Attachment 201423 Details for Bug 235206 – Patch to add an automatic GPT recovery feature to gptzfsboot

[patch] Patch to add an automatic GPT recovery feature to gptzfsboot

patch-zgptrecover_stand_i386_zfsboot_zfsboot.c.patch (text/plain), 3.88 KB, created by Emrion on 2019-01-26 20:49:10 UTC

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Creator: Emrion

Created: 2019-01-26 20:49:10 UTC

Size: 3.88 KB

patch

obsolete

>--- zfsboot.c.ori	2019-01-26 14:04:23.570240000 +0100
>+++ zfsboot.c	2019-01-26 20:45:26.031322000 +0100
>@@ -23,6 +23,7 @@
> #include <sys/diskmbr.h>
> #ifdef GPT
> #include <sys/gpt.h>
>+#include "crc32.h"
> #endif
> #include <sys/reboot.h>
> #include <sys/queue.h>
>@@ -529,11 +530,97 @@
> 	return (size * DEV_BSIZE);
> }
> 
>+#ifdef GPT
>+static int
>+zgptread(struct dsk *dskp, uint64_t lba, struct gpt_hdr *hdr)
>+{
>+	/* Most of this code comes from gpt.c */
>+
>+	/* Don't want to include "gpt.h" just for MAXTBLENTS */
>+	const uint32_t maxtbents = 128;
>+
>+	/* Extract and verify the header */
>+	char* secbuf = dmadat->secbuf;
>+	uint32_t crc;
>+	if (drvread(dskp, secbuf, lba, 1)) return (-1);
>+	bcopy(secbuf, hdr, sizeof(*hdr));
>+	if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
>+	    hdr->hdr_lba_self != lba || hdr->hdr_revision < 0x00010000 ||
>+	    hdr->hdr_entsz < sizeof(struct gpt_ent) ||
>+	    hdr->hdr_entries > maxtbents || DEV_BSIZE % hdr->hdr_entsz != 0) 
>+		return (-1);
>+	
>+	crc = hdr->hdr_crc_self;
>+	hdr->hdr_crc_self = 0;
>+	if (crc32(hdr, hdr->hdr_size) != crc)  return (-1);
>+	hdr->hdr_crc_self = crc;
>+	
>+	/* Check the partition table */
>+	char *table = malloc(hdr->hdr_entries * hdr->hdr_entsz);
>+	if (!table) return (-1);
>+	int n_sect = DEV_BSIZE / hdr->hdr_entsz;
>+	n_sect = hdr->hdr_entries / n_sect;
>+	for (int i = 0; i < n_sect; i++) {
>+		if (drvread(dskp, secbuf, hdr->hdr_lba_table + i, 1)) {
>+			free(table);
>+			return (-1);
>+		}
>+		bcopy(secbuf, table + i * DEV_BSIZE, DEV_BSIZE);
>+	}
>+	if (crc32(table, hdr->hdr_entries * hdr->hdr_entsz) != hdr->hdr_crc_table) {
>+		free(table); 
>+		return (-1);
>+	} 
>+	free(table);
>+	return (0);
>+}
>+
>+static int
>+zgpt_recover(struct dsk *dskp, struct gpt_hdr *hdr_prim,
>+                const struct gpt_hdr *hdr_back)
>+{
>+	printf("%s: trying to recover GPT...\n", BOOTPROG);
>+	char* secbuf = dmadat->secbuf;
>+	const uint64_t head_prim_lba = 1;
>+	const uint64_t table_prim_lba = 2;
>+                
>+	/* Copy partition table backup -> primary */
>+	int n_sect = DEV_BSIZE / hdr_back->hdr_entsz;
>+	n_sect = hdr_back->hdr_entries / n_sect;
>+	for (int i = 0; i < n_sect; i++) {
>+		if (drvread(dskp, secbuf, hdr_back->hdr_lba_table + i, 1))
>+			goto zrecover_failed;
>+		if (drvwrite(dskp, secbuf, table_prim_lba + i, 1))
>+			goto zrecover_failed;
>+	}
>+                
>+	/* Set GPT primary header with backup header */
>+	*hdr_prim = *hdr_back;
>+	hdr_prim->hdr_crc_self = 0;
>+	hdr_prim->hdr_lba_self = head_prim_lba;
>+	hdr_prim->hdr_lba_alt = hdr_back->hdr_lba_self;
>+	hdr_prim->hdr_lba_table = table_prim_lba;
>+	hdr_prim->hdr_crc_self = crc32(hdr_prim, hdr_prim->hdr_size);
>+	bzero(secbuf, DEV_BSIZE);
>+	bcopy(hdr_prim, secbuf, hdr_prim->hdr_size);
>+	if (drvwrite(dskp, secbuf, hdr_prim->hdr_lba_self, 1))
>+		goto zrecover_failed;
>+            
>+	printf("%s: GPT recovering -> SUCCESS\n", BOOTPROG);
>+	return (0);
>+                
>+zrecover_failed:
>+	printf("%s: GPT recovering -> FAILED\n", BOOTPROG);
>+	return (-1);
>+}
>+
>+#endif /* GPT */
>+
> static void
> probe_drive(struct zfsdsk *zdsk)
> {
> #ifdef GPT
>-    struct gpt_hdr hdr;
>+    struct gpt_hdr hdr, hdr_back;
>     struct gpt_ent *ent;
>     unsigned part, entries_per_sec;
>     daddr_t slba;
>@@ -581,7 +668,15 @@
>     /*
>      * First check for GPT.
>      */
>-    if (drvread(&zdsk->dsk, sec, 1, 1)) {
>+	const uint64_t head_prim_lba = 1;
>+	if (zgptread(&zdsk->dsk, head_prim_lba, &hdr)) {
>+		uint64_t altlba = drvsize(&zdsk->dsk);
>+		if (altlba > 0 && !zgptread(&zdsk->dsk, altlba-1, &hdr_back)) {
>+			if (zgpt_recover(&zdsk->dsk, &hdr, &hdr_back))
>+				goto trymbr;
>+		} else goto trymbr;
>+	}
>+/*    if (drvread(&zdsk->dsk, sec, 1, 1)) {
> 	return;
>     }
>     memcpy(&hdr, sec, sizeof(hdr));
>@@ -589,7 +684,7 @@
> 	hdr.hdr_lba_self != 1 || hdr.hdr_revision < 0x00010000 ||
> 	hdr.hdr_entsz < sizeof(*ent) || DEV_BSIZE % hdr.hdr_entsz != 0) {
> 	goto trymbr;
>-    }
>+    }*/
> 
>     /*
>      * Probe all GPT partitions for the presence of ZFS pools. We

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Attachments on bug 235206: 201403 | 201423