| Message ID | 20240814153558.708365-3-jens.wiklander@linaro.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Replay Protected Memory Block (RPMB) subsystem | expand |
On Wed, 14 Aug 2024 at 17:36, Jens Wiklander <jens.wiklander@linaro.org> wrote: > > Register eMMC RPMB partition with the RPMB subsystem and provide > an implementation for the RPMB access operations abstracting > the actual multi step process. > > Add a callback to extract the needed device information at registration > to avoid accessing the struct mmc_card at a later stage as we're not > holding a reference counter for this struct. > > Taking the needed reference to md->disk in mmc_blk_alloc_rpmb_part() > instead of in mmc_rpmb_chrdev_open(). This is needed by the > route_frames() function pointer in struct rpmb_ops. > > Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> > Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org> > Tested-by: Manuel Traut <manut@mecka.net> > Reviewed-by: Linus Walleij <linus.walleij@linaro.org> First of all, sorry for the long delay! Besides only one comment, see more below, this looks good to me. > --- > drivers/mmc/core/block.c | 242 ++++++++++++++++++++++++++++++++++++++- > 1 file changed, 240 insertions(+), 2 deletions(-) > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > index 2c9963248fcb..cc7318089cf2 100644 > --- a/drivers/mmc/core/block.c > +++ b/drivers/mmc/core/block.c > @@ -33,6 +33,7 @@ > #include <linux/cdev.h> > #include <linux/mutex.h> > #include <linux/scatterlist.h> > +#include <linux/string.h> > #include <linux/string_helpers.h> > #include <linux/delay.h> > #include <linux/capability.h> > @@ -40,6 +41,7 @@ > #include <linux/pm_runtime.h> > #include <linux/idr.h> > #include <linux/debugfs.h> > +#include <linux/rpmb.h> > > #include <linux/mmc/ioctl.h> > #include <linux/mmc/card.h> > @@ -76,6 +78,48 @@ MODULE_ALIAS("mmc:block"); > #define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16) > #define MMC_EXTRACT_VALUE_FROM_ARG(x) ((x & 0x0000FF00) >> 8) > > +/** > + * struct rpmb_frame - rpmb frame as defined by eMMC 5.1 (JESD84-B51) > + * > + * @stuff : stuff bytes > + * @key_mac : The authentication key or the message authentication > + * code (MAC) depending on the request/response type. > + * The MAC will be delivered in the last (or the only) > + * block of data. > + * @data : Data to be written or read by signed access. > + * @nonce : Random number generated by the host for the requests > + * and copied to the response by the RPMB engine. > + * @write_counter: Counter value for the total amount of the successful > + * authenticated data write requests made by the host. > + * @addr : Address of the data to be programmed to or read > + * from the RPMB. Address is the serial number of > + * the accessed block (half sector 256B). > + * @block_count : Number of blocks (half sectors, 256B) requested to be > + * read/programmed. > + * @result : Includes information about the status of the write counter > + * (valid, expired) and result of the access made to the RPMB. > + * @req_resp : Defines the type of request and response to/from the memory. > + * > + * The stuff bytes and big-endian properties are modeled to fit to the spec. > + */ > +struct rpmb_frame { > + u8 stuff[196]; > + u8 key_mac[32]; > + u8 data[256]; > + u8 nonce[16]; > + __be32 write_counter; > + __be16 addr; > + __be16 block_count; > + __be16 result; > + __be16 req_resp; > +} __packed; > + > +#define RPMB_PROGRAM_KEY 0x1 /* Program RPMB Authentication Key */ > +#define RPMB_GET_WRITE_COUNTER 0x2 /* Read RPMB write counter */ > +#define RPMB_WRITE_DATA 0x3 /* Write data to RPMB partition */ > +#define RPMB_READ_DATA 0x4 /* Read data from RPMB partition */ > +#define RPMB_RESULT_READ 0x5 /* Read result request (Internal) */ > + > static DEFINE_MUTEX(block_mutex); > > /* > @@ -155,6 +199,7 @@ static const struct bus_type mmc_rpmb_bus_type = { > * @id: unique device ID number > * @part_index: partition index (0 on first) > * @md: parent MMC block device > + * @rdev: registered RPMB device > * @node: list item, so we can put this device on a list > */ > struct mmc_rpmb_data { > @@ -163,6 +208,7 @@ struct mmc_rpmb_data { > int id; > unsigned int part_index; > struct mmc_blk_data *md; > + struct rpmb_dev *rdev; > struct list_head node; > }; > > @@ -2670,7 +2716,6 @@ static int mmc_rpmb_chrdev_open(struct inode *inode, struct file *filp) > > get_device(&rpmb->dev); > filp->private_data = rpmb; > - mmc_blk_get(rpmb->md->disk); If I understand correctly, the call to mmc_blk_get() is here to reference count the usage of the md->disk. So when a user decides to open the chrdev, we are keeping a reference to the corresponding data around, until the corresponding file descriptor is closed and mmc_rpmb_chrdev_release() is called. We do the similar thing if the regular mmc block device is opened. If we change to increase/decrease the reference count from mmc_blk_alloc_rpmb_part()/mmc_blk_rpmb_device_release() instead - are you certain that we are still taking care of the above scenario correctly? I guess a test that opens the chrdev and then unbinding the mmc host driver should tell us. :-) > > return nonseekable_open(inode, filp); > } > @@ -2680,7 +2725,6 @@ static int mmc_rpmb_chrdev_release(struct inode *inode, struct file *filp) > struct mmc_rpmb_data *rpmb = container_of(inode->i_cdev, > struct mmc_rpmb_data, chrdev); > > - mmc_blk_put(rpmb->md); > put_device(&rpmb->dev); > > return 0; > @@ -2701,10 +2745,165 @@ static void mmc_blk_rpmb_device_release(struct device *dev) > { > struct mmc_rpmb_data *rpmb = dev_get_drvdata(dev); > > + rpmb_dev_unregister(rpmb->rdev); > + mmc_blk_put(rpmb->md); > ida_free(&mmc_rpmb_ida, rpmb->id); > kfree(rpmb); > } > [...] Kind regards Uffe
On Tue, 20 Aug 2024 at 16:47, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > On Wed, 14 Aug 2024 at 17:36, Jens Wiklander <jens.wiklander@linaro.org> wrote: > > > > Register eMMC RPMB partition with the RPMB subsystem and provide > > an implementation for the RPMB access operations abstracting > > the actual multi step process. > > > > Add a callback to extract the needed device information at registration > > to avoid accessing the struct mmc_card at a later stage as we're not > > holding a reference counter for this struct. > > > > Taking the needed reference to md->disk in mmc_blk_alloc_rpmb_part() > > instead of in mmc_rpmb_chrdev_open(). This is needed by the > > route_frames() function pointer in struct rpmb_ops. > > > > Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> > > Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> > > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org> > > Tested-by: Manuel Traut <manut@mecka.net> > > Reviewed-by: Linus Walleij <linus.walleij@linaro.org> > > First of all, sorry for the long delay! Besides only one comment, see > more below, this looks good to me. > > > --- > > drivers/mmc/core/block.c | 242 ++++++++++++++++++++++++++++++++++++++- > > 1 file changed, 240 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > > index 2c9963248fcb..cc7318089cf2 100644 > > --- a/drivers/mmc/core/block.c > > +++ b/drivers/mmc/core/block.c > > @@ -33,6 +33,7 @@ > > #include <linux/cdev.h> > > #include <linux/mutex.h> > > #include <linux/scatterlist.h> > > +#include <linux/string.h> > > #include <linux/string_helpers.h> > > #include <linux/delay.h> > > #include <linux/capability.h> > > @@ -40,6 +41,7 @@ > > #include <linux/pm_runtime.h> > > #include <linux/idr.h> > > #include <linux/debugfs.h> > > +#include <linux/rpmb.h> > > > > #include <linux/mmc/ioctl.h> > > #include <linux/mmc/card.h> > > @@ -76,6 +78,48 @@ MODULE_ALIAS("mmc:block"); > > #define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16) > > #define MMC_EXTRACT_VALUE_FROM_ARG(x) ((x & 0x0000FF00) >> 8) > > > > +/** > > + * struct rpmb_frame - rpmb frame as defined by eMMC 5.1 (JESD84-B51) > > + * > > + * @stuff : stuff bytes > > + * @key_mac : The authentication key or the message authentication > > + * code (MAC) depending on the request/response type. > > + * The MAC will be delivered in the last (or the only) > > + * block of data. > > + * @data : Data to be written or read by signed access. > > + * @nonce : Random number generated by the host for the requests > > + * and copied to the response by the RPMB engine. > > + * @write_counter: Counter value for the total amount of the successful > > + * authenticated data write requests made by the host. > > + * @addr : Address of the data to be programmed to or read > > + * from the RPMB. Address is the serial number of > > + * the accessed block (half sector 256B). > > + * @block_count : Number of blocks (half sectors, 256B) requested to be > > + * read/programmed. > > + * @result : Includes information about the status of the write counter > > + * (valid, expired) and result of the access made to the RPMB. > > + * @req_resp : Defines the type of request and response to/from the memory. > > + * > > + * The stuff bytes and big-endian properties are modeled to fit to the spec. > > + */ > > +struct rpmb_frame { > > + u8 stuff[196]; > > + u8 key_mac[32]; > > + u8 data[256]; > > + u8 nonce[16]; > > + __be32 write_counter; > > + __be16 addr; > > + __be16 block_count; > > + __be16 result; > > + __be16 req_resp; > > +} __packed; > > + > > +#define RPMB_PROGRAM_KEY 0x1 /* Program RPMB Authentication Key */ > > +#define RPMB_GET_WRITE_COUNTER 0x2 /* Read RPMB write counter */ > > +#define RPMB_WRITE_DATA 0x3 /* Write data to RPMB partition */ > > +#define RPMB_READ_DATA 0x4 /* Read data from RPMB partition */ > > +#define RPMB_RESULT_READ 0x5 /* Read result request (Internal) */ > > + > > static DEFINE_MUTEX(block_mutex); > > > > /* > > @@ -155,6 +199,7 @@ static const struct bus_type mmc_rpmb_bus_type = { > > * @id: unique device ID number > > * @part_index: partition index (0 on first) > > * @md: parent MMC block device > > + * @rdev: registered RPMB device > > * @node: list item, so we can put this device on a list > > */ > > struct mmc_rpmb_data { > > @@ -163,6 +208,7 @@ struct mmc_rpmb_data { > > int id; > > unsigned int part_index; > > struct mmc_blk_data *md; > > + struct rpmb_dev *rdev; > > struct list_head node; > > }; > > > > @@ -2670,7 +2716,6 @@ static int mmc_rpmb_chrdev_open(struct inode *inode, struct file *filp) > > > > get_device(&rpmb->dev); > > filp->private_data = rpmb; > > - mmc_blk_get(rpmb->md->disk); > > If I understand correctly, the call to mmc_blk_get() is here to > reference count the usage of the md->disk. So when a user decides to > open the chrdev, we are keeping a reference to the corresponding data > around, until the corresponding file descriptor is closed and > mmc_rpmb_chrdev_release() is called. We do the similar thing if the > regular mmc block device is opened. > > If we change to increase/decrease the reference count from > mmc_blk_alloc_rpmb_part()/mmc_blk_rpmb_device_release() instead - are > you certain that we are still taking care of the above scenario > correctly? > > I guess a test that opens the chrdev and then unbinding the mmc host > driver should tell us. :-) From your nice little debugging session conveyed to me offlist, you have convinced me that this is perfectly okay. Therefore, please add: Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Kind regards Uffe
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 2c9963248fcb..cc7318089cf2 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -33,6 +33,7 @@ #include <linux/cdev.h> #include <linux/mutex.h> #include <linux/scatterlist.h> +#include <linux/string.h> #include <linux/string_helpers.h> #include <linux/delay.h> #include <linux/capability.h> @@ -40,6 +41,7 @@ #include <linux/pm_runtime.h> #include <linux/idr.h> #include <linux/debugfs.h> +#include <linux/rpmb.h> #include <linux/mmc/ioctl.h> #include <linux/mmc/card.h> @@ -76,6 +78,48 @@ MODULE_ALIAS("mmc:block"); #define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16) #define MMC_EXTRACT_VALUE_FROM_ARG(x) ((x & 0x0000FF00) >> 8) +/** + * struct rpmb_frame - rpmb frame as defined by eMMC 5.1 (JESD84-B51) + * + * @stuff : stuff bytes + * @key_mac : The authentication key or the message authentication + * code (MAC) depending on the request/response type. + * The MAC will be delivered in the last (or the only) + * block of data. + * @data : Data to be written or read by signed access. + * @nonce : Random number generated by the host for the requests + * and copied to the response by the RPMB engine. + * @write_counter: Counter value for the total amount of the successful + * authenticated data write requests made by the host. + * @addr : Address of the data to be programmed to or read + * from the RPMB. Address is the serial number of + * the accessed block (half sector 256B). + * @block_count : Number of blocks (half sectors, 256B) requested to be + * read/programmed. + * @result : Includes information about the status of the write counter + * (valid, expired) and result of the access made to the RPMB. + * @req_resp : Defines the type of request and response to/from the memory. + * + * The stuff bytes and big-endian properties are modeled to fit to the spec. + */ +struct rpmb_frame { + u8 stuff[196]; + u8 key_mac[32]; + u8 data[256]; + u8 nonce[16]; + __be32 write_counter; + __be16 addr; + __be16 block_count; + __be16 result; + __be16 req_resp; +} __packed; + +#define RPMB_PROGRAM_KEY 0x1 /* Program RPMB Authentication Key */ +#define RPMB_GET_WRITE_COUNTER 0x2 /* Read RPMB write counter */ +#define RPMB_WRITE_DATA 0x3 /* Write data to RPMB partition */ +#define RPMB_READ_DATA 0x4 /* Read data from RPMB partition */ +#define RPMB_RESULT_READ 0x5 /* Read result request (Internal) */ + static DEFINE_MUTEX(block_mutex); /* @@ -155,6 +199,7 @@ static const struct bus_type mmc_rpmb_bus_type = { * @id: unique device ID number * @part_index: partition index (0 on first) * @md: parent MMC block device + * @rdev: registered RPMB device * @node: list item, so we can put this device on a list */ struct mmc_rpmb_data { @@ -163,6 +208,7 @@ struct mmc_rpmb_data { int id; unsigned int part_index; struct mmc_blk_data *md; + struct rpmb_dev *rdev; struct list_head node; }; @@ -2670,7 +2716,6 @@ static int mmc_rpmb_chrdev_open(struct inode *inode, struct file *filp) get_device(&rpmb->dev); filp->private_data = rpmb; - mmc_blk_get(rpmb->md->disk); return nonseekable_open(inode, filp); } @@ -2680,7 +2725,6 @@ static int mmc_rpmb_chrdev_release(struct inode *inode, struct file *filp) struct mmc_rpmb_data *rpmb = container_of(inode->i_cdev, struct mmc_rpmb_data, chrdev); - mmc_blk_put(rpmb->md); put_device(&rpmb->dev); return 0; @@ -2701,10 +2745,165 @@ static void mmc_blk_rpmb_device_release(struct device *dev) { struct mmc_rpmb_data *rpmb = dev_get_drvdata(dev); + rpmb_dev_unregister(rpmb->rdev); + mmc_blk_put(rpmb->md); ida_free(&mmc_rpmb_ida, rpmb->id); kfree(rpmb); } +static void free_idata(struct mmc_blk_ioc_data **idata, unsigned int cmd_count) +{ + unsigned int n; + + for (n = 0; n < cmd_count; n++) + kfree(idata[n]); + kfree(idata); +} + +static struct mmc_blk_ioc_data **alloc_idata(struct mmc_rpmb_data *rpmb, + unsigned int cmd_count) +{ + struct mmc_blk_ioc_data **idata; + unsigned int n; + + idata = kcalloc(cmd_count, sizeof(*idata), GFP_KERNEL); + if (!idata) + return NULL; + + for (n = 0; n < cmd_count; n++) { + idata[n] = kcalloc(1, sizeof(**idata), GFP_KERNEL); + if (!idata[n]) { + free_idata(idata, n); + return NULL; + } + idata[n]->rpmb = rpmb; + } + + return idata; +} + +static void set_idata(struct mmc_blk_ioc_data *idata, u32 opcode, + int write_flag, u8 *buf, unsigned int buf_bytes) +{ + /* + * The size of an RPMB frame must match what's expected by the + * hardware. + */ + BUILD_BUG_ON(sizeof(struct rpmb_frame) != 512); + + idata->ic.opcode = opcode; + idata->ic.flags = MMC_RSP_R1 | MMC_CMD_ADTC; + idata->ic.write_flag = write_flag; + idata->ic.blksz = sizeof(struct rpmb_frame); + idata->ic.blocks = buf_bytes / idata->ic.blksz; + idata->buf = buf; + idata->buf_bytes = buf_bytes; +} + +static int mmc_route_rpmb_frames(struct device *dev, u8 *req, + unsigned int req_len, u8 *resp, + unsigned int resp_len) +{ + struct rpmb_frame *frm = (struct rpmb_frame *)req; + struct mmc_rpmb_data *rpmb = dev_get_drvdata(dev); + struct mmc_blk_data *md = rpmb->md; + struct mmc_blk_ioc_data **idata; + struct mmc_queue_req *mq_rq; + unsigned int cmd_count; + struct request *rq; + u16 req_type; + bool write; + int ret; + + if (IS_ERR(md->queue.card)) + return PTR_ERR(md->queue.card); + + if (req_len < sizeof(*frm)) + return -EINVAL; + + req_type = be16_to_cpu(frm->req_resp); + switch (req_type) { + case RPMB_PROGRAM_KEY: + if (req_len != sizeof(struct rpmb_frame) || + resp_len != sizeof(struct rpmb_frame)) + return -EINVAL; + write = true; + break; + case RPMB_GET_WRITE_COUNTER: + if (req_len != sizeof(struct rpmb_frame) || + resp_len != sizeof(struct rpmb_frame)) + return -EINVAL; + write = false; + break; + case RPMB_WRITE_DATA: + if (req_len % sizeof(struct rpmb_frame) || + resp_len != sizeof(struct rpmb_frame)) + return -EINVAL; + write = true; + break; + case RPMB_READ_DATA: + if (req_len != sizeof(struct rpmb_frame) || + resp_len % sizeof(struct rpmb_frame)) + return -EINVAL; + write = false; + break; + default: + return -EINVAL; + } + + if (write) + cmd_count = 3; + else + cmd_count = 2; + + idata = alloc_idata(rpmb, cmd_count); + if (!idata) + return -ENOMEM; + + if (write) { + struct rpmb_frame *frm = (struct rpmb_frame *)resp; + + /* Send write request frame(s) */ + set_idata(idata[0], MMC_WRITE_MULTIPLE_BLOCK, + 1 | MMC_CMD23_ARG_REL_WR, req, req_len); + + /* Send result request frame */ + memset(frm, 0, sizeof(*frm)); + frm->req_resp = cpu_to_be16(RPMB_RESULT_READ); + set_idata(idata[1], MMC_WRITE_MULTIPLE_BLOCK, 1, resp, + resp_len); + + /* Read response frame */ + set_idata(idata[2], MMC_READ_MULTIPLE_BLOCK, 0, resp, resp_len); + } else { + /* Send write request frame(s) */ + set_idata(idata[0], MMC_WRITE_MULTIPLE_BLOCK, 1, req, req_len); + + /* Read response frame */ + set_idata(idata[1], MMC_READ_MULTIPLE_BLOCK, 0, resp, resp_len); + } + + rq = blk_mq_alloc_request(md->queue.queue, REQ_OP_DRV_OUT, 0); + if (IS_ERR(rq)) { + ret = PTR_ERR(rq); + goto out; + } + + mq_rq = req_to_mmc_queue_req(rq); + mq_rq->drv_op = MMC_DRV_OP_IOCTL_RPMB; + mq_rq->drv_op_result = -EIO; + mq_rq->drv_op_data = idata; + mq_rq->ioc_count = cmd_count; + blk_execute_rq(rq, false); + ret = req_to_mmc_queue_req(rq)->drv_op_result; + + blk_mq_free_request(rq); + +out: + free_idata(idata, cmd_count); + return ret; +} + static int mmc_blk_alloc_rpmb_part(struct mmc_card *card, struct mmc_blk_data *md, unsigned int part_index, @@ -2739,6 +2938,7 @@ static int mmc_blk_alloc_rpmb_part(struct mmc_card *card, rpmb->dev.release = mmc_blk_rpmb_device_release; device_initialize(&rpmb->dev); dev_set_drvdata(&rpmb->dev, rpmb); + mmc_blk_get(md->disk); rpmb->md = md; cdev_init(&rpmb->chrdev, &mmc_rpmb_fileops); @@ -3000,6 +3200,42 @@ static void mmc_blk_remove_debugfs(struct mmc_card *card, #endif /* CONFIG_DEBUG_FS */ +static void mmc_blk_rpmb_add(struct mmc_card *card) +{ + struct mmc_blk_data *md = dev_get_drvdata(&card->dev); + struct mmc_rpmb_data *rpmb; + struct rpmb_dev *rdev; + unsigned int n; + u32 cid[4]; + struct rpmb_descr descr = { + .type = RPMB_TYPE_EMMC, + .route_frames = mmc_route_rpmb_frames, + .reliable_wr_count = card->ext_csd.enhanced_rpmb_supported ? + 2 : 32, + .capacity = card->ext_csd.raw_rpmb_size_mult, + .dev_id = (void *)cid, + .dev_id_len = sizeof(cid), + }; + + /* + * Provice CID as an octet array. The CID needs to be interpreted + * when used as input to derive the RPMB key since some fields + * will change due to firmware updates. + */ + for (n = 0; n < 4; n++) + cid[n] = be32_to_cpu((__force __be32)card->raw_cid[n]); + + list_for_each_entry(rpmb, &md->rpmbs, node) { + rdev = rpmb_dev_register(&rpmb->dev, &descr); + if (IS_ERR(rdev)) { + pr_warn("%s: could not register RPMB device\n", + dev_name(&rpmb->dev)); + continue; + } + rpmb->rdev = rdev; + } +} + static int mmc_blk_probe(struct mmc_card *card) { struct mmc_blk_data *md; @@ -3045,6 +3281,8 @@ static int mmc_blk_probe(struct mmc_card *card) pm_runtime_enable(&card->dev); } + mmc_blk_rpmb_add(card); + return 0; out: