disk: get_device_and_partition() "auto" partition and cleanup
[platform/kernel/u-boot.git] / disk / part.c
index f659cc3..0dd4b0f 100644 (file)
@@ -24,6 +24,7 @@
 #include <common.h>
 #include <command.h>
 #include <ide.h>
+#include <malloc.h>
 #include <part.h>
 
 #undef PART_DEBUG
@@ -70,7 +71,7 @@ static const struct block_drvr block_drvr[] = {
 
 DECLARE_GLOBAL_DATA_PTR;
 
-block_dev_desc_t *get_dev(char* ifname, int dev)
+block_dev_desc_t *get_dev(const char *ifname, int dev)
 {
        const struct block_drvr *drvr = block_drvr;
        block_dev_desc_t* (*reloc_get_dev)(int dev);
@@ -97,7 +98,7 @@ block_dev_desc_t *get_dev(char* ifname, int dev)
        return NULL;
 }
 #else
-block_dev_desc_t *get_dev(char* ifname, int dev)
+block_dev_desc_t *get_dev(const char *ifname, int dev)
 {
        return NULL;
 }
@@ -288,6 +289,7 @@ void init_part (block_dev_desc_t * dev_desc)
            return;
        }
 #endif
+       dev_desc->part_type = PART_TYPE_UNKNOWN;
 }
 
 
@@ -441,3 +443,199 @@ int get_partition_info(block_dev_desc_t *dev_desc, int part
 
        return -1;
 }
+
+int get_device(const char *ifname, const char *dev_str,
+              block_dev_desc_t **dev_desc)
+{
+       char *ep;
+       int dev;
+
+       dev = simple_strtoul(dev_str, &ep, 16);
+       if (*ep) {
+               printf("** Bad device specification %s %s **\n",
+                      ifname, dev_str);
+               return -1;
+       }
+
+       *dev_desc = get_dev(ifname, dev);
+       if (!(*dev_desc) || ((*dev_desc)->type == DEV_TYPE_UNKNOWN)) {
+               printf("** Bad device %s %s **\n", ifname, dev_str);
+               return -1;
+       }
+
+       return dev;
+}
+
+#define PART_UNSPECIFIED -2
+#define PART_AUTO -1
+#define MAX_SEARCH_PARTITIONS 16
+int get_device_and_partition(const char *ifname, const char *dev_part_str,
+                            block_dev_desc_t **dev_desc,
+                            disk_partition_t *info, int allow_whole_dev)
+{
+       int ret = -1;
+       const char *part_str;
+       char *dup_str = NULL;
+       const char *dev_str;
+       int dev;
+       char *ep;
+       int p;
+       int part;
+       disk_partition_t tmpinfo;
+
+       /* If no dev_part_str, use bootdevice environment variable */
+       if (!dev_part_str)
+               dev_part_str = getenv("bootdevice");
+
+       /* If still no dev_part_str, it's an error */
+       if (!dev_part_str) {
+               printf("** No device specified **\n");
+               goto cleanup;
+       }
+
+       /* Separate device and partition ID specification */
+       part_str = strchr(dev_part_str, ':');
+       if (part_str) {
+               dup_str = strdup(dev_part_str);
+               dup_str[part_str - dev_part_str] = 0;
+               dev_str = dup_str;
+               part_str++;
+       } else {
+               dev_str = dev_part_str;
+       }
+
+       /* Look up the device */
+       dev = get_device(ifname, dev_str, dev_desc);
+       if (dev < 0)
+               goto cleanup;
+
+       /* Convert partition ID string to number */
+       if (!part_str || !*part_str) {
+               part = PART_UNSPECIFIED;
+       } else if (!strcmp(part_str, "auto")) {
+               part = PART_AUTO;
+       } else {
+               /* Something specified -> use exactly that */
+               part = (int)simple_strtoul(part_str, &ep, 16);
+               /*
+                * Less than whole string converted,
+                * or request for whole device, but caller requires partition.
+                */
+               if (*ep || (part == 0 && !allow_whole_dev)) {
+                       printf("** Bad partition specification %s %s **\n",
+                           ifname, dev_part_str);
+                       goto cleanup;
+               }
+       }
+
+       /*
+        * No partition table on device,
+        * or user requested partition 0 (entire device).
+        */
+       if (((*dev_desc)->part_type == PART_TYPE_UNKNOWN) ||
+           (part == 0)) {
+               if (!(*dev_desc)->lba) {
+                       printf("** Bad device size - %s %s **\n", ifname,
+                              dev_str);
+                       goto cleanup;
+               }
+
+               /*
+                * If user specified a partition ID other than 0,
+                * or the calling command only accepts partitions,
+                * it's an error.
+                */
+               if ((part > 0) || (!allow_whole_dev)) {
+                       printf("** No partition table - %s %s **\n", ifname,
+                              dev_str);
+                       goto cleanup;
+               }
+
+               info->start = 0;
+               info->size = (*dev_desc)->lba;
+               info->blksz = (*dev_desc)->blksz;
+               info->bootable = 0;
+#ifdef CONFIG_PARTITION_UUIDS
+               info->uuid[0] = 0;
+#endif
+
+               ret = 0;
+               goto cleanup;
+       }
+
+       /*
+        * Now there's known to be a partition table,
+        * not specifying a partition means to pick partition 1.
+        */
+       if (part == PART_UNSPECIFIED)
+               part = 1;
+
+       /*
+        * If user didn't specify a partition number, or did specify something
+        * other than "auto", use that partition number directly.
+        */
+       if (part != PART_AUTO) {
+               ret = get_partition_info(*dev_desc, part, info);
+               if (ret) {
+                       printf("** Invalid partition %d **\n", part);
+                       goto cleanup;
+               }
+       } else {
+               /*
+                * Find the first bootable partition.
+                * If none are bootable, fall back to the first valid partition.
+                */
+               part = 0;
+               for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
+                       ret = get_partition_info(*dev_desc, p, info);
+                       if (ret)
+                               continue;
+
+                       /*
+                        * First valid partition, or new better partition?
+                        * If so, save partition ID.
+                        */
+                       if (!part || info->bootable)
+                               part = p;
+
+                       /* Best possible partition? Stop searching. */
+                       if (info->bootable)
+                               break;
+
+                       /*
+                        * We now need to search further for best possible.
+                        * If we what we just queried was the best so far,
+                        * save the info since we over-write it next loop.
+                        */
+                       if (part == p)
+                               tmpinfo = *info;
+               }
+               /* If we found any acceptable partition */
+               if (part) {
+                       /*
+                        * If we searched all possible partition IDs,
+                        * return the first valid partition we found.
+                        */
+                       if (p == MAX_SEARCH_PARTITIONS + 1)
+                               *info = tmpinfo;
+                       ret = 0;
+               } else {
+                       printf("** No valid partitions found **\n");
+                       goto cleanup;
+               }
+       }
+       if (strncmp((char *)info->type, BOOT_PART_TYPE, sizeof(info->type)) != 0) {
+               printf("** Invalid partition type \"%.32s\""
+                       " (expect \"" BOOT_PART_TYPE "\")\n",
+                       info->type);
+               ret  = -1;
+               goto cleanup;
+       }
+
+       ret = part;
+       goto cleanup;
+
+cleanup:
+       free(dup_str);
+       return ret;
+}