Attachment 903280 Details for Bug 1094489 – v2 add support for btrfs when grub2 is bootloader

[patch] v2 add support for btrfs when grub2 is bootloader

0002-v2-add-support-for-btrfs-when-grub2-is-bootloader.patch (text/plain), 9.56 KB, created by Gene Czarcinski on 2014-06-08 13:18:02 UTC

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Creator: Gene Czarcinski

Created: 2014-06-08 13:18:02 UTC

Size: 9.56 KB

patch

obsolete

>From f8996145227caca0bc0ab53ae817303a8972b38f Mon Sep 17 00:00:00 2001
>From: Gene Czarcinski <gczarcinski@gmail.com>
>Date: Sat, 7 Jun 2014 14:41:51 -0400
>Subject: [PATCH 2/4] v2 add support for btrfs when grub2 is bootloader
>Content-Type: text/plain; charset="utf-8"
>Content-Transfer-Encoding: 8bit
>
>This patch adds getSubvolPrefix() for handling a btrfs subvol
>prefix on the filenames for grub2.  If get_Root_Specifier() results
>in a NULL rootspec, then getSubvolPrefix() is executed to extract any
>btrfs subvol prefix.  With this modification, booting off
>/boot on a btrfs subvol is supported.
>
>To determine if booting is to be performed off a btrfs volume
>or subvolume, the lines of the entry are scanned to detect
>if "insmod btrfs" is present.  If it is, then btrfs is assumed.
>
>If the kernel filename includes only one slash, then there is
>no btrfs prefix.  Otherwise, the first part defined by "/../"
>will be the btrfs prefix if booting btrfs.  Unless, of course,
>there are 2 slashes in the filename but bootPrefix is zero length
>in which case we are booting off a btrfs volume!
>
>Besides the kernel, the subvol prefix must also be on the
>initrd filename.  The subvol prefix for initrd is based on
>the entry's kernel's filename.  Note that the lines of
>the entry must be scanned to determine if we are booting on
>btrfs.
>
>Code was added to addLine(tmpl() so that the subvol prefix not added
>for an initrd since updateInitrd() does that already.
>---
> grubby.c | 110 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 107 insertions(+), 3 deletions(-)
>
>diff --git a/grubby.c b/grubby.c
>index fa5eac9..eaf53e3 100644
>--- a/grubby.c
>+++ b/grubby.c
>@@ -690,6 +690,8 @@ static int lineWrite(FILE * out, struct singleLine * line,
> static int getNextLine(char ** bufPtr, struct singleLine * line,
> 		       struct configFileInfo * cfi);
> static char * getRootSpecifier(char * str);
>+static char * getSubvolPrefix(struct singleLine * line, char * str);
>+static char * findBootPrefix(void);
> static void requote(struct singleLine *line, struct configFileInfo * cfi);
> static void insertElement(struct singleLine * line,
> 			  const char * item, int insertHere,
>@@ -1843,6 +1845,58 @@ static int endswith(const char *s, char c)
> 	return s[slen] == c;
> }
> 
>+
>+/* extract any btrfs prefix on filename */
>+/* the passed string is elements[1] */
>+static char * getSubvolPrefix(struct singleLine * line, char * str) {
>+    char *idx,    *svPrefix = NULL;
>+    int  slashcnt = 0;
>+    const char * bootPrefix = findBootPrefix();
>+
>+static int btrfsBootFlag = 0;
>+
>+    if (btrfsBootFlag == 0){
>+	for (; line; line = line->next) {
>+	    dbgPrintf("checkForBtrfsBoot(%s)\n",
>+		line->numElements >0 ? line->elements[0].item : "");
>+	    if (line->numElements >1) {
>+		if ((strcasecmp(line->elements[0].item,"insmod")==0) &&
>+		    (strcasecmp(line->elements[1].item,"btrfs")==0)) {
>+		    dbgPrintf("NOTE: booting from a btrfs volume or subvolume\n");
>+		    btrfsBootFlag = -1;
>+		    break;
>+		}
>+	    }
>+	}
>+    }
>+
>+    idx = str;
>+    while (*idx) {
>+	if (*idx == '/')
>+	    slashcnt++;
>+	idx++;
>+    }
>+
>+    dbgPrintf("getSubvolPrefix(): btrfsBootFlag=%i, slashcnt=%i, str='%s', bootPrefix='%s'\n",
>+	btrfsBootFlag, slashcnt, str, bootPrefix);
>+
>+    if ((btrfsBootFlag == 0) ||
>+	(slashcnt == 0) ||
>+	(slashcnt == 1))
>+	return NULL;
>+
>+    if ((slashcnt == 2) && (strlen(bootPrefix) == 0))
>+	return NULL;
>+
>+    if ((btrfsBootFlag == -1) && (*str == '/')) {
>+        idx = svPrefix = strdup(str);
>+	idx++;
>+        while(*idx && (*idx != '/') && (!isspace(*idx))) idx++;
>+	*idx = '\0';  /* strip off the second slash */
>+    }
>+    return svPrefix;
>+}
>+
> int suitableImage(struct singleEntry * entry, const char * bootPrefix,
> 		  int skipRemoved, int flags) {
>     struct singleLine * line;
>@@ -1873,14 +1927,21 @@ int suitableImage(struct singleEntry * entry, const char * bootPrefix,
> 	    return 1;
>     }
> 
>+    dbgPrintf("suitableImage(), bootPrefix='%s', type='%s'\n",
>+		bootPrefix, line->elements[0].item);
>     fullName = alloca(strlen(bootPrefix) + 
> 		      strlen(line->elements[1].item) + 1);
>     rootspec = getRootSpecifier(line->elements[1].item);
>+    if (rootspec == NULL) {
>+	rootspec = getSubvolPrefix(entry->lines, line->elements[1].item);
>+    }
>     int rootspec_offset = rootspec ? strlen(rootspec) : 0;
>     int hasslash = endswith(bootPrefix, '/') ||
>     	beginswith(line->elements[1].item + rootspec_offset, '/');
>     sprintf(fullName, "%s%s%s", bootPrefix, hasslash ? "" : "/",
>             line->elements[1].item + rootspec_offset);
>+    dbgPrintf("suitbleImage(): fullName='%s' root/subvol prefix='%s'\n",
>+		fullName, (rootspec != NULL) ? rootspec : "");
>     if (access(fullName, R_OK)) {
> 	notSuitablePrintf(entry, 0, "access to %s failed\n", fullName);
> 	return 0;
>@@ -2052,11 +2113,17 @@ struct singleEntry * findEntryByPath(struct grubConfig * config,
> 		if (line && line->type != LT_MENUENTRY &&
> 			line->numElements >= 2) {
> 		    rootspec = getRootSpecifier(line->elements[1].item);
>+		    if (rootspec == NULL) {
>+			rootspec = getSubvolPrefix(entry->lines, line->elements[1].item);
>+		    }
> 		    if (!strcmp(line->elements[1].item + 
> 				((rootspec != NULL) ? strlen(rootspec) : 0),
> 				kernel + strlen(prefix)))
> 			break;
> 		}
>+		if(line->type == LT_MENUENTRY)
>+		    dbgPrintf("findEntryByPath: got:'%s', wanted='%s'\n",
>+				line->elements[1].item, kernel);
> 		if(line->type == LT_MENUENTRY &&
> 			!strcmp(line->elements[1].item, kernel))
> 		    break;
>@@ -2202,7 +2269,7 @@ struct singleEntry * findTemplate(struct grubConfig * cfg, const char * prefix,
>     return NULL;
> }
> 
>-char * findBootPrefix(void) {
>+static char * findBootPrefix(void) {
>     struct stat sb, sb2;
> 
>     stat("/", &sb);
>@@ -2829,6 +2896,9 @@ struct singleLine * addLineTmpl(struct singleEntry * entry,
> 	/* but try to keep the rootspec from the template... sigh */
> 	if (tmplLine->type & (LT_HYPER|LT_KERNEL|LT_MBMODULE|LT_INITRD|LT_KERNEL_EFI|LT_INITRD_EFI|LT_KERNEL_16|LT_INITRD_16)) {
> 	    char * rootspec = getRootSpecifier(tmplLine->elements[1].item);
>+	    if ((rootspec == NULL) && (tmplLine->type & (LT_HYPER|LT_KERNEL|LT_KERNEL_EFI|LT_KERNEL_16))) {
>+		rootspec = getSubvolPrefix(entry->lines, tmplLine->elements[1].item);
>+	    }
> 	    if (rootspec != NULL) {
> 		free(newLine->elements[1].item);
> 		newLine->elements[1].item = 
>@@ -3358,23 +3428,40 @@ int addMBInitrd(struct grubConfig * cfg, const char *newMBKernel,
>     struct singleEntry * entry;
>     struct singleLine * line, * kernelLine, *endLine = NULL;
>     int index = 0;
>+    char * svPrefix = NULL;
>+    char * newInitrd = NULL;
> 
>     if (!image) return 0;
>+    dbgPrintf("addMBInitrd(), image='%s', prefix='%s', initrd='%s'\n",
>+		image, prefix, initrd);
> 
>     for (; (entry = findEntryByPath(cfg, newMBKernel, prefix, &index)); index++) {
>         kernelLine = getLineByType(LT_MBMODULE, entry->lines);
>         if (!kernelLine) continue;
>+	dbgPrintf("... index=%i, kernel: %s '%s'\n", index,
>+		kernelLine->elements[0].item,
>+		kernelLine->elements[1].item);
>+	svPrefix = getSubvolPrefix(entry->lines, kernelLine->elements[1].item);
> 
>         if (prefix) {
>             int prefixLen = strlen(prefix);
>             if (!strncmp(initrd, prefix, prefixLen))
>                 initrd += prefixLen;
>         }
>+	if (svPrefix) {
>+	    newInitrd = alloca(strlen(svPrefix) + strlen(initrd) + 2);
>+	    strcpy(newInitrd, svPrefix);
>+            strcat(newInitrd, initrd);
>+	} else
>+	    newInitrd = (char *)initrd;
>+	dbgPrintf("... updated initrd='%s'\n", newInitrd);
> 	endLine = getLineByType(LT_ENTRY_END, entry->lines);
> 	if (endLine)
> 	    removeLine(entry, endLine);
>         line = addLine(entry, cfg->cfi, preferredLineType(LT_MBMODULE,cfg->cfi),
>-			kernelLine->indent, initrd);
>+			kernelLine->indent, newInitrd);
>+	if (svPrefix)
>+	    free(svPrefix);
>         if (!line)
> 	    return 1;
> 	if (endLine) {
>@@ -3394,12 +3481,20 @@ int updateInitrd(struct grubConfig * cfg, const char * image,
>     struct singleEntry * entry;
>     struct singleLine * line, * kernelLine, *endLine = NULL;
>     int index = 0;
>+    char * svPrefix = NULL;
>+    char * newInitrd = NULL;
> 
>     if (!image) return 0;
>+    dbgPrintf("updateInitrd(), image='%s', prefix='%s', initrd='%s'\n",
>+		image, prefix, initrd);
> 
>     for (; (entry = findEntryByPath(cfg, image, prefix, &index)); index++) {
>         kernelLine = getLineByType(LT_KERNEL|LT_KERNEL_EFI|LT_KERNEL_16, entry->lines);
>         if (!kernelLine) continue;
>+	dbgPrintf("... index=%i, kernel: %s '%s'\n", index,
>+		kernelLine->elements[0].item,
>+		kernelLine->elements[1].item);
>+	svPrefix = getSubvolPrefix(entry->lines, kernelLine->elements[1].item);
> 
>         line = getLineByType(LT_INITRD|LT_INITRD_EFI|LT_INITRD_16, entry->lines);
>         if (line)
>@@ -3409,6 +3504,13 @@ int updateInitrd(struct grubConfig * cfg, const char * image,
>             if (!strncmp(initrd, prefix, prefixLen))
>                 initrd += prefixLen;
>         }
>+	if (svPrefix) {
>+	    newInitrd = alloca(strlen(svPrefix) + strlen(initrd) + 2);
>+	    strcpy(newInitrd, svPrefix);
>+            strcat(newInitrd, initrd);
>+	} else
>+	    newInitrd = (char *)initrd;
>+	dbgPrintf("... updated initrd='%s'\n", newInitrd);
> 	endLine = getLineByType(LT_ENTRY_END, entry->lines);
> 	if (endLine)
> 	    removeLine(entry, endLine);
>@@ -3426,7 +3528,9 @@ int updateInitrd(struct grubConfig * cfg, const char * image,
> 	    default:
> 	        lt = preferredLineType(LT_INITRD, cfg->cfi);
> 	}
>-        line = addLine(entry, cfg->cfi, lt, kernelLine->indent, initrd);
>+        line = addLine(entry, cfg->cfi, lt, kernelLine->indent, newInitrd);
>+	if (svPrefix)
>+	    free(svPrefix);
>         if (!line)
> 	    return 1;
> 	if (endLine) {
>-- 
>1.9.3
>

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Attachments on bug 1094489: 892670 | 892671 | 893044 | 893046 | 903279 | 903280 | 903281 | 903283 | 906996 | 906997 | 906998 | 907052