svn commit: r316280 - head/sys/boot/efi/loader

[Toomas Soome]

Author: tsoome
Date: Thu Mar 30 16:31:35 2017
New Revision: 316280
URL: https://svnweb.freebsd.org/changeset/base/316280

Log:
  loader: simplify efi_zfs_probe and avoid double probing for zfs.
  
  The current efi_zfs_probe() is overcomplicated and can be made
  simpler. Still we need to pick up the device handle for our boot
  disk first, because the ESP does not have to be the first partition on the
  disk.
  
  Once we do have the handle for boot disk, we probe that disk with
  pointer for pool GUID.
  
  Reviewed by:	allanjude
  Approved by:	allanjude (mentor)
  Differential Revision:	https://reviews.freebsd.org/D10198

Modified:
  head/sys/boot/efi/loader/main.c

Modified: head/sys/boot/efi/loader/main.c
==============================================================================
--- head/sys/boot/efi/loader/main.c	Thu Mar 30 16:23:31 2017	(r316279)
+++ head/sys/boot/efi/loader/main.c	Thu Mar 30 16:31:35 2017	(r316280)
@@ -796,66 +796,45 @@ COMMAND_SET(fdt, "fdt", "flattened devic
 
 #ifdef EFI_ZFS_BOOT
 static void
-efipart_probe_img(pdinfo_list_t *hdi)
+efi_zfs_probe(void)
 {
+	pdinfo_list_t *hdi;
+	pdinfo_t *hd, *pd = NULL;
 	EFI_GUID imgid = LOADED_IMAGE_PROTOCOL;
 	EFI_LOADED_IMAGE *img;
-	pdinfo_t *hd, *pd = NULL;
+	EFI_HANDLE boot_disk = NULL;
 	char devname[SPECNAMELEN + 1];
+	uint64_t *guidp = NULL;
 
 	BS->HandleProtocol(IH, &imgid, (VOID**)&img);
 
-	/*
-	 * Search for the booted image device handle from hard disk list.
-	 * Note, this does also include usb sticks, and we assume there is no
-	 * ZFS on floppies nor cd.
-	 * However, we might have booted from floppy (unlikely) or CD,
-	 * so we should not surprised if we can not find the handle.
-	 */
+	/* Find the handle for the boot disk. */
+	hdi = efiblk_get_pdinfo_list(&efipart_hddev);
 	STAILQ_FOREACH(hd, hdi, pd_link) {
-		if (hd->pd_handle == img->DeviceHandle)
-			break;
 		STAILQ_FOREACH(pd, &hd->pd_part, pd_link) {
 			if (pd->pd_handle == img->DeviceHandle)
-				break;
+				boot_disk = hd->pd_handle;
 		}
-		if (pd != NULL)
-			break;
 	}
-	if (hd != NULL) {
-		if (pd != NULL) {
-			snprintf(devname, sizeof(devname), "%s%dp%d:",
-			    efipart_hddev.dv_name, hd->pd_unit, pd->pd_unit);
-		} else {
-			snprintf(devname, sizeof(devname), "%s%d:",
-			    efipart_hddev.dv_name, hd->pd_unit);
-		}
-		(void) zfs_probe_dev(devname, &pool_guid);
-	}
-}
 
-static void
-efi_zfs_probe(void)
-{
-	pdinfo_list_t *hdi;
-	pdinfo_t *hd;
-	char devname[SPECNAMELEN + 1];
-
-	hdi = efiblk_get_pdinfo_list(&efipart_hddev);
 	/*
-	 * First probe the boot device (from where loader.efi was read),
-	 * and set pool_guid global variable if we are booting from zfs.
-	 * Since loader is running, we do have an access to the device,
-	 * however, it might not be zfs.
+	 * We provide non-NULL guid pointer if the disk was used for boot,
+	 * and reset after the first found pool.
+	 * Technically this solution is not very correct, we assume the boot
+	 * pool is the first pool on this disk.
 	 */
 
-	if (pool_guid == 0)
-		efipart_probe_img(hdi);
-
 	STAILQ_FOREACH(hd, hdi, pd_link) {
-		snprintf(devname, sizeof(devname), "%s%d:",
-		    efipart_hddev.dv_name, hd->pd_unit);
-		(void) zfs_probe_dev(devname, NULL);
+		if (hd->pd_handle == boot_disk)
+			guidp = &pool_guid;
+
+		STAILQ_FOREACH(pd, &hd->pd_part, pd_link) {
+			snprintf(devname, sizeof(devname), "%s%dp%d:",
+			    efipart_hddev.dv_name, hd->pd_unit, pd->pd_unit);
+			(void) zfs_probe_dev(devname, guidp);
+			if (guidp != NULL && pool_guid != 0)
+				guidp = NULL;
+		}
 	}
 }
 #endif