[linux-yocto] [PATCH 1/4] mmc: block: Add new ioctl to send multi commands
Lim Key Seong
key.seong.lim at intel.com
Thu Jun 16 22:58:40 PDT 2016
From: Jon Hunter <jonathanh at nvidia.com>
Certain eMMC devices allow vendor specific device information to be read
via a sequence of vendor commands. These vendor commands must be issued
in sequence and an atomic fashion. One way to support this would be to
add an ioctl function for sending a sequence of commands to the device
atomically as proposed here. These multi commands are simple array of
the existing mmc_ioc_cmd structure.
The structure passed via the ioctl uses a __u64 type to specify the number
of commands (so that the structure is aligned on a 64-bit boundary) and a
zero length array as a header for list of commands to be issued. The
maximum number of commands that can be sent is determined by
MMC_IOC_MAX_CMDS (which defaults to 255 and should be more than
sufficient).
This based upon work by Seshagiri Holi <sholi at nvidia.com>.
Signed-off-by: Seshagiri Holi <sholi at nvidia.com>
Signed-off-by: Jon Hunter <jonathanh at nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
(cherry picked from commit a5f5774c55a2e3ed75f4d6c5556b7bfcb726e6f0)
Signed-off-by: Lim Key Seong <key.seong.lim at intel.com>
---
drivers/mmc/card/block.c | 206 ++++++++++++++++++++++++++++++-----------
include/uapi/linux/mmc/ioctl.h | 19 +++-
2 files changed, 169 insertions(+), 56 deletions(-)
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 1ea0c8a..5e9ce55 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -384,6 +384,24 @@ out:
return ERR_PTR(err);
}
+static int mmc_blk_ioctl_copy_to_user(struct mmc_ioc_cmd __user *ic_ptr,
+ struct mmc_blk_ioc_data *idata)
+{
+ struct mmc_ioc_cmd *ic = &idata->ic;
+
+ if (copy_to_user(&(ic_ptr->response), ic->response,
+ sizeof(ic->response)))
+ return -EFAULT;
+
+ if (!idata->ic.write_flag) {
+ if (copy_to_user((void __user *)(unsigned long)ic->data_ptr,
+ idata->buf, idata->buf_bytes))
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
static int ioctl_rpmb_card_status_poll(struct mmc_card *card, u32 *status,
u32 retries_max)
{
@@ -444,12 +462,9 @@ out:
return err;
}
-static int mmc_blk_ioctl_cmd(struct block_device *bdev,
- struct mmc_ioc_cmd __user *ic_ptr)
+static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md,
+ struct mmc_blk_ioc_data *idata)
{
- struct mmc_blk_ioc_data *idata;
- struct mmc_blk_data *md;
- struct mmc_card *card;
struct mmc_command cmd = {0};
struct mmc_data data = {0};
struct mmc_request mrq = {NULL};
@@ -458,33 +473,12 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
int is_rpmb = false;
u32 status = 0;
- /*
- * The caller must have CAP_SYS_RAWIO, and must be calling this on the
- * whole block device, not on a partition. This prevents overspray
- * between sibling partitions.
- */
- if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
- return -EPERM;
-
- idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
- if (IS_ERR(idata))
- return PTR_ERR(idata);
-
- md = mmc_blk_get(bdev->bd_disk);
- if (!md) {
- err = -EINVAL;
- goto cmd_err;
- }
+ if (!card || !md || !idata)
+ return -EINVAL;
if (md->area_type & MMC_BLK_DATA_AREA_RPMB)
is_rpmb = true;
- card = md->queue.card;
- if (IS_ERR(card)) {
- err = PTR_ERR(card);
- goto cmd_done;
- }
-
cmd.opcode = idata->ic.opcode;
cmd.arg = idata->ic.arg;
cmd.flags = idata->ic.flags;
@@ -527,23 +521,21 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
mrq.cmd = &cmd;
- mmc_get_card(card);
-
err = mmc_blk_part_switch(card, md);
if (err)
- goto cmd_rel_host;
+ return err;
if (idata->ic.is_acmd) {
err = mmc_app_cmd(card->host, card);
if (err)
- goto cmd_rel_host;
+ return err;
}
if (is_rpmb) {
err = mmc_set_blockcount(card, data.blocks,
idata->ic.write_flag & (1 << 31));
if (err)
- goto cmd_rel_host;
+ return err;
}
if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) &&
@@ -554,7 +546,7 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
pr_err("%s: ioctl_do_sanitize() failed. err = %d",
__func__, err);
- goto cmd_rel_host;
+ return err;
}
mmc_wait_for_req(card->host, &mrq);
@@ -562,14 +554,12 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
if (cmd.error) {
dev_err(mmc_dev(card->host), "%s: cmd error %d\n",
__func__, cmd.error);
- err = cmd.error;
- goto cmd_rel_host;
+ return cmd.error;
}
if (data.error) {
dev_err(mmc_dev(card->host), "%s: data error %d\n",
__func__, data.error);
- err = data.error;
- goto cmd_rel_host;
+ return data.error;
}
/*
@@ -579,18 +569,7 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
if (idata->ic.postsleep_min_us)
usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us);
- if (copy_to_user(&(ic_ptr->response), cmd.resp, sizeof(cmd.resp))) {
- err = -EFAULT;
- goto cmd_rel_host;
- }
-
- if (!idata->ic.write_flag) {
- if (copy_to_user((void __user *)(unsigned long) idata->ic.data_ptr,
- idata->buf, idata->buf_bytes)) {
- err = -EFAULT;
- goto cmd_rel_host;
- }
- }
+ memcpy(&(idata->ic.response), cmd.resp, sizeof(cmd.resp));
if (is_rpmb) {
/*
@@ -604,9 +583,42 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
__func__, status, err);
}
-cmd_rel_host:
+ return err;
+}
+
+static int mmc_blk_ioctl_cmd(struct block_device *bdev,
+ struct mmc_ioc_cmd __user *ic_ptr)
+{
+ struct mmc_blk_ioc_data *idata;
+ struct mmc_blk_data *md;
+ struct mmc_card *card;
+ int err;
+
+ idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
+ if (IS_ERR(idata))
+ return PTR_ERR(idata);
+
+ md = mmc_blk_get(bdev->bd_disk);
+ if (!md) {
+ err = -EINVAL;
+ goto cmd_err;
+ }
+
+ card = md->queue.card;
+ if (IS_ERR(card)) {
+ err = PTR_ERR(card);
+ goto cmd_done;
+ }
+
+ mmc_get_card(card);
+
+ err = __mmc_blk_ioctl_cmd(card, md, idata);
+
mmc_put_card(card);
+ if (!err)
+ err = mmc_blk_ioctl_copy_to_user(ic_ptr, idata);
+
cmd_done:
mmc_blk_put(md);
cmd_err:
@@ -615,13 +627,97 @@ cmd_err:
return err;
}
+static int mmc_blk_ioctl_multi_cmd(struct block_device *bdev,
+ struct mmc_ioc_multi_cmd __user *user)
+{
+ struct mmc_blk_ioc_data **idata = NULL;
+ struct mmc_ioc_cmd __user *cmds = user->cmds;
+ struct mmc_card *card;
+ struct mmc_blk_data *md;
+ int i, err = -EFAULT;
+ __u64 num_of_cmds;
+
+ if (copy_from_user(&num_of_cmds, &user->num_of_cmds,
+ sizeof(num_of_cmds)))
+ return -EFAULT;
+
+ if (num_of_cmds > MMC_IOC_MAX_CMDS)
+ return -EINVAL;
+
+ idata = kcalloc(num_of_cmds, sizeof(*idata), GFP_KERNEL);
+ if (!idata)
+ return -ENOMEM;
+
+ for (i = 0; i < num_of_cmds; i++) {
+ idata[i] = mmc_blk_ioctl_copy_from_user(&cmds[i]);
+ if (IS_ERR(idata[i])) {
+ err = PTR_ERR(idata[i]);
+ num_of_cmds = i;
+ goto cmd_err;
+ }
+ }
+
+ md = mmc_blk_get(bdev->bd_disk);
+ if (!md)
+ goto cmd_err;
+
+ card = md->queue.card;
+ if (IS_ERR(card)) {
+ err = PTR_ERR(card);
+ goto cmd_done;
+ }
+
+ mmc_get_card(card);
+
+ for (i = 0; i < num_of_cmds; i++) {
+ err = __mmc_blk_ioctl_cmd(card, md, idata[i]);
+ if (err) {
+ mmc_put_card(card);
+ goto cmd_done;
+ }
+ }
+
+ mmc_put_card(card);
+
+ /* copy to user if data and response */
+ for (i = 0; i < num_of_cmds; i++) {
+ err = mmc_blk_ioctl_copy_to_user(&cmds[i], idata[i]);
+ if (err)
+ break;
+ }
+
+cmd_done:
+ mmc_blk_put(md);
+cmd_err:
+ for (i = 0; i < num_of_cmds; i++) {
+ kfree(idata[i]->buf);
+ kfree(idata[i]);
+ }
+ kfree(idata);
+ return err;
+}
+
static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
- int ret = -EINVAL;
- if (cmd == MMC_IOC_CMD)
- ret = mmc_blk_ioctl_cmd(bdev, (struct mmc_ioc_cmd __user *)arg);
- return ret;
+ /*
+ * The caller must have CAP_SYS_RAWIO, and must be calling this on the
+ * whole block device, not on a partition. This prevents overspray
+ * between sibling partitions.
+ */
+ if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
+ return -EPERM;
+
+ switch (cmd) {
+ case MMC_IOC_CMD:
+ return mmc_blk_ioctl_cmd(bdev,
+ (struct mmc_ioc_cmd __user *)arg);
+ case MMC_IOC_MULTI_CMD:
+ return mmc_blk_ioctl_multi_cmd(bdev,
+ (struct mmc_ioc_multi_cmd __user *)arg);
+ default:
+ return -EINVAL;
+ }
}
#ifdef CONFIG_COMPAT
diff --git a/include/uapi/linux/mmc/ioctl.h b/include/uapi/linux/mmc/ioctl.h
index 1f5e689..7e385b8 100644
--- a/include/uapi/linux/mmc/ioctl.h
+++ b/include/uapi/linux/mmc/ioctl.h
@@ -45,8 +45,24 @@ struct mmc_ioc_cmd {
};
#define mmc_ioc_cmd_set_data(ic, ptr) ic.data_ptr = (__u64)(unsigned long) ptr
-#define MMC_IOC_CMD _IOWR(MMC_BLOCK_MAJOR, 0, struct mmc_ioc_cmd)
+/**
+ * struct mmc_ioc_multi_cmd - multi command information
+ * @num_of_cmds: Number of commands to send. Must be equal to or less than
+ * MMC_IOC_MAX_CMDS.
+ * @cmds: Array of commands with length equal to 'num_of_cmds'
+ */
+struct mmc_ioc_multi_cmd {
+ __u64 num_of_cmds;
+ struct mmc_ioc_cmd cmds[0];
+};
+#define MMC_IOC_CMD _IOWR(MMC_BLOCK_MAJOR, 0, struct mmc_ioc_cmd)
+/*
+ * MMC_IOC_MULTI_CMD: Used to send an array of MMC commands described by
+ * the structure mmc_ioc_multi_cmd. The MMC driver will issue all
+ * commands in array in sequence to card.
+ */
+#define MMC_IOC_MULTI_CMD _IOWR(MMC_BLOCK_MAJOR, 1, struct mmc_ioc_multi_cmd)
/*
* Since this ioctl is only meant to enhance (and not replace) normal access
* to the mmc bus device, an upper data transfer limit of MMC_IOC_MAX_BYTES
@@ -54,4 +70,5 @@ struct mmc_ioc_cmd {
* block device operations.
*/
#define MMC_IOC_MAX_BYTES (512L * 256)
+#define MMC_IOC_MAX_CMDS 255
#endif /* LINUX_MMC_IOCTL_H */
--
1.9.1
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