driver/ata: separate out from the fsroot driver

1 files changed, 76 insertions, 0 deletions

diff --git a/src/kernel/arch/amd64/driver/pata.c b/src/kernel/arch/amd64/driver/pata.c
new file mode 100644
index 0000000..a21fc2b
--- /dev/null
+++ b/src/kernel/arch/amd64/driver/pata.c
@@ -0,0 +1,76 @@
+#include <camellia/errno.h>
+#include <kernel/arch/amd64/ata.h>
+#include <kernel/arch/amd64/driver/pata.h>
+#include <kernel/arch/amd64/driver/util.h>
+#include <kernel/mem/virt.h>
+#include <kernel/panic.h>
+#include <kernel/vfs/request.h>
+#include <shared/mem.h>
+
+const int root_id = 100;
+
+static void accept(struct vfs_request *req);
+static struct vfs_backend backend = BACKEND_KERN(accept);
+
+void pata_init(void) {
+	ata_init();
+	vfs_mount_root_register("/ata", &backend);
+}
+
+
+static bool exacteq(struct vfs_request *req, const char *str) {
+	size_t len = strlen(str);
+	assert(req->input.kern);
+	return req->input.len == len && !memcmp(req->input.buf_kern, str, len);
+}
+
+static void accept(struct vfs_request *req) {
+	int ret;
+	long id = (long __force)req->id;
+	switch (req->type) {
+		case VFSOP_OPEN:
+			if (!req->input.kern) panic_invalid_state();
+			ret = -ENOENT;
+			if (exacteq(req, "/")) ret = root_id;
+			else if (exacteq(req, "/0")) ret = 0;
+			else if (exacteq(req, "/1")) ret = 1;
+			else if (exacteq(req, "/2")) ret = 2;
+			else if (exacteq(req, "/3")) ret = 3;
+			vfsreq_finish_short(req, ret);
+			break;
+
+		case VFSOP_READ:
+			if (id == root_id) {
+				// TODO use dirbuild
+				char list[8] = {};
+				size_t len = 0;
+				for (int i = 0; i < 4; i++) {
+					if (ata_available(i)) {
+						list[len] = '0' + i;
+						len += 2;
+					}
+				}
+				vfsreq_finish_short(req, req_readcopy(req, list, len));
+				break;
+			}
+			// TODO ata size get
+			if (req->offset < 0) {
+				vfsreq_finish_short(req, -ENOSYS);
+				break;
+			}
+			char buf[512]; /* stupid */
+			uint32_t sector = req->offset / 512;
+			size_t len = min(req->output.len, 512 - ((size_t)req->offset & 511));
+			ata_read(id, sector, buf);
+			virt_cpy_to(req->caller->pages, req->output.buf, buf, len);
+			vfsreq_finish_short(req, len);
+			break;
+
+		case VFSOP_WRITE:
+			panic_unimplemented();
+
+		default:
+			vfsreq_finish_short(req, -ENOSYS);
+			break;
+	}
+}