On Wed, Sep 23, 2015 at 2:42 PM, Ulf Hansson <ulf.hans...@linaro.org> wrote: > On 22 September 2015 at 11:27, Jon Hunter <jonath...@nvidia.com> wrote: >> 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 <sh...@nvidia.com>. >> >> Signed-off-by: Seshagiri Holi <sh...@nvidia.com> >> Signed-off-by: Jon Hunter <jonath...@nvidia.com> > > Thanks, applied for next!
Awesome! Thanks Ulf! (and Jon for preparing the patches) I'll prepare a patch to implement Gwendal's previous suggestion based on this 3.18 patch: https://chromium-review.googlesource.com/#/c/299956/ cheers, grant > > Kind regards > Uffe > >> --- >> V4 changes: >> - Moved duplicated test in mmc_blk_ioc_cmd() and mmc_blk_ioc_multi_cmd() >> to mmc_blk_ioctl(). Changed author. >> V3 changes: >> - Updated mmc_ioc_multi_cmd structure per Grant's preference >> V2 changes: >> - Updated changelog and patch per Arnd's feedback >> - Moved mmc_put/get_card() outside of __mmc_blk_ioctl_cmd() >> >> 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 c742cfd7674e..f6acf0f6c410 100644 >> --- a/drivers/mmc/card/block.c >> +++ b/drivers/mmc/card/block.c >> @@ -387,6 +387,24 @@ 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) >> { >> @@ -447,12 +465,9 @@ 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}; >> @@ -461,33 +476,12 @@ 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; >> @@ -530,23 +524,21 @@ 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) >> && >> @@ -557,7 +549,7 @@ 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); >> @@ -565,14 +557,12 @@ 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; >> } >> >> /* >> @@ -582,18 +572,7 @@ 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) { >> /* >> @@ -607,9 +586,42 @@ 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: >> @@ -618,13 +630,97 @@ 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 1f5e68923929..7e385b83b9d8 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 */ >> -- >> 2.1.4 >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/