SIZE, page, REQ_OP_READ, 0,
|
|
false))
|
|
return -EIO;
|
|
|
|
mb = page_address(page);
|
|
stored_crc = le32_to_cpu(mb->checksum);
|
|
mb->checksum = 0;
|
|
|
|
if (le32_to_cpu(mb->magic) != R5LOG_MAGIC ||
|
|
le64_to_cpu(mb->seq) != ctx->seq ||
|
|
mb->version != R5LOG_VERSION ||
|
|
le64_to_cpu(mb->position) != ctx->pos)
|
|
return -EINVAL;
|
|
|
|
crc = crc32c_le(log->uuid_checksum, mb, PAGE_SIZE);
|
|
if (stored_crc != crc)
|
|
return -EINVAL;
|
|
|
|
if (le32_to_cpu(mb->meta_size) > PAGE_SIZE)
|
|
return -EINVAL;
|
|
|
|
ctx->meta_total_blocks = BLOCK_SECTORS;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
r5l_recovery_create_empty_meta_block(struct r5l_log *log,
|
|
struct page *page,
|
|
sector_t pos, u64 seq)
|
|
{
|
|
struct r5l_meta_block *mb;
|
|
|
|
mb = page_address(page);
|
|
clear_page(mb);
|
|
mb->magic = cpu_to_le32(R5LOG_MAGIC);
|
|
mb->version = R5LOG_VERSION;
|
|
mb->meta_size = cpu_to_le32(sizeof(struct r5l_meta_block));
|
|
mb->seq = cpu_to_le64(seq);
|
|
mb->position = cpu_to_le64(pos);
|
|
}
|
|
|
|
static int r5l_log_write_empty_meta_block(struct r5l_log *log, sector_t pos,
|
|
u64 seq)
|
|
{
|
|
struct page *page;
|
|
struct r5l_meta_block *mb;
|
|
|
|
page = alloc_page(GFP_KERNEL);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
r5l_recovery_create_empty_meta_block(log, page, pos, seq);
|
|
mb = page_address(page);
|
|
mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum,
|
|
mb, PAGE_SIZE));
|
|
if (!sync_page_io(log->rdev, pos, PAGE_SIZE, page, REQ_OP_WRITE,
|
|
REQ_FUA, false)) {
|
|
__free_page(page);
|
|
return -EIO;
|
|
}
|
|
__free_page(page);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* r5l_recovery_load_data and r5l_recovery_load_parity uses flag R5_Wantwrite
|
|
* to mark valid (potentially not flushed) data in the journal.
|
|
*
|
|
* We already verified checksum in r5l_recovery_verify_data_checksum_for_mb,
|
|
* so there should not be any mismatch here.
|
|
*/
|
|
static void r5l_recovery_load_data(struct r5l_log *log,
|
|
struct stripe_head *sh,
|
|
struct r5l_recovery_ctx *ctx,
|
|
struct r5l_payload_data_parity *payload,
|
|
sector_t log_offset)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct r5conf *conf = mddev->private;
|
|
int dd_idx;
|
|
|
|
raid5_compute_sector(conf,
|
|
le64_to_cpu(payload->location), 0,
|
|
&dd_idx, sh);
|
|
sync_page_io(log->rdev, log_offset, PAGE_SIZE,
|
|
sh->dev[dd_idx].page, REQ_OP_READ, 0, false);
|
|
sh->dev[dd_idx].log_checksum =
|
|
le32_to_cpu(payload->checksum[0]);
|
|
ctx->meta_total_blocks += BLOCK_SECTORS;
|
|
|
|
set_bit(R5_Wantwrite, &sh->dev[dd_idx].flags);
|
|
set_bit(STRIPE_R5C_CACHING, &sh->state);
|
|
}
|
|
|
|
static void r5l_recovery_load_parity(struct r5l_log *log,
|
|
struct stripe_head *sh,
|
|
struct r5l_recovery_ctx *ctx,
|
|
struct r5l_payload_data_parity *payload,
|
|
sector_t log_offset)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct r5conf *conf = mddev->private;
|
|
|
|
ctx->meta_total_blocks += BLOCK_SECTORS * conf->max_degraded;
|
|
sync_page_io(log->rdev, log_offset, PAGE_SIZE,
|
|
sh->dev[sh->pd_idx].page, REQ_OP_READ, 0, false);
|
|
sh->dev[sh->pd_idx].log_checksum =
|
|
le32_to_cpu(payload->checksum[0]);
|
|
set_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags);
|
|
|
|
if (sh->qd_idx >= 0) {
|
|
sync_page_io(log->rdev,
|
|
r5l_ring_add(log, log_offset, BLOCK_SECTORS),
|
|
PAGE_SIZE, sh->dev[sh->qd_idx].page,
|
|
REQ_OP_READ, 0, false);
|
|
sh->dev[sh->qd_idx].log_checksum =
|
|
le32_to_cpu(payload->checksum[1]);
|
|
set_bit(R5_Wantwrite, &sh->dev[sh->qd_idx].flags);
|
|
}
|
|
clear_bit(STRIPE_R5C_CACHING, &sh->state);
|
|
}
|
|
|
|
static void r5l_recovery_reset_stripe(struct stripe_head *sh)
|
|
{
|
|
int i;
|
|
|
|
sh->state = 0;
|
|
sh->log_start = MaxSector;
|
|
for (i = sh->disks; i--; )
|
|
sh->dev[i].flags = 0;
|
|
}
|
|
|
|
static void
|
|
r5l_recovery_replay_one_stripe(struct r5conf *conf,
|
|
struct stripe_head *sh,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct md_rdev *rdev, *rrdev;
|
|
int disk_index;
|
|
int data_count = 0;
|
|
|
|
for (disk_index = 0; disk_index < sh->disks; disk_index++) {
|
|
if (!test_bit(R5_Wantwrite, &sh->dev[disk_index].flags))
|
|
continue;
|
|
if (disk_index == sh->qd_idx || disk_index == sh->pd_idx)
|
|
continue;
|
|
data_count++;
|
|
}
|
|
|
|
/*
|
|
* stripes that only have parity must have been flushed
|
|
* before the crash that we are now recovering from, so
|
|
* there is nothing more to recovery.
|
|
*/
|
|
if (data_count == 0)
|
|
goto out;
|
|
|
|
for (disk_index = 0; disk_index < sh->disks; disk_index++) {
|
|
if (!test_bit(R5_Wantwrite, &sh->dev[disk_index].flags))
|
|
continue;
|
|
|
|
/* in case device is broken */
|
|
rcu_read_lock();
|
|
rdev = rcu_dereference(conf->disks[disk_index].rdev);
|
|
if (rdev) {
|
|
atomic_inc(&rdev->nr_pending);
|
|
rcu_read_unlock();
|
|
sync_page_io(rdev, sh->sector, PAGE_SIZE,
|
|
sh->dev[disk_index].page, REQ_OP_WRITE, 0,
|
|
false);
|
|
rdev_dec_pending(rdev, rdev->mddev);
|
|
rcu_read_lock();
|
|
}
|
|
rrdev = rcu_dereference(conf->disks[disk_index].replacement);
|
|
if (rrdev) {
|
|
atomic_inc(&rrdev->nr_pending);
|
|
rcu_read_unlock();
|
|
sync_page_io(rrdev, sh->sector, PAGE_SIZE,
|
|
sh->dev[disk_index].page, REQ_OP_WRITE, 0,
|
|
false);
|
|
rdev_dec_pending(rrdev, rrdev->mddev);
|
|
rcu_read_lock();
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
ctx->data_parity_stripes++;
|
|
out:
|
|
r5l_recovery_reset_stripe(sh);
|
|
}
|
|
|
|
static struct stripe_head *
|
|
r5c_recovery_alloc_stripe(struct r5conf *conf,
|
|
sector_t stripe_sect)
|
|
{
|
|
struct stripe_head *sh;
|
|
|
|
sh = raid5_get_active_stripe(conf, stripe_sect, 0, 1, 0);
|
|
if (!sh)
|
|
return NULL; /* no more stripe available */
|
|
|
|
r5l_recovery_reset_stripe(sh);
|
|
|
|
return sh;
|
|
}
|
|
|
|
static struct stripe_head *
|
|
r5c_recovery_lookup_stripe(struct list_head *list, sector_t sect)
|
|
{
|
|
struct stripe_head *sh;
|
|
|
|
list_for_each_entry(sh, list, lru)
|
|
if (sh->sector == sect)
|
|
return sh;
|
|
return NULL;
|
|
}
|
|
|
|
static void
|
|
r5c_recovery_drop_stripes(struct list_head *cached_stripe_list,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct stripe_head *sh, *next;
|
|
|
|
list_for_each_entry_safe(sh, next, cached_stripe_list, lru) {
|
|
r5l_recovery_reset_stripe(sh);
|
|
list_del_init(&sh->lru);
|
|
raid5_release_stripe(sh);
|
|
}
|
|
}
|
|
|
|
static void
|
|
r5c_recovery_replay_stripes(struct list_head *cached_stripe_list,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct stripe_head *sh, *next;
|
|
|
|
list_for_each_entry_safe(sh, next, cached_stripe_list, lru)
|
|
if (!test_bit(STRIPE_R5C_CACHING, &sh->state)) {
|
|
r5l_recovery_replay_one_stripe(sh->raid_conf, sh, ctx);
|
|
list_del_init(&sh->lru);
|
|
raid5_release_stripe(sh);
|
|
}
|
|
}
|
|
|
|
/* if matches return 0; otherwise return -EINVAL */
|
|
static int
|
|
r5l_recovery_verify_data_checksum(struct r5l_log *log, struct page *page,
|
|
sector_t log_offset, __le32 log_checksum)
|
|
{
|
|
void *addr;
|
|
u32 checksum;
|
|
|
|
sync_page_io(log->rdev, log_offset, PAGE_SIZE,
|
|
page, REQ_OP_READ, 0, false);
|
|
addr = kmap_atomic(page);
|
|
checksum = crc32c_le(log->uuid_checksum, addr, PAGE_SIZE);
|
|
kunmap_atomic(addr);
|
|
return (le32_to_cpu(log_checksum) == checksum) ? 0 : -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* before loading data to stripe cache, we need verify checksum for all data,
|
|
* if there is mismatch for any data page, we drop all data in the mata block
|
|
*/
|
|
static int
|
|
r5l_recovery_verify_data_checksum_for_mb(struct r5l_log *log,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct r5conf *conf = mddev->private;
|
|
struct r5l_meta_block *mb = page_address(ctx->meta_page);
|
|
sector_t mb_offset = sizeof(struct r5l_meta_block);
|
|
sector_t log_offset = r5l_ring_add(log, ctx->pos, BLOCK_SECTORS);
|
|
struct page *page;
|
|
struct r5l_payload_data_parity *payload;
|
|
|
|
page = alloc_page(GFP_KERNEL);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
while (mb_offset < le32_to_cpu(mb->meta_size)) {
|
|
payload = (void *)mb + mb_offset;
|
|
|
|
if (payload->header.type == R5LOG_PAYLOAD_DATA) {
|
|
if (r5l_recovery_verify_data_checksum(
|
|
log, page, log_offset,
|
|
payload->checksum[0]) < 0)
|
|
goto mismatch;
|
|
} else if (payload->header.type == R5LOG_PAYLOAD_PARITY) {
|
|
if (r5l_recovery_verify_data_checksum(
|
|
log, page, log_offset,
|
|
payload->checksum[0]) < 0)
|
|
goto mismatch;
|
|
if (conf->max_degraded == 2 && /* q for RAID 6 */
|
|
r5l_recovery_verify_data_checksum(
|
|
log, page,
|
|
r5l_ring_add(log, log_offset,
|
|
BLOCK_SECTORS),
|
|
payload->checksum[1]) < 0)
|
|
goto mismatch;
|
|
} else /* not R5LOG_PAYLOAD_DATA or R5LOG_PAYLOAD_PARITY */
|
|
goto mismatch;
|
|
|
|
log_offset = r5l_ring_add(log, log_offset,
|
|
le32_to_cpu(payload->size));
|
|
|
|
mb_offset += sizeof(struct r5l_payload_data_parity) +
|
|
sizeof(__le32) *
|
|
(le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9));
|
|
}
|
|
|
|
put_page(page);
|
|
return 0;
|
|
|
|
mismatch:
|
|
put_page(page);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Analyze all data/parity pages in one meta block
|
|
* Returns:
|
|
* 0 for success
|
|
* -EINVAL for unknown playload type
|
|
* -EAGAIN for checksum mismatch of data page
|
|
* -ENOMEM for run out of memory (alloc_page failed or run out of stripes)
|
|
*/
|
|
static int
|
|
r5c_recovery_analyze_meta_block(struct r5l_log *log,
|
|
struct r5l_recovery_ctx *ctx,
|
|
struct list_head *cached_stripe_list)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct r5conf *conf = mddev->private;
|
|
struct r5l_meta_block *mb;
|
|
struct r5l_payload_data_parity *payload;
|
|
int mb_offset;
|
|
sector_t log_offset;
|
|
sector_t stripe_sect;
|
|
struct stripe_head *sh;
|
|
int ret;
|
|
|
|
/*
|
|
* for mismatch in data blocks, we will drop all data in this mb, but
|
|
* we will still read next mb for other data with FLUSH flag, as
|
|
* io_unit could finish out of order.
|
|
*/
|
|
ret = r5l_recovery_verify_data_checksum_for_mb(log, ctx);
|
|
if (ret == -EINVAL)
|
|
return -EAGAIN;
|
|
else if (ret)
|
|
return ret; /* -ENOMEM duo to alloc_page() failed */
|
|
|
|
mb = page_address(ctx->meta_page);
|
|
mb_offset = sizeof(struct r5l_meta_block);
|
|
log_offset = r5l_ring_add(log, ctx->pos, BLOCK_SECTORS);
|
|
|
|
while (mb_offset < le32_to_cpu(mb->meta_size)) {
|
|
int dd;
|
|
|
|
payload = (void *)mb + mb_offset;
|
|
stripe_sect = (payload->header.type == R5LOG_PAYLOAD_DATA) ?
|
|
raid5_compute_sector(
|
|
conf, le64_to_cpu(payload->location), 0, &dd,
|
|
NULL)
|
|
: le64_to_cpu(payload->location);
|
|
|
|
sh = r5c_recovery_lookup_stripe(cached_stripe_list,
|
|
stripe_sect);
|
|
|
|
if (!sh) {
|
|
sh = r5c_recovery_alloc_stripe(conf, stripe_sect);
|
|
/*
|
|
* cannot get stripe from raid5_get_active_stripe
|
|
* try replay some stripes
|
|
*/
|
|
if (!sh) {
|
|
r5c_recovery_replay_stripes(
|
|
cached_stripe_list, ctx);
|
|
sh = r5c_recovery_alloc_stripe(
|
|
conf, stripe_sect);
|
|
}
|
|
if (!sh) {
|
|
pr_debug("md/raid:%s: Increasing stripe cache size to %d to recovery data on journal.\n",
|
|
mdname(mddev),
|
|
conf->min_nr_stripes * 2);
|
|
raid5_set_cache_size(mddev,
|
|
conf->min_nr_stripes * 2);
|
|
sh = r5c_recovery_alloc_stripe(conf,
|
|
stripe_sect);
|
|
}
|
|
if (!sh) {
|
|
pr_err("md/raid:%s: Cannot get enough stripes due to memory pressure. Recovery failed.\n",
|
|
mdname(mddev));
|
|
return -ENOMEM;
|
|
}
|
|
list_add_tail(&sh->lru, cached_stripe_list);
|
|
}
|
|
|
|
if (payload->header.type == R5LOG_PAYLOAD_DATA) {
|
|
if (!test_bit(STRIPE_R5C_CACHING, &sh->state) &&
|
|
test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags)) {
|
|
r5l_recovery_replay_one_stripe(conf, sh, ctx);
|
|
list_move_tail(&sh->lru, cached_stripe_list);
|
|
}
|
|
r5l_recovery_load_data(log, sh, ctx, payload,
|
|
log_offset);
|
|
} else if (payload->header.type == R5LOG_PAYLOAD_PARITY)
|
|
r5l_recovery_load_parity(log, sh, ctx, payload,
|
|
log_offset);
|
|
else
|
|
return -EINVAL;
|
|
|
|
log_offset = r5l_ring_add(log, log_offset,
|
|
le32_to_cpu(payload->size));
|
|
|
|
mb_offset += sizeof(struct r5l_payload_data_parity) +
|
|
sizeof(__le32) *
|
|
(le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9));
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Load the stripe into cache. The stripe will be written out later by
|
|
* the stripe cache state machine.
|
|
*/
|
|
static void r5c_recovery_load_one_stripe(struct r5l_log *log,
|
|
struct stripe_head *sh)
|
|
{
|
|
struct r5dev *dev;
|
|
int i;
|
|
|
|
for (i = sh->disks; i--; ) {
|
|
dev = sh->dev + i;
|
|
if (test_and_clear_bit(R5_Wantwrite, &dev->flags)) {
|
|
set_bit(R5_InJournal, &dev->flags);
|
|
set_bit(R5_UPTODATE, &dev->flags);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Scan through the log for all to-be-flushed data
|
|
*
|
|
* For stripes with data and parity, namely Data-Parity stripe
|
|
* (STRIPE_R5C_CACHING == 0), we simply replay all the writes.
|
|
*
|
|
* For stripes with only data, namely Data-Only stripe
|
|
* (STRIPE_R5C_CACHING == 1), we load them to stripe cache state machine.
|
|
*
|
|
* For a stripe, if we see data after parity, we should discard all previous
|
|
* data and parity for this stripe, as these data are already flushed to
|
|
* the array.
|
|
*
|
|
* At the end of the scan, we return the new journal_tail, which points to
|
|
* first data-only stripe on the journal device, or next invalid meta block.
|
|
*/
|
|
static int r5c_recovery_flush_log(struct r5l_log *log,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct stripe_head *sh;
|
|
int ret = 0;
|
|
|
|
/* scan through the log */
|
|
while (1) {
|
|
if (r5l_recovery_read_meta_block(log, ctx))
|
|
break;
|
|
|
|
ret = r5c_recovery_analyze_meta_block(log, ctx,
|
|
&ctx->cached_list);
|
|
/*
|
|
* -EAGAIN means mismatch in data block, in this case, we still
|
|
* try scan the next metablock
|
|
*/
|
|
if (ret && ret != -EAGAIN)
|
|
break; /* ret == -EINVAL or -ENOMEM */
|
|
ctx->seq++;
|
|
ctx->pos = r5l_ring_add(log, ctx->pos, ctx->meta_total_blocks);
|
|
}
|
|
|
|
if (ret == -ENOMEM) {
|
|
r5c_recovery_drop_stripes(&ctx->cached_list, ctx);
|
|
return ret;
|
|
}
|
|
|
|
/* replay data-parity stripes */
|
|
r5c_recovery_replay_stripes(&ctx->cached_list, ctx);
|
|
|
|
/* load data-only stripes to stripe cache */
|
|
list_for_each_entry(sh, &ctx->cached_list, lru) {
|
|
WARN_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state));
|
|
r5c_recovery_load_one_stripe(log, sh);
|
|
ctx->data_only_stripes++;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* we did a recovery. Now ctx.pos points to an invalid meta block. New
|
|
* log will start here. but we can't let superblock point to last valid
|
|
* meta block. The log might looks like:
|
|
* | meta 1| meta 2| meta 3|
|
|
* meta 1 is valid, meta 2 is invalid. meta 3 could be valid. If
|
|
* superblock points to meta 1, we write a new valid meta 2n. if crash
|
|
* happens again, new recovery will start from meta 1. Since meta 2n is
|
|
* valid now, recovery will think meta 3 is valid, which is wrong.
|
|
* The solution is we create a new meta in meta2 with its seq == meta
|
|
* 1's seq + 10000 and let superblock points to meta2. The same recovery
|
|
* will not think meta 3 is a valid meta, because its seq doesn't match
|
|
*/
|
|
|
|
/*
|
|
* Before recovery, the log looks like the following
|
|
*
|
|
* ---------------------------------------------
|
|
* | valid log | invalid log |
|
|
* ---------------------------------------------
|
|
* ^
|
|
* |- log->last_checkpoint
|
|
* |- log->last_cp_seq
|
|
*
|
|
* Now we scan through the log until we see invalid entry
|
|
*
|
|
* ---------------------------------------------
|
|
* | valid log | invalid log |
|
|
* ---------------------------------------------
|
|
* ^ ^
|
|
* |- log->last_checkpoint |- ctx->pos
|
|
* |- log->last_cp_seq |- ctx->seq
|
|
*
|
|
* From this point, we need to increase seq number by 10 to avoid
|
|
* confusing next recovery.
|
|
*
|
|
* ---------------------------------------------
|
|
* | valid log | invalid log |
|
|
* ---------------------------------------------
|
|
* ^ ^
|
|
* |- log->last_checkpoint |- ctx->pos+1
|
|
* |- log->last_cp_seq |- ctx->seq+10001
|
|
*
|
|
* However, it is not safe to start the state machine yet, because data only
|
|
* parities are not yet secured in RAID. To save these data only parities, we
|
|
* rewrite them from seq+11.
|
|
*
|
|
* -----------------------------------------------------------------
|
|
* | valid log | data only stripes | invalid log |
|
|
* -----------------------------------------------------------------
|
|
* ^ ^
|
|
* |- log->last_checkpoint |- ctx->pos+n
|
|
* |- log->last_cp_seq |- ctx->seq+10000+n
|
|
*
|
|
* If failure happens again during this process, the recovery can safe start
|
|
* again from log->last_checkpoint.
|
|
*
|
|
* Once data only stripes are rewritten to journal, we move log_tail
|
|
*
|
|
* -----------------------------------------------------------------
|
|
* | old log | data only stripes | invalid log |
|
|
* -----------------------------------------------------------------
|
|
* ^ ^
|
|
* |- log->last_checkpoint |- ctx->pos+n
|
|
* |- log->last_cp_seq |- ctx->seq+10000+n
|
|
*
|
|
* Then we can safely start the state machine. If failure happens from this
|
|
* point on, the recovery will start from new log->last_checkpoint.
|
|
*/
|
|
static int
|
|
r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct stripe_head *sh;
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct page *page;
|
|
sector_t next_checkpoint = MaxSector;
|
|
|
|
page = alloc_page(GFP_KERNEL);
|
|
if (!page) {
|
|
pr_err("md/raid:%s: cannot allocate memory to rewrite data only stripes\n",
|
|
mdname(mddev));
|
|
return -ENOMEM;
|
|
}
|
|
|
|
WARN_ON(list_empty(&ctx->cached_list));
|
|
|
|
list_for_each_entry(sh, &ctx->cached_list, lru) {
|
|
struct r5l_meta_block *mb;
|
|
int i;
|
|
int offset;
|
|
sector_t write_pos;
|
|
|
|
WARN_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state));
|
|
r5l_recovery_create_empty_meta_block(log, page,
|
|
ctx->pos, ctx->seq);
|
|
mb = page_address(page);
|
|
offset = le32_to_cpu(mb->meta_size);
|
|
write_pos = r5l_ring_add(log, ctx->pos, BLOCK_SECTORS);
|
|
|
|
for (i = sh->disks; i--; ) {
|
|
struct r5dev *dev = &sh->dev[i];
|
|
struct r5l_payload_data_parity *payload;
|
|
void *addr;
|
|
|
|
if (test_bit(R5_InJournal, &dev->flags)) {
|
|
payload = (void *)mb + offset;
|
|
payload->header.type = cpu_to_le16(
|
|
R5LOG_PAYLOAD_DATA);
|
|
payload->size = BLOCK_SECTORS;
|
|
payload->location = cpu_to_le64(
|
|
raid5_compute_blocknr(sh, i, 0));
|
|
addr = kmap_atomic(dev->page);
|
|
payload->checksum[0] = cpu_to_le32(
|
|
crc32c_le(log->uuid_checksum, addr,
|
|
PAGE_SIZE));
|
|
kunmap_atomic(addr);
|
|
sync_page_io(log->rdev, write_pos, PAGE_SIZE,
|
|
dev->page, REQ_OP_WRITE, 0, false);
|
|
write_pos = r5l_ring_add(log, write_pos,
|
|
BLOCK_SECTORS);
|
|
offset += sizeof(__le32) +
|
|
sizeof(struct r5l_payload_data_parity);
|
|
|
|
}
|
|
}
|
|
mb->meta_size = cpu_to_le32(offset);
|
|
mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum,
|
|
mb, PAGE_SIZE));
|
|
sync_page_io(log->rdev, ctx->pos, PAGE_SIZE, page,
|
|
REQ_OP_WRITE, REQ_FUA, false);
|
|
sh->log_start = ctx->pos;
|
|
list_add_tail(&sh->r5c, &log->stripe_in_journal_list);
|
|
atomic_inc(&log->stripe_in_journal_count);
|
|
ctx->pos = write_pos;
|
|
ctx->seq += 1;
|
|
next_checkpoint = sh->log_start;
|
|
}
|
|
log->next_checkpoint = next_checkpoint;
|
|
__free_page(page);
|
|
return 0;
|
|
}
|
|
|
|
static void r5c_recovery_flush_data_only_stripes(struct r5l_log *log,
|
|
struct r5l_recovery_ctx *ctx)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct r5conf *conf = mddev->private;
|
|
struct stripe_head *sh, *next;
|
|
|
|
if (ctx->data_only_stripes == 0)
|
|
return;
|
|
|
|
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_BACK;
|
|
|
|
list_for_each_entry_safe(sh, next, &ctx->cached_list, lru) {
|
|
r5c_make_stripe_write_out(sh);
|
|
set_bit(STRIPE_HANDLE, &sh->state);
|
|
list_del_init(&sh->lru);
|
|
raid5_release_stripe(sh);
|
|
}
|
|
|
|
md_wakeup_thread(conf->mddev->thread);
|
|
/* reuse conf->wait_for_quiescent in recovery */
|
|
wait_event(conf->wait_for_quiescent,
|
|
atomic_read(&conf->active_stripes) == 0);
|
|
|
|
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
|
|
}
|
|
|
|
static int r5l_recovery_log(struct r5l_log *log)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
struct r5l_recovery_ctx ctx;
|
|
int ret;
|
|
sector_t pos;
|
|
|
|
ctx.pos = log->last_checkpoint;
|
|
ctx.seq = log->last_cp_seq;
|
|
ctx.meta_page = alloc_page(GFP_KERNEL);
|
|
ctx.data_only_stripes = 0;
|
|
ctx.data_parity_stripes = 0;
|
|
INIT_LIST_HEAD(&ctx.cached_list);
|
|
|
|
if (!ctx.meta_page)
|
|
return -ENOMEM;
|
|
|
|
ret = r5c_recovery_flush_log(log, &ctx);
|
|
__free_page(ctx.meta_page);
|
|
|
|
if (ret)
|
|
return ret;
|
|
|
|
pos = ctx.pos;
|
|
ctx.seq += 10000;
|
|
|
|
|
|
if ((ctx.data_only_stripes == 0) && (ctx.data_parity_stripes == 0))
|
|
pr_debug("md/raid:%s: starting from clean shutdown\n",
|
|
mdname(mddev));
|
|
else
|
|
pr_debug("md/raid:%s: recovering %d data-only stripes and %d data-parity stripes\n",
|
|
mdname(mddev), ctx.data_only_stripes,
|
|
ctx.data_parity_stripes);
|
|
|
|
if (ctx.data_only_stripes == 0) {
|
|
log->next_checkpoint = ctx.pos;
|
|
r5l_log_write_empty_meta_block(log, ctx.pos, ctx.seq++);
|
|
ctx.pos = r5l_ring_add(log, ctx.pos, BLOCK_SECTORS);
|
|
} else if (r5c_recovery_rewrite_data_only_stripes(log, &ctx)) {
|
|
pr_err("md/raid:%s: failed to rewrite stripes to journal\n",
|
|
mdname(mddev));
|
|
return -EIO;
|
|
}
|
|
|
|
log->log_start = ctx.pos;
|
|
log->seq = ctx.seq;
|
|
log->last_checkpoint = pos;
|
|
r5l_write_super(log, pos);
|
|
|
|
r5c_recovery_flush_data_only_stripes(log, &ctx);
|
|
return 0;
|
|
}
|
|
|
|
static void r5l_write_super(struct r5l_log *log, sector_t cp)
|
|
{
|
|
struct mddev *mddev = log->rdev->mddev;
|
|
|
|
log->rdev->journal_tail = cp;
|
|
set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
|
|
}
|
|
|
|
static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page)
|
|
{
|
|
struct r5conf *conf = mddev->private;
|
|
int ret;
|
|
|
|
if (!conf->log)
|
|
return 0;
|
|
|
|
switch (conf->log->r5c_journal_mode) {
|
|
case R5C_JOURNAL_MODE_WRITE_THROUGH:
|
|
ret = snprintf(
|
|
page, PAGE_SIZE, "[%s] %s\n",
|
|
r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_THROUGH],
|
|
r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_BACK]);
|
|
break;
|
|
case R5C_JOURNAL_MODE_WRITE_BACK:
|
|
ret = snprintf(
|
|
page, PAGE_SIZE, "%s [%s]\n",
|
|
r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_THROUGH],
|
|
r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_BACK]);
|
|
break;
|
|
default:
|
|
ret = 0;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t r5c_journal_mode_store(struct mddev *mddev,
|
|
const char *page, size_t length)
|
|
{
|
|
struct r5conf *conf = mddev->private;
|
|
struct r5l_log *log = conf->log;
|
|
int val = -1, i;
|
|
int len = length;
|
|
|
|
if (!log)
|
|
return -ENODEV;
|
|
|
|
if (len && page[len - 1] == '\n')
|
|
len -= 1;
|
|
for (i = 0; i < ARRAY_SIZE(r5c_journal_mode_str); i++)
|
|
if (strlen(r5c_journal_mode_str[i]) == len &&
|
|
strncmp(page, r5c_journal_mode_str[i], len) == 0) {
|
|
val = i;
|
|
break;
|
|
}
|
|
if (val < R5C_JOURNAL_MODE_WRITE_THROUGH ||
|
|
val > R5C_JOURNAL_MODE_WRITE_BACK)
|
|
return -EINVAL;
|
|
|
|
if (raid5_calc_degraded(conf) > 0 &&
|
|
val == R5C_JOURNAL_MODE_WRITE_BACK)
|
|
return -EINVAL;
|
|
|
|
mddev_suspend(mddev);
|
|
conf->log->r5c_journal_mode = val;
|
|
mddev_resume(mddev);
|
|
|
|
pr_debug("md/raid:%s: setting r5c cache mode to %d: %s\n",
|
|
mdname(mddev), val, r5c_journal_mode_str[val]);
|
|
return length;
|
|
}
|
|
|
|
struct md_sysfs_entry
|
|
r5c_journal_mode = __ATTR(journal_mode, 0644,
|
|
r5c_journal_mode_show, r5c_journal_mode_store);
|
|
|
|
/*
|
|
* Try handle write operation in caching phase. This function should only
|
|
* be called in write-back mode.
|
|
*
|
|
* If all outstanding writes can be handled in caching phase, returns 0
|
|
* If writes requires write-out phase, call r5c_make_stripe_write_out()
|
|
* and returns -EAGAIN
|
|
*/
|
|
int r5c_try_caching_write(struct r5conf *conf,
|
|
struct stripe_head *sh,
|
|
struct stripe_head_state *s,
|
|
int disks)
|
|
{
|
|
struct r5l_log *log = conf->log;
|
|
int i;
|
|
struct r5dev *dev;
|
|
int to_cache = 0;
|
|
|
|
BUG_ON(!r5c_is_writeback(log));
|
|
|
|
if (!test_bit(STRIPE_R5C_CACHING, &sh->state)) {
|
|
/*
|
|
* There are two different scenarios here:
|
|
* 1. The stripe has some data cached, and it is sent to
|
|
* write-out phase for reclaim
|
|
* 2. The stripe is clean, and this is the first write
|
|
*
|
|
* For 1, return -EAGAIN, so we continue with
|
|
* handle_stripe_dirtying().
|
|
*
|
|
* For 2, set STRIPE_R5C_CACHING and continue with caching
|
|
* write.
|
|
*/
|
|
|
|
/* case 1: anything injournal or anything in written */
|
|
if (s->injournal > 0 || s->written > 0)
|
|
return -EAGAIN;
|
|
/* case 2 */
|
|
set_bit(STRIPE_R5C_CACHING, &sh->state);
|
|
}
|
|
|
|
/*
|
|
* When run in degraded mode, array is set to write-through mode.
|
|
* This check helps drain pending write safely in the transition to
|
|
* write-through mode.
|
|
*/
|
|
if (s->failed) {
|
|
r5c_make_stripe_write_out(sh);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
for (i = disks; i--; ) {
|
|
dev = &sh->dev[i];
|
|
/* if non-overwrite, use writing-out phase */
|
|
if (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags) &&
|
|
!test_bit(R5_InJournal, &dev->flags)) {
|
|
r5c_make_stripe_write_out(sh);
|
|
return -EAGAIN;
|
|
}
|
|
}
|
|
|
|
for (i = disks; i--; ) {
|
|
dev = &sh->dev[i];
|
|
if (dev->towrite) {
|
|
set_bit(R5_Wantwrite, &dev->flags);
|
|
set_bit(R5_Wantdrain, &dev->flags);
|
|
set_bit(R5_LOCKED, &dev->flags);
|
|
to_cache++;
|
|
}
|
|
}
|
|
|
|
if (to_cache) {
|
|
set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
|
|
/*
|
|
* set STRIPE_LOG_TRAPPED, which triggers r5c_cache_data()
|
|
* in ops_run_io(). STRIPE_LOG_TRAPPED will be cleared in
|
|
* r5c_handle_data_cached()
|
|
*/
|
|
set_bit(STRIPE_LOG_TRAPPED, &sh->state);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* free extra pages (orig_page) we allocated for prexor
|
|
*/
|
|
void r5c_release_extra_page(struct stripe_head *sh)
|
|
{
|
|
struct r5conf *conf = sh->raid_conf;
|
|
int i;
|
|
bool using_disk_info_extra_page;
|
|
|
|
using_disk_info_extra_page =
|
|
sh->dev[0].orig_page == conf->disks[0].extra_page;
|
|
|
|
for (i = sh->disks; i--; )
|
|
if (sh->dev[i].page != sh->dev[i].orig_page) {
|
|
struct page *p = sh->dev[i].orig_page;
|
|
|
|
sh->dev[i].orig_page = sh->dev[i].page;
|
|
clear_bit(R5_OrigPageUPTDODATE, &sh->dev[i].flags);
|
|
|
|
if (!using_disk_info_extra_page)
|
|
put_page(p);
|
|
}
|
|
|
|
if (using_disk_info_extra_page) {
|
|
clear_bit(R5C_EXTRA_PAGE_IN_USE, &conf->cache_state);
|
|
md_wakeup_thread(conf->mddev->thread);
|
|
}
|
|
}
|
|
|
|
void r5c_use_extra_page(struct stripe_head *sh)
|
|
{
|
|
struct r5conf *conf = sh->raid_conf;
|
|
int i;
|
|
struct r5dev *dev;
|
|
|
|
for (i = sh->disks; i--; ) {
|
|
dev = &sh->dev[i];
|
|
if (dev->orig_page != dev->page)
|
|
put_page(dev->orig_page);
|
|
dev->orig_page = conf->disks[i].extra_page;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* clean up the stripe (clear R5_InJournal for dev[pd_idx] etc.) after the
|
|
* stripe is committed to RAID disks.
|
|
*/
|
|
void r5c_finish_stripe_write_out(struct r5conf *conf,
|
|
struct stripe_head *sh,
|
|
struct stripe_head_state *s)
|
|
{
|
|
int i;
|
|
int do_wakeup = 0;
|
|
|
|
if (!conf->log ||
|
|
!test_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags))
|
|
return;
|
|
|
|
WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state));
|
|
clear_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags);
|
|
|
|
if (conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
|
|
return;
|
|
|
|
for (i = sh->disks; i--; ) {
|
|
clear_bit(R5_InJournal, &sh->dev[i].flags);
|
|
if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
|
|
do_wakeup = 1;
|
|
}
|
|
|
|
/*
|
|
* analyse_stripe() runs before r5c_finish_stripe_write_out(),
|
|
* We updated R5_InJournal, so we also update s->injournal.
|
|
*/
|
|
s->injournal = 0;
|
|
|
|
if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
|
|
if (atomic_dec_and_test(&conf->pending_full_writes))
|
|
md_wakeup_thread(conf->mddev->thread);
|
|
|
|
if (do_wakeup)
|
|
wake_up(&conf->wait_for_overlap);
|
|
|
|
spin_lock_irq(&conf->log->stripe_in_journal_lock);
|
|
list_del_init(&sh->r5c);
|
|
spin_unlock_irq(&conf->log->stripe_in_journal_lock);
|
|
sh->log_start = MaxSector;
|
|
atomic_dec(&conf->log->stripe_in_journal_count);
|
|
r5c_update_log_state(conf->log);
|
|
}
|
|
|
|
int
|
|
r5c_cache_data(struct r5l_log *log, struct stripe_head *sh,
|
|
struct stripe_head_state *s)
|
|
{
|
|
struct r5conf *conf = sh->raid_conf;
|
|
int pages = 0;
|
|
int reserve;
|
|
int i;
|
|
int ret = 0;
|
|
|
|
BUG_ON(!log);
|
|
|
|
for (i = 0; i < sh->disks; i++) {
|
|
void *addr;
|
|
|
|
if (!test_bit(R5_Wantwrite, &sh->dev[i].flags))
|
|
continue;
|
|
addr = kmap_atomic(sh->dev[i].page);
|
|
sh->dev[i].log_checksum = crc32c_le(log->uuid_checksum,
|
|
addr, PAGE_SIZE);
|
|
kunmap_atomic(addr);
|
|
pages++;
|
|
}
|
|
WARN_ON(pages == 0);
|
|
|
|
/*
|
|
* The stripe must enter state machine again to call endio, so
|
|
* don't delay.
|
|
*/
|
|
clear_bit(STRIPE_DELAYED, &sh->state);
|
|
atomic_inc(&sh->count);
|
|
|
|
mutex_lock(&log->io_mutex);
|
|
/* meta + data */
|
|
reserve = (1 + pages) << (PAGE_SHIFT - 9);
|
|
|
|
if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) &&
|
|
sh->log_start == MaxSector)
|
|
r5l_add_no_space_stripe(log, sh);
|
|
else if (!r5l_has_free_space(log, reserve)) {
|
|
if (sh->log_start == log->last_checkpoint)
|
|
BUG();
|
|
else
|
|
r5l_add_no_space_stripe(log, sh);
|
|
} else {
|
|
ret = r5l_log_stripe(log, sh, pages, 0);
|
|
if (ret) {
|
|
spin_lock_irq(&log->io_list_lock);
|
|
list_add_tail(&sh->log_list, &log->no_mem_stripes);
|
|
spin_unlock_irq(&log->io_list_lock);
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&log->io_mutex);
|
|
return 0;
|
|
}
|
|
|
|
static int r5l_load_log(struct r5l_log *log)
|
|
{
|
|
struct md_rdev *rdev = log->rdev;
|
|
struct page *page;
|
|
struct r5l_meta_block *mb;
|
|
sector_t cp = log->rdev->journal_tail;
|
|
u32 stored_crc, expected_crc;
|
|
bool create_super = false;
|
|
int ret = 0;
|
|
|
|
/* Make sure it's valid */
|
|
if (cp >= rdev->sectors || round_down(cp, BLOCK_SECTORS) != cp)
|
|
cp = 0;
|
|
page = alloc_page(GFP_KERNEL);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
if (!sync_page_io(rdev, cp, PAGE_SIZE, page, REQ_OP_READ, 0, false)) {
|
|
ret = -EIO;
|
|
goto ioerr;
|
|
}
|
|
mb = page_address(page);
|
|
|
|
if (le32_to_cpu(mb->magic) != R5LOG_MAGIC ||
|
|
mb->version != R5LOG_VERSION) {
|
|
create_super = true;
|
|
goto create;
|
|
}
|
|
stored_crc = le32_to_cpu(mb->checksum);
|
|
mb->checksum = 0;
|
|
expected_crc = crc32c_le(log->uuid_checksum, mb, PAGE_SIZE);
|
|
if (stored_crc != expected_crc) {
|
|
create_super = true;
|
|
goto create;
|
|
}
|
|
if (le64_to_cpu(mb->position) != cp) {
|
|
create_super = true;
|
|
goto create;
|
|
}
|
|
create:
|
|
if (create_super) {
|
|
log->last_cp_seq = prandom_u32();
|
|
cp = 0;
|
|
r5l_log_write_empty_meta_block(log, cp, log->last_cp_seq);
|
|
/*
|
|
* Make sure super points to correct address. Log might have
|
|
* data very soon. If super hasn't correct log tail address,
|
|
* recovery can't find the log
|
|
*/
|
|
r5l_write_super(log, cp);
|
|
} else
|
|
log->last_cp_seq = le64_to_cpu(mb->seq);
|
|
|
|
log->device_size = round_down(rdev->sectors, BLOCK_SECTORS);
|
|
log->max_free_space = log->device_size >> RECLAIM_MAX_FREE_SPACE_SHIFT;
|
|
if (log->max_free_space > RECLAIM_MAX_FREE_SPACE)
|
|
log->max_free_space = RECLAIM_MAX_FREE_SPACE;
|
|
log->last_checkpoint = cp;
|
|
|
|
__free_page(page);
|
|
|
|
if (create_super) {
|
|
log->log_start = r5l_ring_add(log, cp, BLOCK_SECTORS);
|
|
log->seq = log->last_cp_seq + 1;
|
|
log->next_checkpoint = cp;
|
|
} else
|
|
ret = r5l_recovery_log(log);
|
|
|
|
r5c_update_log_state(log);
|
|
return ret;
|
|
ioerr:
|
|
__free_page(page);
|
|
return ret;
|
|
}
|
|
|
|
void r5c_update_on_rdev_error(struct mddev *mddev)
|
|
{
|
|
struct r5conf *conf = mddev->private;
|
|
struct r5l_log *log = conf->log;
|
|
|
|
if (!log)
|
|
return;
|
|
|
|
if (raid5_calc_degraded(conf) > 0 &&
|
|
conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK)
|
|
schedule_work(&log->disable_writeback_work);
|
|
}
|
|
|
|
int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
|
|
{
|
|
struct request_queue *q = bdev_get_queue(rdev->bdev);
|
|
struct r5l_log *log;
|
|
|
|
if (PAGE_SIZE != 4096)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* The PAGE_SIZE must be big enough to hold 1 r5l_meta_block and
|
|
* raid_disks r5l_payload_data_parity.
|
|
*
|
|
* Write journal and cache does not work for very big array
|
|
* (raid_disks > 203)
|
|
*/
|
|
if (sizeof(struct r5l_meta_block) +
|
|
((sizeof(struct r5l_payload_data_parity) + sizeof(__le32)) *
|
|
conf->raid_disks) > PAGE_SIZE) {
|
|
pr_err("md/raid:%s: write journal/cache doesn't work for array with %d disks\n",
|
|
mdname(conf->mddev), conf->raid_disks);
|
|
return -EINVAL;
|
|
}
|
|
|
|
log = kzalloc(sizeof(*log), GFP_KERNEL);
|
|
if (!log)
|
|
return -ENOMEM;
|
|
log->rdev = rdev;
|
|
|
|
log->need_cache_flush = test_bit(QUEUE_FLAG_WC, &q->queue_flags) != 0;
|
|
|
|
log->uuid_checksum = crc32c_le(~0, rdev->mddev->uuid,
|
|
sizeof(rdev->mddev->uuid));
|
|
|
|
mutex_init(&log->io_mutex);
|
|
|
|
spin_lock_init(&log->io_list_lock);
|
|
INIT_LIST_HEAD(&log->running_ios);
|
|
INIT_LIST_HEAD(&log->io_end_ios);
|
|
INIT_LIST_HEAD(&log->flushing_ios);
|
|
INIT_LIST_HEAD(&log->finished_ios);
|
|
bio_init(&log->flush_bio, NULL, 0);
|
|
|
|
log->io_kc = KMEM_CACHE(r5l_io_unit, 0);
|
|
if (!log->io_kc)
|
|
goto io_kc;
|
|
|
|
log->io_pool = mempool_create_slab_pool(R5L_POOL_SIZE, log->io_kc);
|
|
if (!log->io_pool)
|
|
goto io_pool;
|
|
|
|
log->bs = bioset_create(R5L_POOL_SIZE, 0);
|
|
if (!log->bs)
|
|
goto io_bs;
|
|
|
|
log->meta_pool = mempool_create_page_pool(R5L_POOL_SIZE, 0);
|
|
if (!log->meta_pool)
|
|
goto out_mempool;
|
|
|
|
log->reclaim_thread = md_register_thread(r5l_reclaim_thread,
|
|
log->rdev->mddev, "reclaim");
|
|
if (!log->reclaim_thread)
|
|
goto reclaim_thread;
|
|
log->reclaim_thread->timeout = R5C_RECLAIM_WAKEUP_INTERVAL;
|
|
|
|
init_waitqueue_head(&log->iounit_wait);
|
|
|
|
INIT_LIST_HEAD(&log->no_mem_stripes);
|
|
|
|
INIT_LIST_HEAD(&log->no_space_stripes);
|
|
spin_lock_init(&log->no_space_stripes_lock);
|
|
|
|
INIT_WORK(&log->deferred_io_work, r5l_submit_io_async);
|
|
INIT_WORK(&log->disable_writeback_work, r5c_disable_writeback_async);
|
|
|
|
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
|
|
INIT_LIST_HEAD(&log->stripe_in_journal_list);
|
|
spin_lock_init(&log->stripe_in_journal_lock);
|
|
atomic_set(&log->stripe_in_journal_count, 0);
|
|
|
|
rcu_assign_pointer(conf->log, log);
|
|
|
|
if (r5l_load_log(log))
|
|
goto error;
|
|
|
|
set_bit(MD_HAS_JOURNAL, &conf->mddev->flags);
|
|
return 0;
|
|
|
|
error:
|
|
rcu_assign_pointer(conf->log, NULL);
|
|
md_unregister_thread(&log->reclaim_thread);
|
|
reclaim_thread:
|
|
mempool_destroy(log->meta_pool);
|
|
out_mempool:
|
|
bioset_free(log->bs);
|
|
io_bs:
|
|
mempool_destroy(log->io_pool);
|
|
io_pool:
|
|
kmem_cache_destroy(log->io_kc);
|
|
io_kc:
|
|
kfree(log);
|
|
return -EINVAL;
|
|
}
|
|
|
|
void r5l_exit_log(struct r5l_log *log)
|
|
{
|
|
flush_work(&log->disable_writeback_work);
|
|
md_unregister_thread(&log->reclaim_thread);
|
|
mempool_destroy(log->meta_pool);
|
|
bioset_free(log->bs);
|
|
mempool_destroy(log->io_pool);
|
|
kmem_cache_destroy(log->io_kc);
|
|
kfree(log);
|
|
}
|