Changeset 1fbe064b in mainline

Timestamp:

2009-06-26T21:34:47Z (16 years ago)

Author:

Jiri Svoboda <jirik.svoboda@…>

Branches:

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

Children:

00fe6bb

Parents:

af65b72

Message:

Allow libblock to operate in write-through mode. With 'wtcache' mount option, FAT sets write-through mode on the cache.

Location:

uspace

Files:

• app/bdsh/cmds/modules/bdd/bdd.c (modified) (1 diff)
• lib/libblock/libblock.c (modified) (7 diffs)
• lib/libblock/libblock.h (modified) (2 diffs)
• srv/fs/fat/fat_ops.c (modified) (3 diffs)

uspace/app/bdsh/cmds/modules/bdd/bdd.c

@@ -103 +103 @@
         }
 
-        rc = block_cache_init(handle, BLOCK_SIZE, 2);
+        rc = block_cache_init(handle, BLOCK_SIZE, 2, CACHE_MODE_WB);
         if (rc != EOK) {
                 printf("Error: could not init block cache.\n");

uspace/lib/libblock/libblock.c

@@ -66 +66 @@
         hash_table_t block_hash;
         link_t free_head;
+        enum cache_mode mode;
 } cache_t;
 
@@ -80 +81 @@
 } devcon_t;
 
+static int write_block(devcon_t *devcon, bn_t boff, size_t block_size,
+    const void *src);
+
 static devcon_t *devcon_search(dev_handle_t dev_handle)
 {
@@ -251 +255 @@
 };
 
-int block_cache_init(dev_handle_t dev_handle, size_t size, unsigned blocks)
+int block_cache_init(dev_handle_t dev_handle, size_t size, unsigned blocks,
+    enum cache_mode mode)
 {
         devcon_t *devcon = devcon_search(dev_handle);
@@ -267 +272 @@
         cache->block_size = size;
         cache->block_count = blocks;
+        cache->mode = mode;
 
         if (!hash_table_create(&cache->block_hash, CACHE_BUCKETS, 1,
@@ -414 +420 @@
         devcon_t *devcon = devcon_search(block->dev_handle);
         cache_t *cache;
+        int rc;
 
         assert(devcon);
@@ -427 +434 @@
                  */
                 list_append(&block->free_link, &cache->free_head);
+                if (cache->mode != CACHE_MODE_WB && block->dirty) {
+                        rc = write_block(devcon, block->boff, block->size,
+                            block->data);
+                        assert(rc == EOK);
+
+                        block->dirty = false;
+                }
         }
         fibril_mutex_unlock(&block->lock);
@@ -491 +505 @@
 }
 
+/** Write block to block device.
+ *
+ * @param devcon        Device connection.
+ * @param boff          Block index.
+ * @param block_size    Block size.
+ * @param src           Buffer containing the data to write.
+ *
+ * @return              EOK on success or negative error code on failure.
+ */
+static int write_block(devcon_t *devcon, bn_t boff, size_t block_size,
+    const void *src)
+{
+        ipcarg_t retval;
+        int rc;
+
+        assert(devcon);
+        memcpy(devcon->com_area, src, block_size);
+        
+        rc = async_req_2_1(devcon->dev_phone, BD_WRITE_BLOCK,
+            boff, block_size, &retval);
+        if ((rc != EOK) || (retval != EOK))
+                return (rc != EOK ? rc : (int) retval);
+
+        return EOK;
+}
+
 /** @}
  */

uspace/lib/libblock/libblock.h

@@ -85 +85 @@
 } block_t;
 
+/** Caching mode */
+enum cache_mode {
+        /** Write-Through */
+        CACHE_MODE_WT,
+        /** Write-Back */
+        CACHE_MODE_WB
+};
+
 extern int block_init(dev_handle_t, size_t);
 extern void block_fini(dev_handle_t);
@@ -91 +99 @@
 extern void *block_bb_get(dev_handle_t);
 
-extern int block_cache_init(dev_handle_t, size_t, unsigned);
+extern int block_cache_init(dev_handle_t, size_t, unsigned, enum cache_mode);
 
 extern block_t *block_get(dev_handle_t, bn_t, int flags);

uspace/srv/fs/fat/fat_ops.c

@@ -771 +771 @@
 {
         dev_handle_t dev_handle = (dev_handle_t) IPC_GET_ARG1(*request);
+        enum cache_mode cmode;
         fat_bs_t *bs;
         uint16_t bps;
@@ -798 +799 @@
         opts[size] = '\0';
 
+        /* Check for option enabling write through. */
+        if (str_cmp(opts, "wtcache") == 0)
+                cmode = CACHE_MODE_WT;
+        else
+                cmode = CACHE_MODE_WB;
+
         /* initialize libblock */
         rc = block_init(dev_handle, BS_SIZE);
@@ -827 +834 @@
 
         /* Initialize the block cache */
-        rc = block_cache_init(dev_handle, bps, 0 /* XXX */);
+        rc = block_cache_init(dev_handle, bps, 0 /* XXX */, cmode);
         if (rc != EOK) {
                 block_fini(dev_handle);