swh:1:snp:38ae39f9fd01a4b0ef06fab5668b65bf4c2aca03
Tip revision: c9e6606c7fe92b50a02ce51dda82586ebdf99b48 authored by Linus Torvalds on 02 January 2022, 22:23:25 UTC
Linux 5.16-rc8
Linux 5.16-rc8
Tip revision: c9e6606
queue.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2003 Russell King, All Rights Reserved.
* Copyright 2006-2007 Pierre Ossman
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/freezer.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/backing-dev.h>
#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include "queue.h"
#include "block.h"
#include "core.h"
#include "card.h"
#include "crypto.h"
#include "host.h"
#define MMC_DMA_MAP_MERGE_SEGMENTS 512
static inline bool mmc_cqe_dcmd_busy(struct mmc_queue *mq)
{
/* Allow only 1 DCMD at a time */
return mq->in_flight[MMC_ISSUE_DCMD];
}
void mmc_cqe_check_busy(struct mmc_queue *mq)
{
if ((mq->cqe_busy & MMC_CQE_DCMD_BUSY) && !mmc_cqe_dcmd_busy(mq))
mq->cqe_busy &= ~MMC_CQE_DCMD_BUSY;
}
static inline bool mmc_cqe_can_dcmd(struct mmc_host *host)
{
return host->caps2 & MMC_CAP2_CQE_DCMD;
}
static enum mmc_issue_type mmc_cqe_issue_type(struct mmc_host *host,
struct request *req)
{
switch (req_op(req)) {
case REQ_OP_DRV_IN:
case REQ_OP_DRV_OUT:
case REQ_OP_DISCARD:
case REQ_OP_SECURE_ERASE:
return MMC_ISSUE_SYNC;
case REQ_OP_FLUSH:
return mmc_cqe_can_dcmd(host) ? MMC_ISSUE_DCMD : MMC_ISSUE_SYNC;
default:
return MMC_ISSUE_ASYNC;
}
}
enum mmc_issue_type mmc_issue_type(struct mmc_queue *mq, struct request *req)
{
struct mmc_host *host = mq->card->host;
if (host->cqe_enabled && !host->hsq_enabled)
return mmc_cqe_issue_type(host, req);
if (req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_WRITE)
return MMC_ISSUE_ASYNC;
return MMC_ISSUE_SYNC;
}
static void __mmc_cqe_recovery_notifier(struct mmc_queue *mq)
{
if (!mq->recovery_needed) {
mq->recovery_needed = true;
schedule_work(&mq->recovery_work);
}
}
void mmc_cqe_recovery_notifier(struct mmc_request *mrq)
{
struct mmc_queue_req *mqrq = container_of(mrq, struct mmc_queue_req,
brq.mrq);
struct request *req = mmc_queue_req_to_req(mqrq);
struct request_queue *q = req->q;
struct mmc_queue *mq = q->queuedata;
unsigned long flags;
spin_lock_irqsave(&mq->lock, flags);
__mmc_cqe_recovery_notifier(mq);
spin_unlock_irqrestore(&mq->lock, flags);
}
static enum blk_eh_timer_return mmc_cqe_timed_out(struct request *req)
{
struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req);
struct mmc_request *mrq = &mqrq->brq.mrq;
struct mmc_queue *mq = req->q->queuedata;
struct mmc_host *host = mq->card->host;
enum mmc_issue_type issue_type = mmc_issue_type(mq, req);
bool recovery_needed = false;
switch (issue_type) {
case MMC_ISSUE_ASYNC:
case MMC_ISSUE_DCMD:
if (host->cqe_ops->cqe_timeout(host, mrq, &recovery_needed)) {
if (recovery_needed)
mmc_cqe_recovery_notifier(mrq);
return BLK_EH_RESET_TIMER;
}
/* The request has gone already */
return BLK_EH_DONE;
default:
/* Timeout is handled by mmc core */
return BLK_EH_RESET_TIMER;
}
}
static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req,
bool reserved)
{
struct request_queue *q = req->q;
struct mmc_queue *mq = q->queuedata;
struct mmc_card *card = mq->card;
struct mmc_host *host = card->host;
unsigned long flags;
bool ignore_tout;
spin_lock_irqsave(&mq->lock, flags);
ignore_tout = mq->recovery_needed || !host->cqe_enabled || host->hsq_enabled;
spin_unlock_irqrestore(&mq->lock, flags);
return ignore_tout ? BLK_EH_RESET_TIMER : mmc_cqe_timed_out(req);
}
static void mmc_mq_recovery_handler(struct work_struct *work)
{
struct mmc_queue *mq = container_of(work, struct mmc_queue,
recovery_work);
struct request_queue *q = mq->queue;
struct mmc_host *host = mq->card->host;
mmc_get_card(mq->card, &mq->ctx);
mq->in_recovery = true;
if (host->cqe_enabled && !host->hsq_enabled)
mmc_blk_cqe_recovery(mq);
else
mmc_blk_mq_recovery(mq);
mq->in_recovery = false;
spin_lock_irq(&mq->lock);
mq->recovery_needed = false;
spin_unlock_irq(&mq->lock);
if (host->hsq_enabled)
host->cqe_ops->cqe_recovery_finish(host);
mmc_put_card(mq->card, &mq->ctx);
blk_mq_run_hw_queues(q, true);
}
static struct scatterlist *mmc_alloc_sg(unsigned short sg_len, gfp_t gfp)
{
struct scatterlist *sg;
sg = kmalloc_array(sg_len, sizeof(*sg), gfp);
if (sg)
sg_init_table(sg, sg_len);
return sg;
}
static void mmc_queue_setup_discard(struct request_queue *q,
struct mmc_card *card)
{
unsigned max_discard;
max_discard = mmc_calc_max_discard(card);
if (!max_discard)
return;
blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
blk_queue_max_discard_sectors(q, max_discard);
q->limits.discard_granularity = card->pref_erase << 9;
/* granularity must not be greater than max. discard */
if (card->pref_erase > max_discard)
q->limits.discard_granularity = SECTOR_SIZE;
if (mmc_can_secure_erase_trim(card))
blk_queue_flag_set(QUEUE_FLAG_SECERASE, q);
}
static unsigned short mmc_get_max_segments(struct mmc_host *host)
{
return host->can_dma_map_merge ? MMC_DMA_MAP_MERGE_SEGMENTS :
host->max_segs;
}
static int mmc_mq_init_request(struct blk_mq_tag_set *set, struct request *req,
unsigned int hctx_idx, unsigned int numa_node)
{
struct mmc_queue_req *mq_rq = req_to_mmc_queue_req(req);
struct mmc_queue *mq = set->driver_data;
struct mmc_card *card = mq->card;
struct mmc_host *host = card->host;
mq_rq->sg = mmc_alloc_sg(mmc_get_max_segments(host), GFP_KERNEL);
if (!mq_rq->sg)
return -ENOMEM;
return 0;
}
static void mmc_mq_exit_request(struct blk_mq_tag_set *set, struct request *req,
unsigned int hctx_idx)
{
struct mmc_queue_req *mq_rq = req_to_mmc_queue_req(req);
kfree(mq_rq->sg);
mq_rq->sg = NULL;
}
static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct request *req = bd->rq;
struct request_queue *q = req->q;
struct mmc_queue *mq = q->queuedata;
struct mmc_card *card = mq->card;
struct mmc_host *host = card->host;
enum mmc_issue_type issue_type;
enum mmc_issued issued;
bool get_card, cqe_retune_ok;
int ret;
if (mmc_card_removed(mq->card)) {
req->rq_flags |= RQF_QUIET;
return BLK_STS_IOERR;
}
issue_type = mmc_issue_type(mq, req);
spin_lock_irq(&mq->lock);
if (mq->recovery_needed || mq->busy) {
spin_unlock_irq(&mq->lock);
return BLK_STS_RESOURCE;
}
switch (issue_type) {
case MMC_ISSUE_DCMD:
if (mmc_cqe_dcmd_busy(mq)) {
mq->cqe_busy |= MMC_CQE_DCMD_BUSY;
spin_unlock_irq(&mq->lock);
return BLK_STS_RESOURCE;
}
break;
case MMC_ISSUE_ASYNC:
/*
* For MMC host software queue, we only allow 2 requests in
* flight to avoid a long latency.
*/
if (host->hsq_enabled && mq->in_flight[issue_type] > 2) {
spin_unlock_irq(&mq->lock);
return BLK_STS_RESOURCE;
}
break;
default:
/*
* Timeouts are handled by mmc core, and we don't have a host
* API to abort requests, so we can't handle the timeout anyway.
* However, when the timeout happens, blk_mq_complete_request()
* no longer works (to stop the request disappearing under us).
* To avoid racing with that, set a large timeout.
*/
req->timeout = 600 * HZ;
break;
}
/* Parallel dispatch of requests is not supported at the moment */
mq->busy = true;
mq->in_flight[issue_type] += 1;
get_card = (mmc_tot_in_flight(mq) == 1);
cqe_retune_ok = (mmc_cqe_qcnt(mq) == 1);
spin_unlock_irq(&mq->lock);
if (!(req->rq_flags & RQF_DONTPREP)) {
req_to_mmc_queue_req(req)->retries = 0;
req->rq_flags |= RQF_DONTPREP;
}
if (get_card)
mmc_get_card(card, &mq->ctx);
if (host->cqe_enabled) {
host->retune_now = host->need_retune && cqe_retune_ok &&
!host->hold_retune;
}
blk_mq_start_request(req);
issued = mmc_blk_mq_issue_rq(mq, req);
switch (issued) {
case MMC_REQ_BUSY:
ret = BLK_STS_RESOURCE;
break;
case MMC_REQ_FAILED_TO_START:
ret = BLK_STS_IOERR;
break;
default:
ret = BLK_STS_OK;
break;
}
if (issued != MMC_REQ_STARTED) {
bool put_card = false;
spin_lock_irq(&mq->lock);
mq->in_flight[issue_type] -= 1;
if (mmc_tot_in_flight(mq) == 0)
put_card = true;
mq->busy = false;
spin_unlock_irq(&mq->lock);
if (put_card)
mmc_put_card(card, &mq->ctx);
} else {
WRITE_ONCE(mq->busy, false);
}
return ret;
}
static const struct blk_mq_ops mmc_mq_ops = {
.queue_rq = mmc_mq_queue_rq,
.init_request = mmc_mq_init_request,
.exit_request = mmc_mq_exit_request,
.complete = mmc_blk_mq_complete,
.timeout = mmc_mq_timed_out,
};
static void mmc_setup_queue(struct mmc_queue *mq, struct mmc_card *card)
{
struct mmc_host *host = card->host;
unsigned block_size = 512;
blk_queue_flag_set(QUEUE_FLAG_NONROT, mq->queue);
blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, mq->queue);
if (mmc_can_erase(card))
mmc_queue_setup_discard(mq->queue, card);
if (!mmc_dev(host)->dma_mask || !*mmc_dev(host)->dma_mask)
blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_HIGH);
blk_queue_max_hw_sectors(mq->queue,
min(host->max_blk_count, host->max_req_size / 512));
if (host->can_dma_map_merge)
WARN(!blk_queue_can_use_dma_map_merging(mq->queue,
mmc_dev(host)),
"merging was advertised but not possible");
blk_queue_max_segments(mq->queue, mmc_get_max_segments(host));
if (mmc_card_mmc(card) && card->ext_csd.data_sector_size) {
block_size = card->ext_csd.data_sector_size;
WARN_ON(block_size != 512 && block_size != 4096);
}
blk_queue_logical_block_size(mq->queue, block_size);
/*
* After blk_queue_can_use_dma_map_merging() was called with succeed,
* since it calls blk_queue_virt_boundary(), the mmc should not call
* both blk_queue_max_segment_size().
*/
if (!host->can_dma_map_merge)
blk_queue_max_segment_size(mq->queue,
round_down(host->max_seg_size, block_size));
dma_set_max_seg_size(mmc_dev(host), queue_max_segment_size(mq->queue));
INIT_WORK(&mq->recovery_work, mmc_mq_recovery_handler);
INIT_WORK(&mq->complete_work, mmc_blk_mq_complete_work);
mutex_init(&mq->complete_lock);
init_waitqueue_head(&mq->wait);
mmc_crypto_setup_queue(mq->queue, host);
}
static inline bool mmc_merge_capable(struct mmc_host *host)
{
return host->caps2 & MMC_CAP2_MERGE_CAPABLE;
}
/* Set queue depth to get a reasonable value for q->nr_requests */
#define MMC_QUEUE_DEPTH 64
/**
* mmc_init_queue - initialise a queue structure.
* @mq: mmc queue
* @card: mmc card to attach this queue
*
* Initialise a MMC card request queue.
*/
struct gendisk *mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
{
struct mmc_host *host = card->host;
struct gendisk *disk;
int ret;
mq->card = card;
spin_lock_init(&mq->lock);
memset(&mq->tag_set, 0, sizeof(mq->tag_set));
mq->tag_set.ops = &mmc_mq_ops;
/*
* The queue depth for CQE must match the hardware because the request
* tag is used to index the hardware queue.
*/
if (host->cqe_enabled && !host->hsq_enabled)
mq->tag_set.queue_depth =
min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth);
else
mq->tag_set.queue_depth = MMC_QUEUE_DEPTH;
mq->tag_set.numa_node = NUMA_NO_NODE;
mq->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING;
mq->tag_set.nr_hw_queues = 1;
mq->tag_set.cmd_size = sizeof(struct mmc_queue_req);
mq->tag_set.driver_data = mq;
/*
* Since blk_mq_alloc_tag_set() calls .init_request() of mmc_mq_ops,
* the host->can_dma_map_merge should be set before to get max_segs
* from mmc_get_max_segments().
*/
if (mmc_merge_capable(host) &&
host->max_segs < MMC_DMA_MAP_MERGE_SEGMENTS &&
dma_get_merge_boundary(mmc_dev(host)))
host->can_dma_map_merge = 1;
else
host->can_dma_map_merge = 0;
ret = blk_mq_alloc_tag_set(&mq->tag_set);
if (ret)
return ERR_PTR(ret);
disk = blk_mq_alloc_disk(&mq->tag_set, mq);
if (IS_ERR(disk)) {
blk_mq_free_tag_set(&mq->tag_set);
return disk;
}
mq->queue = disk->queue;
if (mmc_host_is_spi(host) && host->use_spi_crc)
blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, mq->queue);
blk_queue_rq_timeout(mq->queue, 60 * HZ);
mmc_setup_queue(mq, card);
return disk;
}
void mmc_queue_suspend(struct mmc_queue *mq)
{
blk_mq_quiesce_queue(mq->queue);
/*
* The host remains claimed while there are outstanding requests, so
* simply claiming and releasing here ensures there are none.
*/
mmc_claim_host(mq->card->host);
mmc_release_host(mq->card->host);
}
void mmc_queue_resume(struct mmc_queue *mq)
{
blk_mq_unquiesce_queue(mq->queue);
}
void mmc_cleanup_queue(struct mmc_queue *mq)
{
struct request_queue *q = mq->queue;
/*
* The legacy code handled the possibility of being suspended,
* so do that here too.
*/
if (blk_queue_quiesced(q))
blk_mq_unquiesce_queue(q);
blk_cleanup_queue(q);
blk_mq_free_tag_set(&mq->tag_set);
/*
* A request can be completed before the next request, potentially
* leaving a complete_work with nothing to do. Such a work item might
* still be queued at this point. Flush it.
*/
flush_work(&mq->complete_work);
mq->card = NULL;
}
/*
* Prepare the sg list(s) to be handed of to the host driver
*/
unsigned int mmc_queue_map_sg(struct mmc_queue *mq, struct mmc_queue_req *mqrq)
{
struct request *req = mmc_queue_req_to_req(mqrq);
return blk_rq_map_sg(mq->queue, req, mqrq->sg);
}