1 files changed, 99 insertions, 0 deletions

diff --git a/kernel/include/drivers/blockdev.h b/kernel/include/drivers/blockdev.h
new file mode 100644
index 0000000..d1b3062
--- /dev/null
+++ b/kernel/include/drivers/blockdev.h
@@ -0,0 +1,99 @@
+/*
+ *       FILE: dev_byte.h
+ *      DESCR: device management: block-oriented devices
+ */
+
+#pragma once
+
+#include "types.h"
+
+#include "drivers/dev.h"
+#include "util/list.h"
+
+#include "mm/mobj.h"
+#include "mm/page.h"
+
+#define BLOCK_SIZE PAGE_SIZE
+
+struct blockdev_ops;
+
+/*
+ * Represents a Weenix block device.
+ */
+typedef struct blockdev
+{
+    /* Fields that should be initialized by drivers: */
+    devid_t bd_id;
+
+    struct blockdev_ops *bd_ops;
+
+#ifdef NO
+    /* Fields that should be ignored by drivers: */
+    mobj_t bd_mobj;
+#endif
+
+    /* Link on the list of block-oriented devices */
+    list_link_t bd_link;
+} blockdev_t;
+
+typedef struct blockdev_ops
+{
+    /**
+     * Reads a block from the block device. This call will block.
+     *
+     * @param bdev the block device
+     * @param buf the memory into which to read the block (must be
+     *      page-aligned)
+     * @param loc the number of the block to start reading from
+     * @param count the number of blocks to read
+     * @return 0 on success, -errno on failure
+     */
+    long (*read_block)(blockdev_t *bdev, char *buf, blocknum_t loc,
+                       size_t block_count);
+
+    /**
+     * Writes a block to the block device. This call will block.
+     *
+     * @param bdev the block device
+     * @param buf the memory from which to write the block (must be
+     *      page-aligned)
+     * @param loc the number of the block to start writing at
+     * @param count the number of blocks to write
+     * @return 0 on success, -errno on failure
+     */
+    long (*write_block)(blockdev_t *bdev, const char *buf, blocknum_t loc,
+                        size_t block_count);
+} blockdev_ops_t;
+
+/**
+ * Initializes the block device subsystem.
+ */
+void blockdev_init(void);
+
+/**
+ * Registers a given block device.
+ *
+ * @param dev the block device to register
+ */
+long blockdev_register(blockdev_t *dev);
+
+/**
+ * Finds a block device with a given device id.
+ *
+ * @param id the device id of the block device to find
+ * @return the block device with the given id if it exists, or NULL if
+ * it cannot be found
+ */
+blockdev_t *blockdev_lookup(devid_t id);
+
+/**
+ * Cleans and frees all resident pages belonging to a given block
+ * device.
+ *
+ * @param dev the block device to flush
+ */
+void blockdev_flush_all(blockdev_t *dev);
+
+// restructure, perhaps, so that these don't have to be exported
+long blockdev_fill_pframe(mobj_t *mobj, pframe_t *pf);
+long blockdev_flush_pframe(mobj_t *mobj, pframe_t *pf);
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