--- /dev/null
+/*
+ * linux/drivers/mmc/card/queue.c
+ *
+ * Copyright (C) 2003 Russell King, All Rights Reserved.
+ * Copyright 2006-2007 Pierre Ossman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+
+#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
+#include "queue.h"
+
+#define MMC_QUEUE_BOUNCESZ 65536
+
+/*
+ * Prepare a MMC request. This just filters out odd stuff.
+ */
+static int mmc_prep_request(struct request_queue *q, struct request *req)
+{
+ struct mmc_queue *mq = q->queuedata;
+
+ /*
+ * We only like normal block requests and discards.
+ */
+ if (req->cmd_type != REQ_TYPE_FS && !(req->cmd_flags & REQ_DISCARD)) {
+ blk_dump_rq_flags(req, "MMC bad request");
+ return BLKPREP_KILL;
+ }
+
+ if (mq && (mmc_card_removed(mq->card) || mmc_access_rpmb(mq)))
+ return BLKPREP_KILL;
+
+ req->cmd_flags |= REQ_DONTPREP;
+
+ return BLKPREP_OK;
+}
+
+static int mmc_queue_thread(void *d)
+{
+ struct mmc_queue *mq = d;
+ struct request_queue *q = mq->queue;
+
+ current->flags |= PF_MEMALLOC;
+
+ down(&mq->thread_sem);
+ do {
+ struct request *req = NULL;
+ struct mmc_queue_req *tmp;
+ unsigned int cmd_flags = 0;
+
+ spin_lock_irq(q->queue_lock);
+ set_current_state(TASK_INTERRUPTIBLE);
+ req = blk_fetch_request(q);
+ mq->mqrq_cur->req = req;
+ spin_unlock_irq(q->queue_lock);
+
+ if (req || mq->mqrq_prev->req) {
+ set_current_state(TASK_RUNNING);
+ cmd_flags = req ? req->cmd_flags : 0;
+ mq->issue_fn(mq, req);
+ if (mq->flags & MMC_QUEUE_NEW_REQUEST) {
+ mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
+ continue; /* fetch again */
+ }
+
+ /*
+ * Current request becomes previous request
+ * and vice versa.
+ * In case of special requests, current request
+ * has been finished. Do not assign it to previous
+ * request.
+ */
+ if (cmd_flags & MMC_REQ_SPECIAL_MASK)
+ mq->mqrq_cur->req = NULL;
+
+ mq->mqrq_prev->brq.mrq.data = NULL;
+ mq->mqrq_prev->req = NULL;
+ tmp = mq->mqrq_prev;
+ mq->mqrq_prev = mq->mqrq_cur;
+ mq->mqrq_cur = tmp;
+ } else {
+ if (kthread_should_stop()) {
+ set_current_state(TASK_RUNNING);
+ break;
+ }
+ up(&mq->thread_sem);
+ schedule();
+ down(&mq->thread_sem);
+ }
+ } while (1);
+ up(&mq->thread_sem);
+
+ return 0;
+}
+
+/*
+ * Generic MMC request handler. This is called for any queue on a
+ * particular host. When the host is not busy, we look for a request
+ * on any queue on this host, and attempt to issue it. This may
+ * not be the queue we were asked to process.
+ */
+static void mmc_request_fn(struct request_queue *q)
+{
+ struct mmc_queue *mq = q->queuedata;
+ struct request *req;
+ unsigned long flags;
+ struct mmc_context_info *cntx;
+
+ if (!mq) {
+ while ((req = blk_fetch_request(q)) != NULL) {
+ req->cmd_flags |= REQ_QUIET;
+ __blk_end_request_all(req, -EIO);
+ }
+ return;
+ }
+
+ cntx = &mq->card->host->context_info;
+ if (!mq->mqrq_cur->req && mq->mqrq_prev->req) {
+ /*
+ * New MMC request arrived when MMC thread may be
+ * blocked on the previous request to be complete
+ * with no current request fetched
+ */
+ spin_lock_irqsave(&cntx->lock, flags);
+ if (cntx->is_waiting_last_req) {
+ cntx->is_new_req = true;
+ wake_up_interruptible(&cntx->wait);
+ }
+ spin_unlock_irqrestore(&cntx->lock, flags);
+ } else if (!mq->mqrq_cur->req && !mq->mqrq_prev->req)
+ wake_up_process(mq->thread);
+}
+
+static struct scatterlist *mmc_alloc_sg(int sg_len, int *err)
+{
+ struct scatterlist *sg;
+
+ sg = kmalloc(sizeof(struct scatterlist)*sg_len, GFP_KERNEL);
+ if (!sg)
+ *err = -ENOMEM;
+ else {
+ *err = 0;
+ 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;
+
+ queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
+ q->limits.max_discard_sectors = max_discard;
+ if (card->erased_byte == 0 && !mmc_can_discard(card))
+ q->limits.discard_zeroes_data = 1;
+ 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 = 0;
+ if (mmc_can_secure_erase_trim(card))
+ queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD, q);
+}
+
+/**
+ * mmc_init_queue - initialise a queue structure.
+ * @mq: mmc queue
+ * @card: mmc card to attach this queue
+ * @lock: queue lock
+ * @subname: partition subname
+ *
+ * Initialise a MMC card request queue.
+ */
+int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
+ spinlock_t *lock, const char *subname)
+{
+ struct mmc_host *host = card->host;
+ u64 limit = BLK_BOUNCE_HIGH;
+ int ret;
+ struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
+ struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
+
+ if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
+ limit = (u64)dma_max_pfn(mmc_dev(host)) << PAGE_SHIFT;
+
+ mq->card = card;
+ mq->queue = blk_init_queue(mmc_request_fn, lock);
+ if (!mq->queue)
+ return -ENOMEM;
+
+ mq->mqrq_cur = mqrq_cur;
+ mq->mqrq_prev = mqrq_prev;
+ mq->queue->queuedata = mq;
+
+ blk_queue_prep_rq(mq->queue, mmc_prep_request);
+ queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue);
+ queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, mq->queue);
+ if (mmc_can_erase(card))
+ mmc_queue_setup_discard(mq->queue, card);
+
+#ifdef CONFIG_MMC_BLOCK_BOUNCE
+ if (host->max_segs == 1) {
+ unsigned int bouncesz;
+
+ bouncesz = MMC_QUEUE_BOUNCESZ;
+
+ if (bouncesz > host->max_req_size)
+ bouncesz = host->max_req_size;
+ if (bouncesz > host->max_seg_size)
+ bouncesz = host->max_seg_size;
+ if (bouncesz > (host->max_blk_count * 512))
+ bouncesz = host->max_blk_count * 512;
+
+ if (bouncesz > 512) {
+ mqrq_cur->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
+ if (!mqrq_cur->bounce_buf) {
+ pr_warn("%s: unable to allocate bounce cur buffer\n",
+ mmc_card_name(card));
+ } else {
+ mqrq_prev->bounce_buf =
+ kmalloc(bouncesz, GFP_KERNEL);
+ if (!mqrq_prev->bounce_buf) {
+ pr_warn("%s: unable to allocate bounce prev buffer\n",
+ mmc_card_name(card));
+ kfree(mqrq_cur->bounce_buf);
+ mqrq_cur->bounce_buf = NULL;
+ }
+ }
+ }
+
+ if (mqrq_cur->bounce_buf && mqrq_prev->bounce_buf) {
+ blk_queue_bounce_limit(mq->queue, BLK_BOUNCE_ANY);
+ blk_queue_max_hw_sectors(mq->queue, bouncesz / 512);
+ blk_queue_max_segments(mq->queue, bouncesz / 512);
+ blk_queue_max_segment_size(mq->queue, bouncesz);
+
+ mqrq_cur->sg = mmc_alloc_sg(1, &ret);
+ if (ret)
+ goto cleanup_queue;
+
+ mqrq_cur->bounce_sg =
+ mmc_alloc_sg(bouncesz / 512, &ret);
+ if (ret)
+ goto cleanup_queue;
+
+ mqrq_prev->sg = mmc_alloc_sg(1, &ret);
+ if (ret)
+ goto cleanup_queue;
+
+ mqrq_prev->bounce_sg =
+ mmc_alloc_sg(bouncesz / 512, &ret);
+ if (ret)
+ goto cleanup_queue;
+ }
+ }
+#endif
+
+ if (!mqrq_cur->bounce_buf && !mqrq_prev->bounce_buf) {
+ blk_queue_bounce_limit(mq->queue, limit);
+ blk_queue_max_hw_sectors(mq->queue,
+ min(host->max_blk_count, host->max_req_size / 512));
+ blk_queue_max_segments(mq->queue, host->max_segs);
+ blk_queue_max_segment_size(mq->queue, host->max_seg_size);
+
+ mqrq_cur->sg = mmc_alloc_sg(host->max_segs, &ret);
+ if (ret)
+ goto cleanup_queue;
+
+
+ mqrq_prev->sg = mmc_alloc_sg(host->max_segs, &ret);
+ if (ret)
+ goto cleanup_queue;
+ }
+
+ sema_init(&mq->thread_sem, 1);
+
+ mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd/%d%s",
+ host->index, subname ? subname : "");
+
+ if (IS_ERR(mq->thread)) {
+ ret = PTR_ERR(mq->thread);
+ goto free_bounce_sg;
+ }
+
+ return 0;
+ free_bounce_sg:
+ kfree(mqrq_cur->bounce_sg);
+ mqrq_cur->bounce_sg = NULL;
+ kfree(mqrq_prev->bounce_sg);
+ mqrq_prev->bounce_sg = NULL;
+
+ cleanup_queue:
+ kfree(mqrq_cur->sg);
+ mqrq_cur->sg = NULL;
+ kfree(mqrq_cur->bounce_buf);
+ mqrq_cur->bounce_buf = NULL;
+
+ kfree(mqrq_prev->sg);
+ mqrq_prev->sg = NULL;
+ kfree(mqrq_prev->bounce_buf);
+ mqrq_prev->bounce_buf = NULL;
+
+ blk_cleanup_queue(mq->queue);
+ return ret;
+}
+
+void mmc_cleanup_queue(struct mmc_queue *mq)
+{
+ struct request_queue *q = mq->queue;
+ unsigned long flags;
+ struct mmc_queue_req *mqrq_cur = mq->mqrq_cur;
+ struct mmc_queue_req *mqrq_prev = mq->mqrq_prev;
+
+ /* Make sure the queue isn't suspended, as that will deadlock */
+ mmc_queue_resume(mq);
+
+ /* Then terminate our worker thread */
+ kthread_stop(mq->thread);
+
+ /* Empty the queue */
+ spin_lock_irqsave(q->queue_lock, flags);
+ q->queuedata = NULL;
+ blk_start_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ kfree(mqrq_cur->bounce_sg);
+ mqrq_cur->bounce_sg = NULL;
+
+ kfree(mqrq_cur->sg);
+ mqrq_cur->sg = NULL;
+
+ kfree(mqrq_cur->bounce_buf);
+ mqrq_cur->bounce_buf = NULL;
+
+ kfree(mqrq_prev->bounce_sg);
+ mqrq_prev->bounce_sg = NULL;
+
+ kfree(mqrq_prev->sg);
+ mqrq_prev->sg = NULL;
+
+ kfree(mqrq_prev->bounce_buf);
+ mqrq_prev->bounce_buf = NULL;
+
+ mq->card = NULL;
+}
+EXPORT_SYMBOL(mmc_cleanup_queue);
+
+int mmc_packed_init(struct mmc_queue *mq, struct mmc_card *card)
+{
+ struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
+ struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
+ int ret = 0;
+
+
+ mqrq_cur->packed = kzalloc(sizeof(struct mmc_packed), GFP_KERNEL);
+ if (!mqrq_cur->packed) {
+ pr_warn("%s: unable to allocate packed cmd for mqrq_cur\n",
+ mmc_card_name(card));
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ mqrq_prev->packed = kzalloc(sizeof(struct mmc_packed), GFP_KERNEL);
+ if (!mqrq_prev->packed) {
+ pr_warn("%s: unable to allocate packed cmd for mqrq_prev\n",
+ mmc_card_name(card));
+ kfree(mqrq_cur->packed);
+ mqrq_cur->packed = NULL;
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ INIT_LIST_HEAD(&mqrq_cur->packed->list);
+ INIT_LIST_HEAD(&mqrq_prev->packed->list);
+
+out:
+ return ret;
+}
+
+void mmc_packed_clean(struct mmc_queue *mq)
+{
+ struct mmc_queue_req *mqrq_cur = &mq->mqrq[0];
+ struct mmc_queue_req *mqrq_prev = &mq->mqrq[1];
+
+ kfree(mqrq_cur->packed);
+ mqrq_cur->packed = NULL;
+ kfree(mqrq_prev->packed);
+ mqrq_prev->packed = NULL;
+}
+
+/**
+ * mmc_queue_suspend - suspend a MMC request queue
+ * @mq: MMC queue to suspend
+ *
+ * Stop the block request queue, and wait for our thread to
+ * complete any outstanding requests. This ensures that we
+ * won't suspend while a request is being processed.
+ */
+void mmc_queue_suspend(struct mmc_queue *mq)
+{
+ struct request_queue *q = mq->queue;
+ unsigned long flags;
+
+ if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
+ mq->flags |= MMC_QUEUE_SUSPENDED;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ blk_stop_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ down(&mq->thread_sem);
+ }
+}
+
+/**
+ * mmc_queue_resume - resume a previously suspended MMC request queue
+ * @mq: MMC queue to resume
+ */
+void mmc_queue_resume(struct mmc_queue *mq)
+{
+ struct request_queue *q = mq->queue;
+ unsigned long flags;
+
+ if (mq->flags & MMC_QUEUE_SUSPENDED) {
+ mq->flags &= ~MMC_QUEUE_SUSPENDED;
+
+ up(&mq->thread_sem);
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ blk_start_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+ }
+}
+
+static unsigned int mmc_queue_packed_map_sg(struct mmc_queue *mq,
+ struct mmc_packed *packed,
+ struct scatterlist *sg,
+ enum mmc_packed_type cmd_type)
+{
+ struct scatterlist *__sg = sg;
+ unsigned int sg_len = 0;
+ struct request *req;
+
+ if (mmc_packed_wr(cmd_type)) {
+ unsigned int hdr_sz = mmc_large_sector(mq->card) ? 4096 : 512;
+ unsigned int max_seg_sz = queue_max_segment_size(mq->queue);
+ unsigned int len, remain, offset = 0;
+ u8 *buf = (u8 *)packed->cmd_hdr;
+
+ remain = hdr_sz;
+ do {
+ len = min(remain, max_seg_sz);
+ sg_set_buf(__sg, buf + offset, len);
+ offset += len;
+ remain -= len;
+ (__sg++)->page_link &= ~0x02;
+ sg_len++;
+ } while (remain);
+ }
+
+ list_for_each_entry(req, &packed->list, queuelist) {
+ sg_len += blk_rq_map_sg(mq->queue, req, __sg);
+ __sg = sg + (sg_len - 1);
+ (__sg++)->page_link &= ~0x02;
+ }
+ sg_mark_end(sg + (sg_len - 1));
+ return sg_len;
+}
+
+/*
+ * 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)
+{
+ unsigned int sg_len;
+ size_t buflen;
+ struct scatterlist *sg;
+ enum mmc_packed_type cmd_type;
+ int i;
+
+ cmd_type = mqrq->cmd_type;
+
+ if (!mqrq->bounce_buf) {
+ if (mmc_packed_cmd(cmd_type))
+ return mmc_queue_packed_map_sg(mq, mqrq->packed,
+ mqrq->sg, cmd_type);
+ else
+ return blk_rq_map_sg(mq->queue, mqrq->req, mqrq->sg);
+ }
+
+ BUG_ON(!mqrq->bounce_sg);
+
+ if (mmc_packed_cmd(cmd_type))
+ sg_len = mmc_queue_packed_map_sg(mq, mqrq->packed,
+ mqrq->bounce_sg, cmd_type);
+ else
+ sg_len = blk_rq_map_sg(mq->queue, mqrq->req, mqrq->bounce_sg);
+
+ mqrq->bounce_sg_len = sg_len;
+
+ buflen = 0;
+ for_each_sg(mqrq->bounce_sg, sg, sg_len, i)
+ buflen += sg->length;
+
+ sg_init_one(mqrq->sg, mqrq->bounce_buf, buflen);
+
+ return 1;
+}
+
+/*
+ * If writing, bounce the data to the buffer before the request
+ * is sent to the host driver
+ */
+void mmc_queue_bounce_pre(struct mmc_queue_req *mqrq)
+{
+ if (!mqrq->bounce_buf)
+ return;
+
+ if (rq_data_dir(mqrq->req) != WRITE)
+ return;
+
+ sg_copy_to_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
+ mqrq->bounce_buf, mqrq->sg[0].length);
+}
+
+/*
+ * If reading, bounce the data from the buffer after the request
+ * has been handled by the host driver
+ */
+void mmc_queue_bounce_post(struct mmc_queue_req *mqrq)
+{
+ if (!mqrq->bounce_buf)
+ return;
+
+ if (rq_data_dir(mqrq->req) != READ)
+ return;
+
+ sg_copy_from_buffer(mqrq->bounce_sg, mqrq->bounce_sg_len,
+ mqrq->bounce_buf, mqrq->sg[0].length);
+}
Code Review / kvmfornfv.git / blobdiff