Support BtrFS embedding.

* grub-core/fs/btrfs.c (grub_btrfs_embed) [GRUB_UTIL]: New function.
	(grub_btrfs_fs) [GRUB_UTIL]: Set embed.
	* include/grub/fs.h (grub_fs) [GRUB_UTIL]: New field embed.
	* util/grub-setup.c (setup): Use fs embedding if available.
	Add additional sanity check.

ChangeLog

@@ -1,3 +1,13 @@
+2011-11-05  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Support BtrFS embedding.
+
+	* grub-core/fs/btrfs.c (grub_btrfs_embed) [GRUB_UTIL]: New function.
+	(grub_btrfs_fs) [GRUB_UTIL]: Set embed.
+	* include/grub/fs.h (grub_fs) [GRUB_UTIL]: New field embed.
+	* util/grub-setup.c (setup): Use fs embedding if available.
+	Add additional sanity check.
+
 2011-11-05  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* util/grub-install.in: Fix condition for config_opt.

grub-core/fs/btrfs.c

@@ -1596,6 +1596,35 @@ grub_btrfs_label (grub_device_t device, char **label)
   return grub_errno;
 }
 
+#ifdef GRUB_UTIL
+static grub_err_t
+grub_btrfs_embed (grub_device_t device __attribute__ ((unused)),
+		  unsigned int *nsectors,
+		  grub_embed_type_t embed_type,
+		  grub_disk_addr_t **sectors)
+{
+  unsigned i;
+
+  if (embed_type != GRUB_EMBED_PCBIOS)
+    return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+		       "BtrFS curently supports only PC-BIOS embedding");
+
+  if (64 * 2 - 1 < *nsectors)
+    return grub_error (GRUB_ERR_OUT_OF_RANGE,
+		       "Your core.img is unusually large.  "
+		       "It won't fit in the embedding area.");
+
+  *nsectors = 64 * 2 - 1;
+  *sectors = grub_malloc (*nsectors * sizeof (**sectors));
+  if (!*sectors)
+    return grub_errno;
+  for (i = 0; i < *nsectors; i++)
+    (*sectors)[i] = i + 1;
+
+  return GRUB_ERR_NONE;
+}
+#endif
+
 static struct grub_fs grub_btrfs_fs = {
   .name = "btrfs",
   .dir = grub_btrfs_dir,
@@ -1605,6 +1634,7 @@ static struct grub_fs grub_btrfs_fs = {
   .uuid = grub_btrfs_uuid,
   .label = grub_btrfs_label,
 #ifdef GRUB_UTIL
+  .embed = grub_btrfs_embed,
   .reserved_first_sector = 1,
 #endif
 };

include/grub/fs.h

@@ -25,6 +25,10 @@
 #include <grub/types.h>
 
 #include <grub/list.h>
+/* For embedding types.  */
+#ifdef GRUB_UTIL
+#include <grub/partition.h>
+#endif
 
 /* Forward declaration is required, because of mutual reference.  */
 struct grub_file;
@@ -74,6 +78,11 @@ struct grub_fs
   grub_err_t (*mtime) (grub_device_t device, grub_int32_t *timebuf);
 
 #ifdef GRUB_UTIL
+  /* Determine sectors available for embedding.  */
+  grub_err_t (*embed) (grub_device_t device, unsigned int *nsectors,
+		       grub_embed_type_t embed_type,
+		       grub_disk_addr_t **sectors);
+
   /* Whether this filesystem reserves first sector for DOS-style boot.  */
   int reserved_first_sector;
 #endif

util/grub-setup.c

@@ -408,29 +408,44 @@ setup (const char *dir,
 
     free (tmp_img);
     
-    if (! dest_partmap)
+    if (! dest_partmap && ! fs)
       {
 	grub_util_warn (_("Attempting to install GRUB to a partitionless disk or to a partition.  This is a BAD idea."));
 	goto unable_to_embed;
       }
-    if (multiple_partmaps || fs)
+    if (multiple_partmaps || (dest_partmap && fs))
       {
 	grub_util_warn (_("Attempting to install GRUB to a disk with multiple partition labels or both partition label and filesystem.  This is not supported yet."));
 	goto unable_to_embed;
       }
 
-    if (!dest_partmap->embed)
+    if (dest_partmap && !dest_partmap->embed)
       {
 	grub_util_warn ("Partition style '%s' doesn't support embeding",
 			dest_partmap->name);
 	goto unable_to_embed;
       }
 
+    if (fs && !fs->embed)
+      {
+	grub_util_warn ("File system '%s' doesn't support embeding",
+			fs->name);
+	goto unable_to_embed;
+      }
+
     nsec = core_sectors;
+    if (dest_partmap)
       err = dest_partmap->embed (dest_dev->disk, &nsec,
 				 GRUB_EMBED_PCBIOS, &sectors);
-    if (nsec > 2 * core_sectors)
+    else
-      nsec = 2 * core_sectors;
+      err = fs->embed (dest_dev, &nsec,
+		       GRUB_EMBED_PCBIOS, &sectors);
+    if (!err && nsec < core_sectors)
+      {
+	err = grub_error (GRUB_ERR_OUT_OF_RANGE,
+			  "Your embedding area is unusually small.  "
+			  "core.img won't fit in it.");
+      }
     
     if (err)
       {
@@ -439,6 +454,9 @@ setup (const char *dir,
 	goto unable_to_embed;
       }
 
+    if (nsec > 2 * core_sectors)
+      nsec = 2 * core_sectors;
+
     /* Clean out the blocklists.  */
     block = first_block;
     while (block->len)