Changeset e27b89a in mainline for uspace/srv/part/mbr_part/mbr_part.c

Timestamp:

2009-09-01T21:27:41Z (15 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

0712ff2, 9aa54d4a

Parents:

440b0ce

Message:

Remove fixed limitation on partition count.

File:

• uspace/srv/part/mbr_part/mbr_part.c (modified) (15 diffs)

uspace/srv/part/mbr_part/mbr_part.c

@@ -59 +59 @@
 #include <bool.h>
 #include <byteorder.h>
+#include <assert.h>
 #include <macros.h>
 #include <task.h>
@@ -70 +71 @@
         /** Boot record signature */
         BR_SIGNATURE    = 0xAA55,
-
-        /** Maximum number of partitions */
-        MAX_PART        = 64
 };
 
@@ -81 +79 @@
 
 /** Partition */
-typedef struct {
+typedef struct part {
         /** Primary partition entry is in use */
         bool present;
@@ -90 +88 @@
         /** Device representing the partition (outbound device) */
         dev_handle_t dev;
+        /** Points to next partition structure. */
+        struct part *next;
 } part_t;
 
@@ -130 +130 @@
 static dev_handle_t indev_handle;
 
-static part_t primary[MAX_PART];
+/** List of partitions. This structure is an empty head. */
+static part_t plist_head;
 
 static int mbr_init(const char *dev_name);
 static int mbr_part_read(void);
+static part_t *mbr_part_new(void);
 static void mbr_pte_to_part(uint32_t base, const pt_entry_t *pte, part_t *part);
 static void mbr_connection(ipc_callid_t iid, ipc_call_t *icall);
@@ -140 +142 @@
 static int mbr_bsa_translate(part_t *p, uint64_t ba, size_t cnt, uint64_t *gba);
 
-/** Total number of partitions entries in @c primary (including non-present). */
-static int total_part;
-
 int main(int argc, char **argv)
 {
@@ -170 +169 @@
         dev_handle_t dev;
         uint64_t size_mb;
+        part_t *part;
 
         rc = devmap_device_get_handle(dev_name, &indev_handle, 0);
@@ -208 +208 @@
         }
 
-        /* Create partition devices. */
-        for (i = 0; i < total_part; ++i) {
+        /*
+         * Create partition devices.
+         */
+        i = 0;
+        part = plist_head.next;
+
+        while (part != NULL) {
                 /* Skip absent partitions. */
-                if (!primary[i].present)
+                if (!part->present) {
+                        part = part->next;
+                        ++i;
                         continue;
+                }
 
                 asprintf(&name, "%sp%d", dev_name, i);
@@ -225 +233 @@
                 }
 
-                size_mb = (primary[i].length * block_size + 1024 * 1024 - 1)
+                size_mb = (part->length * block_size + 1024 * 1024 - 1)
                     / (1024 * 1024);
                 printf(NAME ": Registered device %s: %llu blocks %llu MB.\n",
-                    name, primary[i].length, size_mb);
-
-                primary[i].dev = dev;
+                    name, part->length, size_mb);
+
+                part->dev = dev;
                 free(name);
+
+                part = part->next;
+                ++i;
         }
 
@@ -246 +257 @@
         part_t *ext_part, cp;
         uint32_t base;
+        part_t *prev, *p;
 
         brb = malloc(sizeof(br_block_t));
@@ -270 +282 @@
 
         ext_part = NULL;
+        plist_head.next = NULL;
+        prev = &plist_head;
 
         for (i = 0; i < N_PRIMARY; ++i) {
-                mbr_pte_to_part(0, &brb->pte[i], &primary[i]);
+                p = mbr_part_new();
+                if (p == NULL)
+                        return ENOMEM;
+
+                mbr_pte_to_part(0, &brb->pte[i], p);
+                prev->next = p;
+                prev = p;
 
                 if (brb->pte[i].ptype == PT_EXTENDED) {
-                        primary[i].present = false;
-                        ext_part = &primary[i];
+                        p->present = false;
+                        ext_part = p;
                 }
         }
@@ -312 +332 @@
                 }
 
+                p = mbr_part_new();
+                if (p == NULL)
+                        return ENOMEM;
+
                 /* First PTE is the logical partition itself. */
-                mbr_pte_to_part(base, &brb->pte[0], &primary[i]);
-                ++i;
+                mbr_pte_to_part(base, &brb->pte[0], p);
+                prev->next = p;
+                prev = p;
 
                 /* Second PTE describes next chain element. */
                 mbr_pte_to_part(base, &brb->pte[1], &cp);
-        } while (cp.present && i < MAX_PART);
-
-        total_part = i;
+        } while (cp.present);
 
         return EOK;
+}
+
+/** Allocate a new @c part_t structure. */
+static part_t *mbr_part_new(void)
+{
+        return malloc(sizeof(part_t));
 }
 
@@ -338 +367 @@
         part->present = (sa != 0 || len != 0) ? true : false;
         part->dev = 0;
+        part->next = NULL;
 }
 
@@ -352 +382 @@
         uint64_t ba;
         size_t cnt;
-        int pidx, i;
         part_t *part;
 
@@ -358 +387 @@
         dh = IPC_GET_ARG1(*icall);
 
-        /* Determine which partition device is the client connecting to. */
-        pidx = -1;
-        for (i = 0; i < total_part; i++)
-                if (primary[i].dev == dh)
-                        pidx = i;
-
-        if (pidx < 0/* || disk[disk_id].present == false*/) {
+        /* 
+         * Determine which partition device is the client connecting to.
+         * A linear search is not terribly fast, but we only do this
+         * once for each connection.
+         */
+        part = plist_head.next;
+        while (part != NULL && part->dev != dh)
+                part = part->next;
+
+        if (part == NULL) {
                 ipc_answer_0(iid, EINVAL);
                 return;
         }
 
-        part = &primary[pidx];
+        assert(part->present == true);
 
         /* Answer the IPC_M_CONNECT_ME_TO call. */