Implement a proper block layer with partition support.

[pintos-anon] / src / devices / block.h

diff --git a/src/devices/block.h b/src/devices/block.h
new file mode 100644 (file)
index 0000000..21732d6
--- /dev/null
+++ b/src/devices/block.h
@@ -0,0 +1,74 @@
+#ifndef DEVICES_BLOCK_H
+#define DEVICES_BLOCK_H
+
+#include <stddef.h>
+#include <inttypes.h>
+
+/* Size of a block device sector in bytes.
+   All IDE disks use this sector size, as do most USB and SCSI
+   disks.  It's not worth it to try to cater to other sector
+   sizes in Pintos (yet). */
+#define BLOCK_SECTOR_SIZE 512
+
+/* Index of a block device sector.
+   Good enough for devices up to 2 TB. */
+typedef uint32_t block_sector_t;
+
+/* Format specifier for printf(), e.g.:
+   printf ("sector=%"PRDSNu"\n", sector); */
+#define PRDSNu PRIu32
+\f
+/* Higher-level interface for file systems, etc. */
+
+struct block;
+
+/* Type of a block device. */
+enum block_type
+  {
+    /* Block device types that play a role in Pintos. */
+    BLOCK_KERNEL,                /* Pintos OS kernel. */
+    BLOCK_FILESYS,               /* File system. */
+    BLOCK_SCRATCH,               /* Scratch. */
+    BLOCK_SWAP,                  /* Swap. */
+    BLOCK_ROLE_CNT,
+
+    /* Other kinds of block devices that Pintos may see but does
+       not interact with. */
+    BLOCK_RAW = BLOCK_ROLE_CNT,  /* "Raw" device with unidentified contents. */
+    BLOCK_FOREIGN,               /* Owned by non-Pintos operating system. */
+    BLOCK_CNT                    /* Number of Pintos block types. */
+  };
+
+const char *block_type_name (enum block_type);
+
+/* Finding block devices. */
+struct block *block_get_role (enum block_type);
+void block_set_role (enum block_type, struct block *);
+struct block *block_get_by_name (const char *name);
+
+struct block *block_first (void);
+struct block *block_next (struct block *);
+
+/* Block device operations. */
+block_sector_t block_size (struct block *);
+void block_read (struct block *, block_sector_t, void *);
+void block_write (struct block *, block_sector_t, const void *);
+const char *block_name (struct block *);
+enum block_type block_type (struct block *);
+
+/* Statistics. */
+void block_print_stats (void);
+\f
+/* Lower-level interface to block device drivers. */
+
+struct block_operations
+  {
+    void (*read) (void *aux, block_sector_t, void *buffer);
+    void (*write) (void *aux, block_sector_t, const void *buffer);
+  };
+
+struct block *block_register (const char *name, enum block_type,
+                              const char *extra_info, block_sector_t size,
+                              const struct block_operations *, void *aux);
+
+#endif /* devices/block.h */