[RFC] grub-install: allow none or multiple install devices on PC BIOS

* [RFC] grub-install: allow none or multiple install devices on PC BIOS
@ 2015-05-08 18:53 Andrei Borzenkov
  2015-05-12 10:52 ` Michael Chang
  2016-02-12 18:41 ` Vladimir 'φ-coder/phcoder' Serbinenko
  0 siblings, 2 replies; 10+ messages in thread
From: Andrei Borzenkov @ 2015-05-08 18:53 UTC (permalink / raw)
  To: grub-devel

There are two main applications.

1. Omit install device to create generic image intended for chainloading
from other master loader. Such image can be put on any device (or file
system) and will still be able to find its $root. Currently even with
--no-bootsector grub-install optimizes image by skipping UUID search if
possible.

2. Redundant installation on multi-device filesystem, RAID or similar.
This allows both optimizing image w.r.t. to using --prefix vs. load.cfg
as well as creating image just once.

Patch allows transparently use none or multiple installation devices,
similar to

grub_devices="/dev/sda /dev/sda1 /dev/sdb"
grub-install $grub_devices

where grub_devices can be empty and still do the right thing.

This is work in progress, although it is functionally complete and just
needs some cleanups.

Comments?

---
 grub-core/kern/disk.c |   5 +-
 include/grub/disk.h   |   2 +
 util/grub-install.c   | 217 +++++++++++++++++++++++++++++++-------------------
 3 files changed, 143 insertions(+), 81 deletions(-)

diff --git a/grub-core/kern/disk.c b/grub-core/kern/disk.c
index 789f8c0..56f16b4 100644
--- a/grub-core/kern/disk.c
+++ b/grub-core/kern/disk.c
@@ -168,7 +168,10 @@ grub_disk_dev_unregister (grub_disk_dev_t dev)
 
 /* Return the location of the first ',', if any, which is not
    escaped by a '\'.  */
-static const char *
+#if !defined (GRUB_UTIL)
+static
+#endif
+const char *
 find_part_sep (const char *name)
 {
   const char *p = name;
diff --git a/include/grub/disk.h b/include/grub/disk.h
index b385af8..b2081eb 100644
--- a/include/grub/disk.h
+++ b/include/grub/disk.h
@@ -256,6 +256,8 @@ void grub_ldm_fini (void);
 void grub_mdraid09_fini (void);
 void grub_mdraid1x_fini (void);
 void grub_diskfilter_fini (void);
+extern const char *find_part_sep (const char *);
+
 #endif
 
 #endif /* ! GRUB_DISK_HEADER */
diff --git a/util/grub-install.c b/util/grub-install.c
index 7b394c9..bb6532c 100644
--- a/util/grub-install.c
+++ b/util/grub-install.c
@@ -57,7 +57,10 @@ static char *target;
 static int removable = 0;
 static int recheck = 0;
 static int update_nvram = 1;
-static char *install_device = NULL;
+static char **install_devices = NULL;
+static char **install_drives = NULL;
+static int n_install_devices;
+static int n_allocated_devices;
 static char *debug_image = NULL;
 static char *rootdir = NULL;
 static char *bootdir = NULL;
@@ -234,9 +237,12 @@ argp_parser (int key, char *arg, struct argp_state *state)
       return 0;
 
     case ARGP_KEY_ARG:
-      if (install_device)
-	grub_util_error ("%s", _("More than one install device?"));
-      install_device = xstrdup (arg);
+      if (n_install_devices >= n_allocated_devices)
+	{
+	  n_allocated_devices += 16;
+	  install_devices = xrealloc (install_devices, n_allocated_devices);
+	}
+      install_devices[n_install_devices++] = xstrdup (arg);
       return 0;
 
     default:
@@ -534,25 +540,55 @@ probe_cryptodisk_uuid (grub_disk_t disk)
 }
 
 static int
-is_same_disk (const char *a, const char *b)
+same_disks (char **root_devs)
 {
-  while (1)
+  int i;
+
+  for (i = 0; i < n_install_devices; i++)
     {
-      if ((*a == ',' || *a == '\0') && (*b == ',' || *b == '\0'))
-	return 1;
-      if (*a != *b)
-	return 0;
-      if (*a == '\\')
+      char **d;
+      const char *p1 = find_part_sep (install_drives[i]);
+      size_t len1 = p1 ? p1 - install_drives[i] : strlen (install_drives[i]);
+
+      for (d = root_devs; *d; d++)
 	{
-	  if (a[1] != b[1])
-	    return 0;
-	  a += 2;
-	  b += 2;
-	  continue;
+	  const char *p2 = find_part_sep (*d);
+	  size_t len2 = p2 ? p2 - *d : strlen (*d);
+
+	  if (len1 == len2 &&
+	      strncmp (install_drives[i], *d, len1) == 0)
+	    break;
 	}
-      a++;
-      b++;
+      if (!*d)
+	return 0;
+    }
+
+  return 1;
+}
+
+static int
+same_partitions (char **root_devs)
+{
+  const char *first_part;
+  char **p;
+
+  if (!root_devs[1])
+    return 1;
+
+  first_part = find_part_sep (root_devs[0]);
+  for (p = root_devs + 1; *p; p++)
+    {
+      const char *part = find_part_sep (*p);
+
+      if ((first_part == NULL) ^ (part == NULL))
+	return 0;
+      if (!first_part && !part)
+	continue;
+      if (strcmp (first_part, part))
+	return 0;
     }
+
+  return 1;
 }
 
 static char *
@@ -835,6 +871,8 @@ main (int argc, char *argv[])
   int efidir_is_mac = 0;
   int is_prep = 0;
   const char *pkgdatadir;
+  size_t i;
+
 
   grub_util_host_init (&argc, &argv);
   product_version = xstrdup (PACKAGE_VERSION);
@@ -926,12 +964,26 @@ main (int argc, char *argv[])
   switch (platform)
     {
     case GRUB_INSTALL_PLATFORM_I386_PC:
+      break;
+
+    default:
+      if (n_install_devices > 1)
+	grub_util_error ("%s", _("More than one install device?"));
+      break;
+    }
+
+  switch (platform)
+    {
+    case GRUB_INSTALL_PLATFORM_I386_PC:
+      if (!install_devices)
+	install_bootsector = 0;
+      break;
     case GRUB_INSTALL_PLATFORM_SPARC64_IEEE1275:
-      if (!install_device)
+      if (!install_devices)
 	grub_util_error ("%s", _("install device isn't specified"));
       break;
     case GRUB_INSTALL_PLATFORM_POWERPC_IEEE1275:
-      if (install_device)
+      if (install_devices)
 	is_prep = 1;
       break;
     case GRUB_INSTALL_PLATFORM_MIPS_ARC:
@@ -952,8 +1004,11 @@ main (int argc, char *argv[])
     case GRUB_INSTALL_PLATFORM_MIPS_QEMU_MIPS:
     case GRUB_INSTALL_PLATFORM_I386_XEN:
     case GRUB_INSTALL_PLATFORM_X86_64_XEN:
-      free (install_device);
-      install_device = NULL;
+      for (i = 0; i < n_install_devices; i++)
+	free (install_devices[i]);
+      free (install_devices);
+      install_devices = NULL;
+      n_install_devices = n_allocated_devices = 0;
       break;
 
       /* pacify warning.  */
@@ -996,11 +1051,6 @@ main (int argc, char *argv[])
       is_efi = 1;
       break;
     default:
-      is_efi = 0;
-      break;
-
-      /* pacify warning.  */
-    case GRUB_INSTALL_PLATFORM_MAX:
       break;
     }
 
@@ -1009,8 +1059,6 @@ main (int argc, char *argv[])
   if (is_efi)
     {
       grub_fs_t fs;
-      free (install_device);
-      install_device = NULL;
       if (!efidir)
 	{
 	  char *d = grub_util_path_concat (2, bootdir, "efi");
@@ -1045,7 +1093,9 @@ main (int argc, char *argv[])
       if (!efidir_device_names || !efidir_device_names[0])
 	grub_util_error (_("cannot find a device for %s (is /dev mounted?)"),
 			     efidir);
-      install_device = efidir_device_names[0];
+      /* FIXME free install_devices */
+      /* We will use just the first device */
+      install_devices = efidir_device_names;
 
       for (curdev = efidir_device_names; *curdev; curdev++)
 	  grub_util_pull_device (*curdev);
@@ -1207,7 +1257,9 @@ main (int argc, char *argv[])
 	  if (grub_strcmp (fs->name, "hfs") == 0
 	      || grub_strcmp (fs->name, "hfsplus") == 0)
 	    {
-	      install_device = macppcdir_device_names[0];
+	      /* FIXME free install_devices */
+	      /* We just use the first one */
+	      install_devices = macppcdir_device_names;
 	      is_prep = 0;
 	    }
 	}
@@ -1318,35 +1370,37 @@ main (int argc, char *argv[])
 	      debug_image);
     }
   char *prefix_drive = NULL;
-  char *install_drive = NULL;
 
-  if (install_device)
+  if (install_devices)
     {
-      if (install_device[0] == '('
-	  && install_device[grub_strlen (install_device) - 1] == ')')
-        {
-	  size_t len = grub_strlen (install_device) - 2;
-	  install_drive = xmalloc (len + 1);
-	  memcpy (install_drive, install_device + 1, len);
-	  install_drive[len] = '\0';
-        }
-      else
-	{
-	  grub_util_pull_device (install_device);
-	  install_drive = grub_util_get_grub_dev (install_device);
-	  if (!install_drive)
-	    grub_util_error (_("cannot find a GRUB drive for %s.  Check your device.map"),
-			     install_device);
-	}
+      install_drives = xmalloc (n_install_devices * sizeof (*install_drives));
+
+      for (i = 0; i < n_install_devices; i++)
+	if (install_devices[i][0] == '('
+	    && install_devices[i][grub_strlen (install_devices[i]) - 1] == ')')
+	  {
+	    size_t len = grub_strlen (install_devices[i]) - 2;
+	    install_drives[i] = xmalloc (len + 1);
+	    memcpy (install_drives[i], install_devices[i] + 1, len);
+	    install_drives[i][len] = '\0';
+	  }
+	else
+	  {
+	    grub_util_pull_device (install_devices[i]);
+	    install_drives[i] = grub_util_get_grub_dev (install_devices[i]);
+	    if (!install_drives[i])
+	      grub_util_error (_("cannot find a GRUB drive for %s.  Check your device.map"),
+			       install_devices[i]);
+	  }
     }
 
   if (!have_abstractions)
     {
       if ((disk_module && grub_strcmp (disk_module, "biosdisk") != 0)
-	  || grub_drives[1]
-	  || (!install_drive
+	  || (grub_drives[1] && !same_partitions (grub_drives))
+	  || (!install_drives
 	      && platform != GRUB_INSTALL_PLATFORM_POWERPC_IEEE1275)
-	  || (install_drive && !is_same_disk (grub_drives[0], install_drive))
+	  || (install_drives && !same_disks (grub_drives))
 	  || !have_bootdev (platform))
 	{
 	  char *uuid = NULL;
@@ -1656,24 +1710,27 @@ main (int argc, char *argv[])
 					      "boot.img");
 	grub_install_copy_file (boot_img_src, boot_img, 1);
 
-	grub_util_info ("%sgrub-bios-setup %s %s %s %s %s --directory='%s' --device-map='%s' '%s'",
-			/* TRANSLATORS: This is a prefix in the log to indicate that usually
-			   a command would be executed but due to an option was skipped.  */
-			install_bootsector ? "" : _("NOT RUNNING: "),
-			allow_floppy ? "--allow-floppy " : "",
-			verbosity ? "--verbose " : "",
-			force ? "--force " : "",
-			!fs_probe ? "--skip-fs-probe" : "",
-			!add_rs_codes ? "--no-rs-codes" : "",
-			platdir,
-			device_map,
-			install_device);
-			
-	/*  Now perform the installation.  */
-	if (install_bootsector)
-	  grub_util_bios_setup (platdir, "boot.img", "core.img",
-				install_drive, force,
-				fs_probe, allow_floppy, add_rs_codes);
+	for (i = 0; i < n_install_devices; i++)
+	  {
+	    grub_util_info ("%sgrub-bios-setup %s %s %s %s %s --directory='%s' --device-map='%s' '%s'",
+			    /* TRANSLATORS: This is a prefix in the log to indicate that usually
+			       a command would be executed but due to an option was skipped.  */
+			    install_bootsector ? "" : _("NOT RUNNING: "),
+			    allow_floppy ? "--allow-floppy " : "",
+			    verbosity ? "--verbose " : "",
+			    force ? "--force " : "",
+			    !fs_probe ? "--skip-fs-probe" : "",
+			    !add_rs_codes ? "--no-rs-codes" : "",
+			    platdir,
+			    device_map,
+			    install_devices[i]);
+
+	    /*  Now perform the installation.  */
+	    if (install_bootsector)
+	      grub_util_bios_setup (platdir, "boot.img", "core.img",
+				    install_drives[i], force,
+				    fs_probe, allow_floppy, add_rs_codes);
+	  }
 	break;
       }
     case GRUB_INSTALL_PLATFORM_SPARC64_IEEE1275:
@@ -1693,12 +1750,12 @@ main (int argc, char *argv[])
 			!fs_probe ? "--skip-fs-probe" : "",
 			platdir,
 			device_map,
-			install_drive);
+			install_drives[0]);
 			
 	/*  Now perform the installation.  */
 	if (install_bootsector)
 	  grub_util_sparc_setup (platdir, "boot.img", "core.img",
-				 install_device, force,
+				 install_devices[0], force,
 				 fs_probe, allow_floppy,
 				 0 /* unused */ );
 	break;
@@ -1734,7 +1791,7 @@ main (int argc, char *argv[])
 
 	  fill_core_services (core_services);
 
-	  ins_dev = grub_device_open (install_drive);
+	  ins_dev = grub_device_open (install_drives[0]);
 
 	  bless (ins_dev, core_services, 0);
 
@@ -1745,7 +1802,7 @@ main (int argc, char *argv[])
 
 	      partno = ins_dev->disk->partition
 		? ins_dev->disk->partition->number + 1 : 0;
-	      dev = grub_util_get_os_disk (install_device);
+	      dev = grub_util_get_os_disk (install_devices[0]);
 	      grub_install_register_ieee1275 (0, dev, partno,
 					      "\\\\BootX");
 	    }
@@ -1757,10 +1814,10 @@ main (int argc, char *argv[])
 	  break;
 	}
       /* If a install device is defined, copy the core.elf to PReP partition.  */
-      if (is_prep && install_device && install_device[0])
+      if (is_prep)
 	{
 	  grub_device_t ins_dev;
-	  ins_dev = grub_device_open (install_drive);
+	  ins_dev = grub_device_open (install_drives[0]);
 	  if (!ins_dev || !is_prep_partition (ins_dev))
 	    {
 	      grub_util_error ("%s", _("the chosen partition is not a PReP partition"));
@@ -1772,13 +1829,13 @@ main (int argc, char *argv[])
 	    }
 	  else
 	    {
-	      char *s = xasprintf ("dd if=/dev/zero of=%s", install_device);
+	      char *s = xasprintf ("dd if=/dev/zero of=%s", install_devices[0]);
 	      grub_util_error (_("the PReP partition is not empty. If you are sure you want to use it, run dd to clear it: `%s'"),
 			       s);
 	    }
 	  grub_device_close (ins_dev);
 	  if (update_nvram)
-	    grub_install_register_ieee1275 (1, grub_util_get_os_disk (install_device),
+	    grub_install_register_ieee1275 (1, grub_util_get_os_disk (install_devices[0]),
 					    0, NULL);
 	  break;
       }
@@ -1798,7 +1855,7 @@ main (int argc, char *argv[])
 	}
       break;
     case GRUB_INSTALL_PLATFORM_MIPS_ARC:
-      grub_install_sgi_setup (install_device, imgfile, "grub");
+      grub_install_sgi_setup (install_devices[0], imgfile, "grub");
       break;
 
     case GRUB_INSTALL_PLATFORM_I386_EFI:
@@ -1834,7 +1891,7 @@ main (int argc, char *argv[])
 
 	  fill_core_services(core_services);
 
-	  ins_dev = grub_device_open (install_drive);
+	  ins_dev = grub_device_open (install_drives[0]);
 
 	  bless (ins_dev, boot_efi, 1);
 	  if (!removable && update_nvram)
-- 
tg: (0725881..) e/optional-install-device (depends on: master)


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