Changeset 7a35204 in mainline

Timestamp:

2008-08-09T09:58:06Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

619e7c9b

Parents:

11c2ae5

Message:

First attempt at delivering the FAT16 read-only support.
Needless to say it doesn't work yet, but now it's only
the lurking bugs that need to be fixed.

File:

• uspace/srv/fs/fat/fat_ops.c (modified) (6 diffs)

uspace/srv/fs/fat/fat_ops.c

@@ -40 +40 @@
 #include <libfs.h>
 #include <ipc/ipc.h>
+#include <ipc/services.h>
+#include <ipc/devmap.h>
 #include <async.h>
 #include <errno.h>
@@ -48 +50 @@
 #include <assert.h>
 #include <futex.h>
+#include <sys/mman.h>
 
 #define BS_BLOCK                0
@@ -96 +99 @@
 }
 
+static int dev_phone = -1;              /* FIXME */
+static void *dev_buffer = NULL;         /* FIXME */
+
 /* TODO move somewhere else */
 typedef struct {
         void *data;
+        size_t size;
 } block_t;
 
 static block_t *block_get(dev_handle_t dev_handle, off_t offset, size_t bs)
 {
-        return NULL;    /* TODO */
+        /* FIXME */
+        block_t *b;
+        off_t bufpos = 0;
+        size_t buflen = 0;
+
+        assert(dev_phone != -1);
+        assert(dev_buffer);
+
+        b = malloc(sizeof(block_t));
+        if (!b)
+                return NULL;
+        
+        b->data = malloc(bs);
+        if (!b->data) {
+                free(b);
+                return NULL;
+        }
+        b->size = bs;
+
+        if (!libfs_blockread(dev_phone, dev_buffer, &bufpos, &buflen, &offset,
+            b->data, bs, bs)) {
+                free(b->data);
+                free(b);
+                return NULL;
+        }
+
+        return b;
 }
 
 static void block_put(block_t *block)
 {
-        /* TODO */
+        /* FIXME */
+        free(block->data);
+        free(block);
 }
 
@@ -569 +604 @@
         dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
         block_t *bb;
+        uint16_t bps;
         uint16_t rde;
         int rc;
 
+        /*
+         * For now, we don't bother to remember dev_handle, dev_phone or
+         * dev_buffer in some data structure. We use global variables because we
+         * know there will be at most one mount on this file system.
+         * Of course, this is a huge TODO item.
+         */
+        dev_buffer = mmap(NULL, BS_SIZE, PROTO_READ | PROTO_WRITE,
+            MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+        
+        if (!dev_buffer) {
+                ipc_answer_0(rid, ENOMEM);
+                return;
+        }
+
+        dev_phone = ipc_connect_me_to(PHONE_NS, SERVICE_DEVMAP,
+            DEVMAP_CONNECT_TO_DEVICE, dev_handle);
+
+        if (dev_phone < 0) {
+                munmap(dev_buffer, BS_SIZE);
+                ipc_answer_0(rid, dev_phone);
+                return;
+        }
+
+        rc = ipc_share_out_start(dev_phone, dev_buffer,
+            AS_AREA_READ | AS_AREA_WRITE);
+        if (rc != EOK) {
+                munmap(dev_buffer, BS_SIZE);
+                ipc_answer_0(rid, rc);
+                return;
+        }
+
         /* Read the number of root directory entries. */
         bb = block_get(dev_handle, BS_BLOCK, BS_SIZE);
+        bps = uint16_t_le2host(FAT_BS(bb)->bps);
         rde = uint16_t_le2host(FAT_BS(bb)->root_ent_max);
         block_put(bb);
 
+        if (bps != BS_SIZE) {
+                munmap(dev_buffer, BS_SIZE);
+                ipc_answer_0(rid, ENOTSUP);
+                return;
+        }
+
         rc = fat_idx_init_by_dev_handle(dev_handle);
         if (rc != EOK) {
+                munmap(dev_buffer, BS_SIZE);
                 ipc_answer_0(rid, rc);
                 return;
@@ -586 +661 @@
         fat_node_t *rootp = (fat_node_t *)malloc(sizeof(fat_node_t));
         if (!rootp) {
+                munmap(dev_buffer, BS_SIZE);
                 fat_idx_fini_by_dev_handle(dev_handle);
                 ipc_answer_0(rid, ENOMEM);
@@ -594 +670 @@
         fat_idx_t *ridxp = fat_idx_get_by_pos(dev_handle, FAT_CLST_ROOTPAR, 0);
         if (!ridxp) {
+                munmap(dev_buffer, BS_SIZE);
                 free(rootp);
                 fat_idx_fini_by_dev_handle(dev_handle);