[block] Describe all SAN devices via ACPI tables

Describe all SAN devices via ACPI tables such as the iBFT.  For tables
that can describe only a single device (i.e. the aBFT and sBFT), one
table is installed per device.  For multi-device tables (i.e. the
iBFT), all devices are described in a single table.

An underlying SAN device connection may be closed at the time that we
need to construct an ACPI table.  We therefore introduce the concept
of an "ACPI descriptor" which enables the SAN boot code to maintain an
opaque pointer to the underlying object, and an "ACPI model" which can
build tables from a list of such descriptors.  This separates the
lifecycles of ACPI descriptions from the lifecycles of the block
device interfaces, and allows for construction of the ACPI tables even
if the block device interface has been closed.

For a multipath SAN device, iPXE will wait until sufficient
information is available to describe all devices but will not wait for
all paths to connect successfully.  For example: with a multipath
iSCSI boot iPXE will wait until at least one path has become available
and name resolution has completed on all other paths.  We do this
since the iBFT has to include IP addresses rather than DNS names.  We
will commence booting without waiting for the inactive paths to either
become available or close; this avoids unnecessary boot delays.

Note that the Linux kernel will refuse to accept an iBFT with more
than two NIC or target structures.  We therefore describe only the
NICs that are actually required in order to reach the described
targets.  Any iBFT with at most two targets is therefore guaranteed to
describe at most two NICs.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 19 insertions, 6 deletions

diff --git a/src/core/dummy_sanboot.c b/src/core/dummy_sanboot.c
index 64d5206f..08180852 100644
--- a/src/core/dummy_sanboot.c
+++ b/src/core/dummy_sanboot.c
@@ -38,10 +38,11 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  * @v drive		Drive number
  * @v uris		List of URIs
  * @v count		Number of URIs
+ * @v flags		Flags
  * @ret drive		Drive number, or negative error
  */
 static int dummy_san_hook ( unsigned int drive, struct uri **uris,
-			    unsigned int count ) {
+			    unsigned int count, unsigned int flags ) {
 	struct san_device *sandev;
 	int rc;
 
@@ -51,10 +52,9 @@ static int dummy_san_hook ( unsigned int drive, struct uri **uris,
 		rc = -ENOMEM;
 		goto err_alloc;
 	}
-	sandev->drive = drive;
 
 	/* Register SAN device */
-	if ( ( rc = register_sandev ( sandev ) ) != 0 ) {
+	if ( ( rc = register_sandev ( sandev, drive, flags ) ) != 0 ) {
 		DBGC ( sandev, "SAN %#02x could not register: %s\n",
 		       sandev->drive, strerror ( rc ) );
 		goto err_register;
@@ -102,15 +102,28 @@ static int dummy_san_boot ( unsigned int drive __unused ) {
 }
 
 /**
- * Describe dummy SAN device
+ * Install ACPI table
  *
- * @v drive		Drive number
+ * @v acpi		ACPI description header
+ * @ret rc		Return status code
  */
-static int dummy_san_describe ( unsigned int drive __unused ) {
+static int dummy_install ( struct acpi_header *acpi ) {
 
+	DBGC ( acpi, "ACPI table %s:\n", acpi_name ( acpi->signature ) );
+	DBGC_HDA ( acpi, 0, acpi, le32_to_cpu ( acpi->length ) );
 	return 0;
 }
 
+/**
+ * Describe dummy SAN device
+ *
+ * @ret rc		Return status code
+ */
+static int dummy_san_describe ( void ) {
+
+	return acpi_install ( dummy_install );
+}
+
 PROVIDE_SANBOOT ( dummy, san_hook, dummy_san_hook );
 PROVIDE_SANBOOT ( dummy, san_unhook, dummy_san_unhook );
 PROVIDE_SANBOOT ( dummy, san_boot, dummy_san_boot );