vbatts
/
grub
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
grub/grub-core/disk/lvm.c

897 lines
20 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* lvm.c - module to read Logical Volumes. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2006,2007,2008,2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/dl.h>
#include <grub/disk.h>
#include <grub/mm.h>
#include <grub/err.h>
#include <grub/misc.h>
#include <grub/lvm.h>
#ifdef GRUB_UTIL
#include <grub/emu/misc.h>
#endif
GRUB_MOD_LICENSE ("GPLv3+");
static struct grub_lvm_vg *vg_list;
static int lv_count;
/* Go the string STR and return the number after STR. *P will point
at the number. In case STR is not found, *P will be NULL and the
return value will be 0. */
static int
grub_lvm_getvalue (char **p, char *str)
{
*p = grub_strstr (*p, str);
if (! *p)
return 0;
*p += grub_strlen (str);
return grub_strtoul (*p, NULL, 10);
}
#if 0
static int
grub_lvm_checkvalue (char **p, char *str, char *tmpl)
{
int tmpllen = grub_strlen (tmpl);
*p = grub_strstr (*p, str);
if (! *p)
return 0;
*p += grub_strlen (str);
if (**p != '"')
return 0;
return (grub_memcmp (*p + 1, tmpl, tmpllen) == 0 && (*p)[tmpllen + 1] == '"');
}
#endif
static int
grub_lvm_check_flag (char *p, char *str, char *flag)
{
int len_str = grub_strlen (str), len_flag = grub_strlen (flag);
while (1)
{
char *q;
p = grub_strstr (p, str);
if (! p)
return 0;
p += len_str;
if (grub_memcmp (p, " = [", sizeof (" = [") - 1) != 0)
continue;
q = p + sizeof (" = [") - 1;
while (1)
{
while (grub_isspace (*q))
q++;
if (*q != '"')
return 0;
q++;
if (grub_memcmp (q, flag, len_flag) == 0 && q[len_flag] == '"')
return 1;
while (*q != '"')
q++;
q++;
if (*q == ']')
return 0;
q++;
}
}
}
static int
grub_lvm_iterate (int (*hook) (const char *name))
{
struct grub_lvm_vg *vg;
for (vg = vg_list; vg; vg = vg->next)
{
struct grub_lvm_lv *lv;
if (vg->lvs)
for (lv = vg->lvs; lv; lv = lv->next)
if (lv->visible && hook (lv->name))
return 1;
}
return 0;
}
#ifdef GRUB_UTIL
static grub_disk_memberlist_t
grub_lvm_memberlist (grub_disk_t disk)
{
struct grub_lvm_lv *lv = disk->data;
grub_disk_memberlist_t list = NULL, tmp;
struct grub_lvm_pv *pv;
if (lv->vg->pvs)
for (pv = lv->vg->pvs; pv; pv = pv->next)
{
if (!pv->disk)
grub_util_error ("Couldn't find PV %s. Check your device.map",
pv->name);
tmp = grub_malloc (sizeof (*tmp));
tmp->disk = pv->disk;
tmp->next = list;
list = tmp;
}
return list;
}
#endif
static grub_err_t
grub_lvm_open (const char *name, grub_disk_t disk)
{
struct grub_lvm_vg *vg;
struct grub_lvm_lv *lv = NULL;
for (vg = vg_list; vg; vg = vg->next)
{
if (vg->lvs)
for (lv = vg->lvs; lv; lv = lv->next)
if (! grub_strcmp (lv->name, name))
break;
if (lv)
break;
}
if (! lv)
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "unknown LVM device %s", name);
disk->id = lv->number;
disk->data = lv;
disk->total_sectors = lv->size;
return 0;
}
static void
grub_lvm_close (grub_disk_t disk __attribute ((unused)))
{
return;
}
static grub_err_t
read_lv (struct grub_lvm_lv *lv, grub_disk_addr_t sector,
grub_size_t size, char *buf);
static grub_err_t
read_node (const struct grub_lvm_node *node, grub_disk_addr_t sector,
grub_size_t size, char *buf)
{
/* Check whether we actually know the physical volume we want to
read from. */
if (node->pv)
{
if (node->pv->disk)
return grub_disk_read (node->pv->disk, sector + node->pv->start, 0,
size << GRUB_DISK_SECTOR_BITS, buf);
else
return grub_error (GRUB_ERR_UNKNOWN_DEVICE,
"physical volume %s not found", node->pv->name);
}
if (node->lv)
return read_lv (node->lv, sector, size, buf);
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "unknown node '%s'", node->name);
}
static grub_err_t
read_lv (struct grub_lvm_lv *lv, grub_disk_addr_t sector,
grub_size_t size, char *buf)
{
grub_err_t err = 0;
struct grub_lvm_vg *vg = lv->vg;
struct grub_lvm_segment *seg = lv->segments;
struct grub_lvm_node *node;
grub_uint64_t offset;
grub_uint64_t extent;
unsigned int i;
if (!lv)
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "unknown volume");
extent = grub_divmod64 (sector, vg->extent_size, NULL);
/* Find the right segment. */
for (i = 0; i < lv->segment_count; i++)
{
if ((seg->start_extent <= extent)
&& ((seg->start_extent + seg->extent_count) > extent))
{
break;
}
seg++;
}
if (i == lv->segment_count)
return grub_error (GRUB_ERR_READ_ERROR, "incorrect segment");
switch (seg->type)
{
case GRUB_LVM_STRIPED:
if (seg->node_count == 1)
{
/* This segment is linear, so that's easy. We just need to find
out the offset in the physical volume and read SIZE bytes
from that. */
struct grub_lvm_node *stripe = seg->nodes;
grub_uint64_t seg_offset; /* Offset of the segment in PV device. */
node = stripe;
seg_offset = ((grub_uint64_t) stripe->start
* (grub_uint64_t) vg->extent_size);
offset = sector - ((grub_uint64_t) seg->start_extent
* (grub_uint64_t) vg->extent_size) + seg_offset;
}
else
{
/* This is a striped segment. We have to find the right PV
similar to RAID0. */
struct grub_lvm_node *stripe = seg->nodes;
grub_uint32_t a, b;
grub_uint64_t seg_offset; /* Offset of the segment in PV device. */
unsigned int stripenr;
offset = sector - ((grub_uint64_t) seg->start_extent
* (grub_uint64_t) vg->extent_size);
a = grub_divmod64 (offset, seg->stripe_size, NULL);
grub_divmod64 (a, seg->node_count, &stripenr);
a = grub_divmod64 (offset, seg->stripe_size * seg->node_count, NULL);
grub_divmod64 (offset, seg->stripe_size, &b);
offset = a * seg->stripe_size + b;
stripe += stripenr;
node = stripe;
seg_offset = ((grub_uint64_t) stripe->start
* (grub_uint64_t) vg->extent_size);
offset += seg_offset;
}
return read_node (node, offset, size, buf);
case GRUB_LVM_MIRROR:
i = 0;
while (1)
{
err = read_node (&seg->nodes[i], sector, size, buf);
if (!err)
return err;
if (++i >= seg->node_count)
return err;
grub_errno = GRUB_ERR_NONE;
}
}
return grub_error (GRUB_ERR_IO, "unknown LVM segment");
}
static grub_err_t
grub_lvm_read (grub_disk_t disk, grub_disk_addr_t sector,
grub_size_t size, char *buf)
{
return read_lv (disk->data, sector, size, buf);
}
static grub_err_t
grub_lvm_write (grub_disk_t disk __attribute ((unused)),
grub_disk_addr_t sector __attribute ((unused)),
grub_size_t size __attribute ((unused)),
const char *buf __attribute ((unused)))
{
return GRUB_ERR_NOT_IMPLEMENTED_YET;
}
static int
grub_lvm_scan_device (const char *name)
{
grub_err_t err;
grub_disk_t disk;
grub_uint64_t mda_offset, mda_size;
char buf[GRUB_LVM_LABEL_SIZE];
char vg_id[GRUB_LVM_ID_STRLEN+1];
char pv_id[GRUB_LVM_ID_STRLEN+1];
char *metadatabuf, *p, *q, *vgname;
struct grub_lvm_label_header *lh = (struct grub_lvm_label_header *) buf;
struct grub_lvm_pv_header *pvh;
struct grub_lvm_disk_locn *dlocn;
struct grub_lvm_mda_header *mdah;
struct grub_lvm_raw_locn *rlocn;
unsigned int i, j, vgname_len;
struct grub_lvm_vg *vg;
struct grub_lvm_pv *pv;
#ifdef GRUB_UTIL
grub_util_info ("scanning %s for LVM", name);
#endif
disk = grub_disk_open (name);
if (!disk)
{
if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
grub_errno = GRUB_ERR_NONE;
return 0;
}
/* Search for label. */
for (i = 0; i < GRUB_LVM_LABEL_SCAN_SECTORS; i++)
{
err = grub_disk_read (disk, i, 0, sizeof(buf), buf);
if (err)
goto fail;
if ((! grub_strncmp ((char *)lh->id, GRUB_LVM_LABEL_ID,
sizeof (lh->id)))
&& (! grub_strncmp ((char *)lh->type, GRUB_LVM_LVM2_LABEL,
sizeof (lh->type))))
break;
}
/* Return if we didn't find a label. */
if (i == GRUB_LVM_LABEL_SCAN_SECTORS)
{
#ifdef GRUB_UTIL
grub_util_info ("no LVM signature found");
#endif
goto fail;
}
pvh = (struct grub_lvm_pv_header *) (buf + grub_le_to_cpu32(lh->offset_xl));
for (i = 0, j = 0; i < GRUB_LVM_ID_LEN; i++)
{
pv_id[j++] = pvh->pv_uuid[i];
if ((i != 1) && (i != 29) && (i % 4 == 1))
pv_id[j++] = '-';
}
pv_id[j] = '\0';
dlocn = pvh->disk_areas_xl;
dlocn++;
/* Is it possible to have multiple data/metadata areas? I haven't
seen devices that have it. */
if (dlocn->offset)
{
grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
"we don't support multiple LVM data areas");
#ifdef GRUB_UTIL
grub_util_info ("we don't support multiple LVM data areas\n");
#endif
goto fail;
}
dlocn++;
mda_offset = grub_le_to_cpu64 (dlocn->offset);
mda_size = grub_le_to_cpu64 (dlocn->size);
/* It's possible to have multiple copies of metadata areas, we just use the
first one. */
/* Allocate buffer space for the circular worst-case scenario. */
metadatabuf = grub_malloc (2 * mda_size);
if (! metadatabuf)
goto fail;
err = grub_disk_read (disk, 0, mda_offset, mda_size, metadatabuf);
if (err)
goto fail2;
mdah = (struct grub_lvm_mda_header *) metadatabuf;
if ((grub_strncmp ((char *)mdah->magic, GRUB_LVM_FMTT_MAGIC,
sizeof (mdah->magic)))
|| (grub_le_to_cpu32 (mdah->version) != GRUB_LVM_FMTT_VERSION))
{
grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
"unknown LVM metadata header");
#ifdef GRUB_UTIL
grub_util_info ("unknown LVM metadata header\n");
#endif
goto fail2;
}
rlocn = mdah->raw_locns;
if (grub_le_to_cpu64 (rlocn->offset) + grub_le_to_cpu64 (rlocn->size) >
grub_le_to_cpu64 (mdah->size))
{
/* Metadata is circular. Copy the wrap in place. */
grub_memcpy (metadatabuf + mda_size,
metadatabuf + GRUB_LVM_MDA_HEADER_SIZE,
grub_le_to_cpu64 (rlocn->offset) +
grub_le_to_cpu64 (rlocn->size) -
grub_le_to_cpu64 (mdah->size));
}
p = q = metadatabuf + grub_le_to_cpu64 (rlocn->offset);
while (*q != ' ' && q < metadatabuf + mda_size)
q++;
if (q == metadatabuf + mda_size)
{
#ifdef GRUB_UTIL
grub_util_info ("error parsing metadata\n");
#endif
goto fail2;
}
vgname_len = q - p;
vgname = grub_malloc (vgname_len + 1);
if (!vgname)
goto fail2;
grub_memcpy (vgname, p, vgname_len);
vgname[vgname_len] = '\0';
p = grub_strstr (q, "id = \"");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("couldn't find ID\n");
#endif
goto fail3;
}
p += sizeof ("id = \"") - 1;
grub_memcpy (vg_id, p, GRUB_LVM_ID_STRLEN);
vg_id[GRUB_LVM_ID_STRLEN] = '\0';
for (vg = vg_list; vg; vg = vg->next)
{
if (! grub_memcmp(vg_id, vg->id, GRUB_LVM_ID_STRLEN))
break;
}
if (! vg)
{
/* First time we see this volume group. We've to create the
whole volume group structure. */
vg = grub_malloc (sizeof (*vg));
if (! vg)
goto fail3;
vg->name = vgname;
grub_memcpy (vg->id, vg_id, GRUB_LVM_ID_STRLEN+1);
vg->extent_size = grub_lvm_getvalue (&p, "extent_size = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown extent size\n");
#endif
goto fail4;
}
vg->lvs = NULL;
vg->pvs = NULL;
p = grub_strstr (p, "physical_volumes {");
if (p)
{
p += sizeof ("physical_volumes {") - 1;
/* Add all the pvs to the volume group. */
while (1)
{
int s;
while (grub_isspace (*p))
p++;
if (*p == '}')
break;
pv = grub_malloc (sizeof (*pv));
q = p;
while (*q != ' ')
q++;
s = q - p;
pv->name = grub_malloc (s + 1);
grub_memcpy (pv->name, p, s);
pv->name[s] = '\0';
p = grub_strstr (p, "id = \"");
if (p == NULL)
goto pvs_fail;
p += sizeof("id = \"") - 1;
grub_memcpy (pv->id, p, GRUB_LVM_ID_STRLEN);
pv->id[GRUB_LVM_ID_STRLEN] = '\0';
pv->start = grub_lvm_getvalue (&p, "pe_start = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown pe_start\n");
#endif
goto pvs_fail;
}
p = grub_strchr (p, '}');
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("error parsing pe_start\n");
#endif
goto pvs_fail;
}
p++;
pv->disk = NULL;
pv->next = vg->pvs;
vg->pvs = pv;
continue;
pvs_fail:
grub_free (pv->name);
grub_free (pv);
goto fail4;
}
}
p = grub_strstr (p, "logical_volumes");
if (p)
{
p += 18;
/* And add all the lvs to the volume group. */
while (1)
{
int s;
int skip_lv = 0;
struct grub_lvm_lv *lv;
struct grub_lvm_segment *seg;
int is_pvmove;
while (grub_isspace (*p))
p++;
if (*p == '}')
break;
lv = grub_malloc (sizeof (*lv));
q = p;
while (*q != ' ')
q++;
s = q - p;
lv->name = grub_malloc (vgname_len + 1 + s + 1);
grub_memcpy (lv->name, vgname, vgname_len);
lv->name[vgname_len] = '-';
grub_memcpy (lv->name + vgname_len + 1, p, s);
lv->name[vgname_len + 1 + s] = '\0';
lv->size = 0;
lv->visible = grub_lvm_check_flag (p, "status", "VISIBLE");
is_pvmove = grub_lvm_check_flag (p, "status", "PVMOVE");
lv->segment_count = grub_lvm_getvalue (&p, "segment_count = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown segment_count\n");
#endif
goto lvs_fail;
}
lv->segments = grub_malloc (sizeof (*seg) * lv->segment_count);
seg = lv->segments;
for (i = 0; i < lv->segment_count; i++)
{
p = grub_strstr (p, "segment");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown segment\n");
#endif
goto lvs_segment_fail;
}
seg->start_extent = grub_lvm_getvalue (&p, "start_extent = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown start_extent\n");
#endif
goto lvs_segment_fail;
}
seg->extent_count = grub_lvm_getvalue (&p, "extent_count = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown extent_count\n");
#endif
goto lvs_segment_fail;
}
p = grub_strstr (p, "type = \"");
if (p == NULL)
goto lvs_segment_fail;
p += sizeof("type = \"") - 1;
lv->size += seg->extent_count * vg->extent_size;
if (grub_memcmp (p, "striped\"",
sizeof ("striped\"") - 1) == 0)
{
struct grub_lvm_node *stripe;
seg->type = GRUB_LVM_STRIPED;
seg->node_count = grub_lvm_getvalue (&p, "stripe_count = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown stripe_count\n");
#endif
goto lvs_segment_fail;
}
if (seg->node_count != 1)
seg->stripe_size = grub_lvm_getvalue (&p, "stripe_size = ");
seg->nodes = grub_zalloc (sizeof (*stripe)
* seg->node_count);
stripe = seg->nodes;
p = grub_strstr (p, "stripes = [");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown stripes\n");
#endif
goto lvs_segment_fail2;
}
p += sizeof("stripes = [") - 1;
for (j = 0; j < seg->node_count; j++)
{
p = grub_strchr (p, '"');
if (p == NULL)
continue;
q = ++p;
while (*q != '"')
q++;
s = q - p;
stripe->name = grub_malloc (s + 1);
if (stripe->name == NULL)
goto lvs_segment_fail2;
grub_memcpy (stripe->name, p, s);
stripe->name[s] = '\0';
stripe->start = grub_lvm_getvalue (&p, ",");
if (p == NULL)
continue;
stripe++;
}
}
else if (grub_memcmp (p, "mirror\"", sizeof ("mirror\"") - 1)
== 0)
{
seg->type = GRUB_LVM_MIRROR;
seg->node_count = grub_lvm_getvalue (&p, "mirror_count = ");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown mirror_count\n");
#endif
goto lvs_segment_fail;
}
seg->nodes = grub_zalloc (sizeof (seg->nodes[0])
* seg->node_count);
p = grub_strstr (p, "mirrors = [");
if (p == NULL)
{
#ifdef GRUB_UTIL
grub_util_info ("unknown mirrors\n");
#endif
goto lvs_segment_fail2;
}
p += sizeof("mirrors = [") - 1;
for (j = 0; j < seg->node_count; j++)
{
char *lvname;
p = grub_strchr (p, '"');
if (p == NULL)
continue;
q = ++p;
while (*q != '"')
q++;
s = q - p;
lvname = grub_malloc (s + 1);
if (lvname == NULL)
goto lvs_segment_fail2;
grub_memcpy (lvname, p, s);
lvname[s] = '\0';
seg->nodes[j].name = lvname;
p = q + 1;
}
/* Only first (original) is ok with in progress pvmove. */
if (is_pvmove)
seg->node_count = 1;
}
else
{
#ifdef GRUB_UTIL
char *p2;
p2 = grub_strchr (p, '"');
if (p2)
*p2 = 0;
grub_util_info ("unknown LVM type %s\n", p);
if (p2)
*p2 ='"';
#endif
/* Found a non-supported type, give up and move on. */
skip_lv = 1;
break;
}
seg++;
continue;
lvs_segment_fail2:
grub_free (seg->nodes);
lvs_segment_fail:
goto fail4;
}
if (p != NULL)
p = grub_strchr (p, '}');
if (p == NULL)
goto lvs_fail;
p += 3;
if (skip_lv)
{
grub_free (lv->name);
grub_free (lv);
continue;
}
lv->number = lv_count++;
lv->vg = vg;
lv->next = vg->lvs;
vg->lvs = lv;
continue;
lvs_fail:
grub_free (lv->name);
grub_free (lv);
goto fail4;
}
}
/* Match lvs. */
{
struct grub_lvm_lv *lv1;
struct grub_lvm_lv *lv2;
for (lv1 = vg->lvs; lv1; lv1 = lv1->next)
for (i = 0; i < lv1->segment_count; i++)
for (j = 0; j < lv1->segments[i].node_count; j++)
{
if (vg->pvs)
for (pv = vg->pvs; pv; pv = pv->next)
{
if (! grub_strcmp (pv->name,
lv1->segments[i].nodes[j].name))
{
lv1->segments[i].nodes[j].pv = pv;
break;
}
}
if (lv1->segments[i].nodes[j].pv == NULL)
for (lv2 = vg->lvs; lv2; lv2 = lv2->next)
if (grub_strcmp (lv2->name + grub_strlen (vg->name) + 1,
lv1->segments[i].nodes[j].name) == 0)
lv1->segments[i].nodes[j].lv = lv2;
}
}
vg->next = vg_list;
vg_list = vg;
}
else
{
grub_free (vgname);
}
/* Match the device we are currently reading from with the right
PV. */
if (vg->pvs)
for (pv = vg->pvs; pv; pv = pv->next)
{
if (! grub_memcmp (pv->id, pv_id, GRUB_LVM_ID_STRLEN))
{
/* This could happen to LVM on RAID, pv->disk points to the
raid device, we shouldn't change it. */
if (! pv->disk)
pv->disk = grub_disk_open (name);
break;
}
}
goto fail2;
/* Failure path. */
fail4:
grub_free (vg);
fail3:
grub_free (vgname);
/* Normal exit path. */
fail2:
grub_free (metadatabuf);
fail:
grub_disk_close (disk);
if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
grub_errno = GRUB_ERR_NONE;
grub_print_error ();
return 0;
}
static struct grub_disk_dev grub_lvm_dev =
{
.name = "lvm",
.id = GRUB_DISK_DEVICE_LVM_ID,
.iterate = grub_lvm_iterate,
.open = grub_lvm_open,
.close = grub_lvm_close,
.read = grub_lvm_read,
.write = grub_lvm_write,
#ifdef GRUB_UTIL
.memberlist = grub_lvm_memberlist,
#endif
.next = 0
};
GRUB_MOD_INIT(lvm)
{
grub_device_iterate (&grub_lvm_scan_device);
if (grub_errno)
{
grub_print_error ();
grub_errno = GRUB_ERR_NONE;
}
grub_disk_dev_register (&grub_lvm_dev);
}
GRUB_MOD_FINI(lvm)
{
grub_disk_dev_unregister (&grub_lvm_dev);
vg_list = NULL;
/* FIXME: free the lvm list. */
}
Reference in New Issue View Git Blame Copy Permalink