ums: support multiple LUNs at once

Extend the ums command to accept a list of block devices. Each of these
will be exported as a separate LUN. An example use-case would be:

ums 0 mmc 0,0.1,0.2

... which would export LUNs for eMMC 0's user data, boot0, and boot1 HW
partitions. This is useful since it allows the host access to everything
on the eMMC without having to somehow stop the ums command from executing
and restart it with different parameters.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

common/cmd_usb_mass_storage.c

@@ -2,6 +2,8 @@
  * Copyright (C) 2011 Samsung Electronics
  * Lukasz Majewski <l.majewski@samsung.com>
  *
+ * Copyright (c) 2015, NVIDIA CORPORATION. All rights reserved.
+ *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
@@ -17,7 +19,7 @@
 static int ums_read_sector(struct ums *ums_dev,
 			   ulong start, lbaint_t blkcnt, void *buf)
 {
-	block_dev_desc_t *block_dev = ums_dev->block_dev;
+	block_dev_desc_t *block_dev = &ums_dev->block_dev;
 	lbaint_t blkstart = start + ums_dev->start_sector;
 
 	return block_dev->block_read(block_dev, blkstart, blkcnt, buf);
@@ -26,39 +28,98 @@ static int ums_read_sector(struct ums *ums_dev,
 static int ums_write_sector(struct ums *ums_dev,
 			    ulong start, lbaint_t blkcnt, const void *buf)
 {
-	block_dev_desc_t *block_dev = ums_dev->block_dev;
+	block_dev_desc_t *block_dev = &ums_dev->block_dev;
 	lbaint_t blkstart = start + ums_dev->start_sector;
 
 	return block_dev->block_write(block_dev, blkstart, blkcnt, buf);
 }
 
-static struct ums ums_dev = {
+static struct ums *ums;
-	.read_sector = ums_read_sector,
+static int ums_count;
-	.write_sector = ums_write_sector,
+
-	.name = "UMS disk",
+static void ums_fini(void)
-};
+{
+	int i;
+
+	for (i = 0; i < ums_count; i++)
+		free((void *)ums[i].name);
+	free(ums);
+	ums = 0;
+	ums_count = 0;
+}
+
+#define UMS_NAME_LEN 16
 
-struct ums *ums_init(const char *devtype, const char *devnum)
+static int ums_init(const char *devtype, const char *devnums)
 {
+	char *s, *t, *devnum, *name;
 	block_dev_desc_t *block_dev;
 	int ret;
+	struct ums *ums_new;
 
-	ret = get_device(devtype, devnum, &block_dev);
+	s = strdup(devnums);
-	if (ret < 0)
+	if (!s)
-		return NULL;
+		return -1;
+
+	t = s;
+	ums_count = 0;
+
+	for (;;) {
+		devnum = strsep(&t, ",");
+		if (!devnum)
+			break;
+
+		ret = get_device(devtype, devnum, &block_dev);
+		if (ret < 0)
+			goto cleanup;
+
+		/* f_mass_storage.c assumes SECTOR_SIZE sectors */
+		if (block_dev->blksz != SECTOR_SIZE) {
+			ret = -1;
+			goto cleanup;
+		}
 
-	/* f_mass_storage.c assumes SECTOR_SIZE sectors */
+		ums_new = realloc(ums, (ums_count + 1) * sizeof(*ums));
-	if (block_dev->blksz != SECTOR_SIZE)
+		if (!ums_new) {
-		return NULL;
+			ret = -1;
+			goto cleanup;
+		}
+		ums = ums_new;
+
+		ums[ums_count].read_sector = ums_read_sector;
+		ums[ums_count].write_sector = ums_write_sector;
+		ums[ums_count].start_sector = 0;
+		ums[ums_count].num_sectors = block_dev->lba;
+		name = malloc(UMS_NAME_LEN);
+		if (!name) {
+			ret = -1;
+			goto cleanup;
+		}
+		snprintf(name, UMS_NAME_LEN, "UMS disk %d", ums_count);
+		ums[ums_count].name = name;
+		ums[ums_count].block_dev = *block_dev;
+
+		printf("UMS: LUN %d, dev %d, hwpart %d, sector %#x, count %#x\n",
+		       ums_count, ums[ums_count].block_dev.dev,
+		       ums[ums_count].block_dev.hwpart,
+		       ums[ums_count].start_sector,
+		       ums[ums_count].num_sectors);
+
+		ums_count++;
+	}
+
+	if (!ums_count)
+		ret = -1;
+	else
+		ret = 0;
 
-	ums_dev.block_dev = block_dev;
+cleanup:
-	ums_dev.start_sector = 0;
+	free(s);
-	ums_dev.num_sectors = block_dev->lba;
 
-	printf("UMS: disk start sector: %#x, count: %#x\n",
+	if (ret < 0)
-	       ums_dev.start_sector, ums_dev.num_sectors);
+		ums_fini();
 
-	return &ums_dev;
+	return ret;
 }
 
 int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
@@ -67,7 +128,6 @@ int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
 	const char *usb_controller;
 	const char *devtype;
 	const char *devnum;
-	struct ums *ums;
 	unsigned int controller_index;
 	int rc;
 	int cable_ready_timeout __maybe_unused;
@@ -84,27 +144,30 @@ int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
 		devnum  = argv[2];
 	}
 
-	ums = ums_init(devtype, devnum);
+	rc = ums_init(devtype, devnum);
-	if (!ums)
+	if (rc < 0)
 		return CMD_RET_FAILURE;
 
 	controller_index = (unsigned int)(simple_strtoul(
 				usb_controller,	NULL, 0));
 	if (board_usb_init(controller_index, USB_INIT_DEVICE)) {
 		error("Couldn't init USB controller.");
-		return CMD_RET_FAILURE;
+		rc = CMD_RET_FAILURE;
+		goto cleanup_ums_init;
 	}
 
-	rc = fsg_init(ums);
+	rc = fsg_init(ums, ums_count);
 	if (rc) {
 		error("fsg_init failed");
-		return CMD_RET_FAILURE;
+		rc = CMD_RET_FAILURE;
+		goto cleanup_board;
 	}
 
 	rc = g_dnl_register("usb_dnl_ums");
 	if (rc) {
 		error("g_dnl_register failed");
-		return CMD_RET_FAILURE;
+		rc = CMD_RET_FAILURE;
+		goto cleanup_board;
 	}
 
 	/* Timeout unit: seconds */
@@ -120,12 +183,14 @@ int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
 		while (!g_dnl_board_usb_cable_connected()) {
 			if (ctrlc()) {
 				puts("\rCTRL+C - Operation aborted.\n");
-				goto exit;
+				rc = CMD_RET_SUCCESS;
+				goto cleanup_register;
 			}
 			if (!cable_ready_timeout) {
 				puts("\rUSB cable not detected.\n" \
 				     "Command exit.\n");
-				goto exit;
+				rc = CMD_RET_SUCCESS;
+				goto cleanup_register;
 			}
 
 			printf("\rAuto exit in: %.2d s.", cable_ready_timeout);
@@ -148,13 +213,19 @@ int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
 			if (rc == -EPIPE)
 				printf("\rCTRL+C - Operation aborted\n");
 
-			goto exit;
+			rc = CMD_RET_SUCCESS;
+			goto cleanup_register;
 		}
 	}
-exit:
+
+cleanup_register:
 	g_dnl_unregister();
+cleanup_board:
 	board_usb_cleanup(controller_index, USB_INIT_DEVICE);
-	return CMD_RET_SUCCESS;
+cleanup_ums_init:
+	ums_fini();
+
+	return rc;
 }
 
 U_BOOT_CMD(ums, 4, 1, do_usb_mass_storage,

drivers/usb/gadget/f_mass_storage.c

@@ -444,8 +444,9 @@ static void set_bulk_out_req_length(struct fsg_common *common,
 
 /*-------------------------------------------------------------------------*/
 
-struct ums *ums;
+static struct ums *ums;
-struct fsg_common *the_fsg_common;
+static int ums_count;
+static struct fsg_common *the_fsg_common;
 
 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
 {
@@ -772,7 +773,7 @@ static int do_read(struct fsg_common *common)
 		}
 
 		/* Perform the read */
-		rc = ums->read_sector(ums,
+		rc = ums[common->lun].read_sector(&ums[common->lun],
 				      file_offset / SECTOR_SIZE,
 				      amount / SECTOR_SIZE,
 				      (char __user *)bh->buf);
@@ -946,7 +947,7 @@ static int do_write(struct fsg_common *common)
 			amount = bh->outreq->actual;
 
 			/* Perform the write */
-			rc = ums->write_sector(ums,
+			rc = ums[common->lun].write_sector(&ums[common->lun],
 					       file_offset / SECTOR_SIZE,
 					       amount / SECTOR_SIZE,
 					       (char __user *)bh->buf);
@@ -1062,7 +1063,7 @@ static int do_verify(struct fsg_common *common)
 		}
 
 		/* Perform the read */
-		rc = ums->read_sector(ums,
+		rc = ums[common->lun].read_sector(&ums[common->lun],
 				      file_offset / SECTOR_SIZE,
 				      amount / SECTOR_SIZE,
 				      (char __user *)bh->buf);
@@ -1117,7 +1118,7 @@ static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
 	buf[4] = 31;		/* Additional length */
 				/* No special options */
 	sprintf((char *) (buf + 8), "%-8s%-16s%04x", (char*) vendor_id ,
-			ums->name, (u16) 0xffff);
+			ums[common->lun].name, (u16) 0xffff);
 
 	return 36;
 }
@@ -2456,7 +2457,7 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
 	int nluns, i, rc;
 
 	/* Find out how many LUNs there should be */
-	nluns = 1;
+	nluns = ums_count;
 	if (nluns < 1 || nluns > FSG_MAX_LUNS) {
 		printf("invalid number of LUNs: %u\n", nluns);
 		return ERR_PTR(-EINVAL);
@@ -2501,7 +2502,7 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
 	for (i = 0; i < nluns; i++) {
 		common->luns[i].removable = 1;
 
-		rc = fsg_lun_open(&common->luns[i], "");
+		rc = fsg_lun_open(&common->luns[i], ums[i].num_sectors, "");
 		if (rc)
 			goto error_luns;
 	}
@@ -2775,9 +2776,10 @@ int fsg_add(struct usb_configuration *c)
 	return fsg_bind_config(c->cdev, c, fsg_common);
 }
 
-int fsg_init(struct ums *ums_dev)
+int fsg_init(struct ums *ums_devs, int count)
 {
-	ums = ums_dev;
+	ums = ums_devs;
+	ums_count = count;
 
 	return 0;
 }

drivers/usb/gadget/storage_common.c

@@ -564,7 +564,8 @@ static struct usb_gadget_strings	fsg_stringtab = {
  * the caller must own fsg->filesem for writing.
  */
 
-static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
+static int fsg_lun_open(struct fsg_lun *curlun, unsigned int num_sectors,
+			const char *filename)
 {
 	int				ro;
 
@@ -572,8 +573,8 @@ static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
 	ro = curlun->initially_ro;
 
 	curlun->ro = ro;
-	curlun->file_length = ums->num_sectors << 9;
+	curlun->file_length = num_sectors << 9;
-	curlun->num_sectors = ums->num_sectors;
+	curlun->num_sectors = num_sectors;
 	debug("open backing file: %s\n", filename);
 
 	return 0;

include/usb_mass_storage.h

@@ -23,12 +23,10 @@ struct ums {
 	unsigned int start_sector;
 	unsigned int num_sectors;
 	const char *name;
-	block_dev_desc_t *block_dev;
+	block_dev_desc_t block_dev;
 };
 
-extern struct ums *ums;
+int fsg_init(struct ums *ums_devs, int count);
-
-int fsg_init(struct ums *);
 void fsg_cleanup(void);
 int fsg_main_thread(void *);
 int fsg_add(struct usb_configuration *c);