Quirks are card-specific workarounds. Usually they involve
tuning mmcblk parameters at mmc_blk_probe time, but can
involve affecting the way mmcblk I/O requests are handled.
The later is necessary to handle Sandisk out-of-spec discard support,
and the small-writes reliability workaround for Toshiba.
Change-Id: Ia5e56d7a2803daba4b9085f2ca12afeadc7d9095
Signed-off-by: Andrei Warkentin <andreiw@xxxxxxxxxxxx>
---
drivers/mmc/card/Kconfig | 7 +++
drivers/mmc/card/Makefile | 1 +
drivers/mmc/card/blk.h | 58 ++++++++++++++++++++
drivers/mmc/card/block-quirks.c | 111 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/card/block.c | 30 ++++++-----
5 files changed, 194 insertions(+), 13 deletions(-)
create mode 100644 drivers/mmc/card/blk.h
create mode 100644 drivers/mmc/card/block-quirks.c
diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
index 86948f9..063fa16 100644
--- a/drivers/mmc/card/Kconfig
+++ b/drivers/mmc/card/Kconfig
@@ -14,6 +14,13 @@ config MMC_BLOCK
mount the filesystem. Almost everyone wishing MMC support
should say Y or M here.
+config MMC_BLOCK_QUIRKS
+ tristate "MMC block device quirks"
+ depends on MMC_BLOCK
+ default y
+ help
+ Say Y here to enable various workarounds for known cards.
+
config MMC_BLOCK_BOUNCE
bool "Use bounce buffer for simple hosts"
depends on MMC_BLOCK
diff --git a/drivers/mmc/card/Makefile b/drivers/mmc/card/Makefile
index 0d40751..fcd3f45 100644
--- a/drivers/mmc/card/Makefile
+++ b/drivers/mmc/card/Makefile
@@ -7,6 +7,7 @@ ifeq ($(CONFIG_MMC_DEBUG),y)
endif
obj-$(CONFIG_MMC_BLOCK) += mmc_block.o
+obj-$(CONFIG_MMC_BLOCK_QUIRKS) += block-quirks.o
mmc_block-objs := block.o queue.o
obj-$(CONFIG_MMC_TEST) += mmc_test.o
diff --git a/drivers/mmc/card/blk.h b/drivers/mmc/card/blk.h
new file mode 100644
index 0000000..a45a37f
--- /dev/null
+++ b/drivers/mmc/card/blk.h
@@ -0,0 +1,58 @@
+#ifndef MMC_BLK_H
+#define MMC_BLK_H
+
+struct gendisk;
+
+#ifdef CONFIG_MMC_BLOCK_QUIRKS
+struct mmc_blk_data;
+
+#define mmc_blk_qrev(hwrev, fwrev, year, month) \
+ (((u64) hwrev) << 40 | \
+ ((u64) fwrev) << 32 | \
+ ((u64) year) << 16 | \
+ ((u64) month))
+
+#define mmc_blk_qrev_card(card) \
+ mmc_blk_qrev(card->cid.hwrev, \
+ card->cid.fwrev, \
+ card->cid.year, \
+ card->cid.month)
+
+struct mmc_blk_quirk {
+ struct rb_node rb_node;
+ const char *name;
+
+ /* First valid revision */
+ u64 rev_start;
+
+ /* Last valid revision */
+ u64 rev_end;
+
+ unsigned int manfid;
+ unsigned short oemid;
+ int (*probe)(struct mmc_blk_data *, struct mmc_card *);
+ int (*adjust)(struct mmc_queue *, struct request *, struct mmc_request *);
+};
+
+
+struct mmc_blk_quirk *mmc_blk_quirk_find(struct mmc_card *card);
+int mmc_blk_quirk_register(struct mmc_blk_quirk *quirk, bool is_mmc);
+#endif /* CONFIG_MMC_BLOCK_QUIRKS */
+
+/*
+ * There is one mmc_blk_data per slot.
+ */
+struct mmc_blk_data {
+ spinlock_t lock;
+ struct gendisk *disk;
+ struct mmc_queue queue;
+
+ unsigned int usage;
+ unsigned int read_only;
+ unsigned int write_align_size;
+#ifdef CONFIG_MMC_BLOCK_QUIRKS
+ struct mmc_blk_quirk *quirk;
+#endif /* CONFIG_MMC_BLOCK_QUIRKS */
+};
+
+#endif
diff --git a/drivers/mmc/card/block-quirks.c b/drivers/mmc/card/block-quirks.c
new file mode 100644
index 0000000..ceae70c
--- /dev/null
+++ b/drivers/mmc/card/block-quirks.c
@@ -0,0 +1,111 @@
+/*
+ * linux/drivers/mmc/card/block-quirks.c
+ *
+ * Copyright (C) 2010 Andrei Warkentin <andreiw@xxxxxxxxxxxx>
+ *
+ * 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/kernel.h>
+#include <linux/semaphore.h>
+#include <linux/mmc/card.h>
+
+#include "queue.h"
+#include "blk.h"
+
+/*
+ Since the goal is to support quirks in removable media, ideally
+ such quirks would be always built into a kernel, hence we need
+ a smarter way to search.
+*/
+static struct rb_root quirk_tree[2] = { RB_ROOT, RB_ROOT };
+
+static int mmc_blk_quirk_cmp(const struct mmc_blk_quirk *quirk,
+ const struct mmc_blk_quirk *cquirk)
+{
+ int ret;
+
+ if (quirk->manfid > cquirk->manfid)
+ return 1;
+ else if (quirk->manfid < cquirk->manfid)
+ return -1;
+
+ if (quirk->oemid > cquirk->oemid)
+ return 1;
+ else if (quirk->oemid < cquirk->oemid)
+ return -1;
+
+ ret = strcmp(quirk->name, cquirk->name);
+ if (!ret)
+ return ret;
+
+ if (quirk->rev_start > cquirk->rev_end)
+ return 1;
+ else if (quirk->rev_end < cquirk->rev_start)
+ return -1;
+
+ /* Overlap in revs or equal. */
+ return 0;
+}
+
+static int mmc_blk_quirk_cmpc(const struct mmc_blk_quirk *quirk,
+ const struct mmc_card *card)
+{
+ struct mmc_blk_quirk cquirk;
+ cquirk.name = card->cid.prod_name;
+ cquirk.rev_start = mmc_blk_qrev_card(card);
+ cquirk.rev_end = cquirk.rev_start;
+ cquirk.manfid = card->cid.manfid;
+ cquirk.oemid = card->cid.oemid;
+ return mmc_blk_quirk_cmp(quirk, &cquirk);
+}
+
+struct mmc_blk_quirk *mmc_blk_quirk_find(struct mmc_card *card)
+{
+ int ret;
+ struct mmc_blk_quirk *quirk;
+ struct rb_node *node = quirk_tree[!mmc_card_mmc(card)].rb_node;
+
+ while (node) {
+ quirk = container_of(node, struct mmc_blk_quirk, rb_node);
+ ret = mmc_blk_quirk_cmpc(quirk, card);
+
+ if (ret < 0)
+ node = node->rb_left;
+ else if (ret > 0)
+ node = node->rb_right;
+ else
+ return quirk;
+ }
+
+ return NULL;
+}
+
+int mmc_blk_quirk_register(struct mmc_blk_quirk *quirk, bool is_mmc)
+{
+ int ret;
+ struct mmc_blk_quirk *cq;
+ struct rb_node **new = &(quirk_tree[!is_mmc].rb_node), *parent = NULL;
+
+ while (*new) {
+ cq = container_of(*new, struct mmc_blk_quirk, rb_node);
+
+ ret = mmc_blk_quirk_cmp(quirk, cq);
+
+ parent = *new;
+ if (ret < 0)
+ new = &(parent->rb_left);
+ else if(ret > 0)
+ new = &(parent->rb_right);
+ else
+ /* Overlap */
+ return -EINVAL;
+
+ }
+
+ rb_link_node(&quirk->rb_node, parent, new);
+ rb_insert_color(&quirk->rb_node, &quirk_tree[!is_mmc]);
+ return 0;
+}
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 498c439..8b72407 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -42,6 +42,7 @@
#include <asm/uaccess.h>
#include "queue.h"
+#include "blk.h"
MODULE_ALIAS("mmc:block");
@@ -53,19 +54,6 @@ MODULE_ALIAS("mmc:block");
static DECLARE_BITMAP(dev_use, MMC_NUM_MINORS);
-/*
- * There is one mmc_blk_data per slot.
- */
-struct mmc_blk_data {
- spinlock_t lock;
- struct gendisk *disk;
- struct mmc_queue queue;
-
- unsigned int usage;
- unsigned int read_only;
- unsigned int write_align_size;
-};
-
static DEFINE_MUTEX(open_lock);
static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
@@ -421,6 +409,11 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
brq.data.sg = mq->sg;
brq.data.sg_len = mmc_queue_map_sg(mq);
+#ifdef CONFIG_MMC_BLOCK_QUIRKS
+ if (md->quirk && md->quirk->adjust)
+ md->quirk->adjust(mq, req, &brq.mrq);
+#endif /* CONFIG_MMC_BLOCK_QUIRKS */
+
/*
* Adjust the sg list so it is the same size as the
* request.
@@ -727,6 +720,9 @@ mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
static int mmc_blk_probe(struct mmc_card *card)
{
struct mmc_blk_data *md;
+#ifdef CONFIG_MMC_BLOCK_QUIRKS
+ struct mmc_blk_quirk *quirk;
+#endif /* CONFIG_MMC_BLOCK_QUIRKS */
int err;
char cap_str[10];
@@ -745,6 +741,14 @@ static int mmc_blk_probe(struct mmc_card *card)
if (err)
goto out;
+#ifdef CONFIG_MMC_BLOCK_QUIRKS
+ md->quirk = mmc_blk_quirk_find(card);
+ if (md->quirk && md->quirk->probe)
+ err = quirk->probe(md, card);
+ if (err)
+ goto out;
+#endif /* CONFIG_MMC_BLOCK_QUIRKS */
+
string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2,
cap_str, sizeof(cap_str));
printk(KERN_INFO "%s: %s %s %s %s\n",
--
1.7.0.4
--
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