diff options
author | John Calixto <john.calixto@modsystems.com> | 2011-04-27 02:56:29 +0400 |
---|---|---|
committer | Chris Ball <cjb@laptop.org> | 2011-05-25 05:02:54 +0400 |
commit | cb87ea28ed9e75a41eb456bfcb547b4e6f10e750 (patch) | |
tree | e3fe4a653bd96815c650dd9f5db11edc6b39b0db /include/linux/mmc | |
parent | 641c3187b9d53cfd4c23b0ce2ab18a13d5e775e5 (diff) | |
download | linux-cb87ea28ed9e75a41eb456bfcb547b4e6f10e750.tar.xz |
mmc: core: Add mmc CMD+ACMD passthrough ioctl
Allows appropriately-privileged applications to send CMD (normal) and ACMD
(application-specific; preceded with CMD55) commands to cards/devices on
the mmc bus. This is primarily useful for enabling the security
functionality built in to every SD card.
It can also be used as a generic passthrough (e.g. to enable virtual
machines to control mmc bus devices directly). However, this use case has
not been tested rigorously. Generic passthrough testing was only conducted
for a few non-security opcodes to prove the feasibility of the passthrough.
Since any opcode can be sent using this passthrough, it is very possible to
render the card/device unusable. Applications that use this ioctl must
have CAP_SYS_RAWIO.
Security commands tested on TI PCIxx12 (SDHCI), Sigma Designs SMP8652 SoC,
TI OMAP3621/OMAP3630 SoC, Samsung S5PC110 SoC, Qualcomm MSM7200A SoC.
Signed-off-by: John Calixto <john.calixto@modsystems.com>
Reviewed-by: Andrei Warkentin <andreiw@motorola.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'include/linux/mmc')
-rw-r--r-- | include/linux/mmc/Kbuild | 1 | ||||
-rw-r--r-- | include/linux/mmc/core.h | 1 | ||||
-rw-r--r-- | include/linux/mmc/ioctl.h | 54 |
3 files changed, 56 insertions, 0 deletions
diff --git a/include/linux/mmc/Kbuild b/include/linux/mmc/Kbuild new file mode 100644 index 000000000000..1fb26448faa9 --- /dev/null +++ b/include/linux/mmc/Kbuild @@ -0,0 +1 @@ +header-y += ioctl.h diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index f8e4bcbd2846..cbe8d55f64c4 100644 --- a/include/linux/mmc/core.h +++ b/include/linux/mmc/core.h @@ -133,6 +133,7 @@ struct mmc_card; extern void mmc_wait_for_req(struct mmc_host *, struct mmc_request *); extern int mmc_wait_for_cmd(struct mmc_host *, struct mmc_command *, int); +extern int mmc_app_cmd(struct mmc_host *, struct mmc_card *); extern int mmc_wait_for_app_cmd(struct mmc_host *, struct mmc_card *, struct mmc_command *, int); extern int mmc_switch(struct mmc_card *, u8, u8, u8, unsigned int); diff --git a/include/linux/mmc/ioctl.h b/include/linux/mmc/ioctl.h new file mode 100644 index 000000000000..5baf2983a12f --- /dev/null +++ b/include/linux/mmc/ioctl.h @@ -0,0 +1,54 @@ +#ifndef LINUX_MMC_IOCTL_H +#define LINUX_MMC_IOCTL_H +struct mmc_ioc_cmd { + /* Implies direction of data. true = write, false = read */ + int write_flag; + + /* Application-specific command. true = precede with CMD55 */ + int is_acmd; + + __u32 opcode; + __u32 arg; + __u32 response[4]; /* CMD response */ + unsigned int flags; + unsigned int blksz; + unsigned int blocks; + + /* + * Sleep at least postsleep_min_us useconds, and at most + * postsleep_max_us useconds *after* issuing command. Needed for + * some read commands for which cards have no other way of indicating + * they're ready for the next command (i.e. there is no equivalent of + * a "busy" indicator for read operations). + */ + unsigned int postsleep_min_us; + unsigned int postsleep_max_us; + + /* + * Override driver-computed timeouts. Note the difference in units! + */ + unsigned int data_timeout_ns; + unsigned int cmd_timeout_ms; + + /* + * For 64-bit machines, the next member, ``__u64 data_ptr``, wants to + * be 8-byte aligned. Make sure this struct is the same size when + * built for 32-bit. + */ + __u32 __pad; + + /* DAT buffer */ + __u64 data_ptr; +}; +#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) + +/* + * 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 + * is enforced per ioctl call. For larger data transfers, use the normal + * block device operations. + */ +#define MMC_IOC_MAX_BYTES (512L * 256) +#endif /* LINUX_MMC_IOCTL_H */ |