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lvm2/lib/label/label.c
Zdenek Kabelac 39b7d1ba8f cleanup: typos in comments 
Collection of typos in code comments.
Should have no runtime effect.
2024-08-30 16:51:15 +02:00

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/*
* Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "lib/misc/lib.h"
#include "base/memory/zalloc.h"
#include "lib/label/label.h"
#include "lib/misc/crc.h"
#include "lib/mm/xlate.h"
#include "lib/cache/lvmcache.h"
#include "lib/device/bcache.h"
#include "lib/commands/toolcontext.h"
#include "lib/activate/activate.h"
#include "lib/label/hints.h"
#include "lib/metadata/metadata.h"
#include "lib/format_text/layout.h"
#include "lib/device/device_id.h"
#include "lib/device/online.h"
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/resource.h>
/* FIXME Allow for larger labels? Restricted to single sector currently */
static uint64_t _current_bcache_size_bytes;
/*
* Internal labeller struct.
*/
struct labeller_i {
struct dm_list list;
struct labeller *l;
char name[0];
};
static struct dm_list _labellers;
static struct labeller_i *_alloc_li(const char *name, struct labeller *l)
{
struct labeller_i *li;
size_t len;
len = strlen(name);
if (!(li = malloc(sizeof(*li) + len + 1))) {
log_error("Couldn't allocate memory for labeller list object.");
return NULL;
}
li->l = l;
memcpy(li->name, name, len + 1);
return li;
}
int label_init(void)
{
dm_list_init(&_labellers);
return 1;
}
void label_exit(void)
{
struct labeller_i *li, *tli;
dm_list_iterate_items_safe(li, tli, &_labellers) {
dm_list_del(&li->list);
li->l->ops->destroy(li->l);
free(li);
}
dm_list_init(&_labellers);
}
int label_register_handler(struct labeller *handler)
{
struct labeller_i *li;
if (!(li = _alloc_li(handler->fmt->name, handler)))
return_0;
dm_list_add(&_labellers, &li->list);
return 1;
}
struct labeller *label_get_handler(const char *name)
{
struct labeller_i *li;
dm_list_iterate_items(li, &_labellers)
if (!strcmp(li->name, name))
return li->l;
return NULL;
}
/* FIXME Also wipe associated metadata area headers? */
int label_remove(struct device *dev)
{
char readbuf[LABEL_SIZE] __attribute__((aligned(8)));
int r = 1;
uint64_t sector;
int wipe;
struct labeller_i *li;
struct label_header *lh;
struct lvmcache_info *info;
log_very_verbose("Scanning for labels to wipe from %s", dev_name(dev));
if (!label_scan_open_excl(dev)) {
log_error("Failed to open device %s", dev_name(dev));
return 0;
}
/* Scan first few sectors for anything looking like a label */
for (sector = 0; sector < LABEL_SCAN_SECTORS;
sector += LABEL_SIZE >> SECTOR_SHIFT) {
memset(readbuf, 0, sizeof(readbuf));
if (!dev_read_bytes(dev, sector << SECTOR_SHIFT, LABEL_SIZE, readbuf)) {
log_error("Failed to read label from %s sector %llu",
dev_name(dev), (unsigned long long)sector);
continue;
}
lh = (struct label_header *)readbuf;
wipe = 0;
if (!memcmp(lh->id, LABEL_ID, sizeof(lh->id))) {
if (xlate64(lh->sector_xl) == sector)
wipe = 1;
} else {
dm_list_iterate_items(li, &_labellers) {
if (li->l->ops->can_handle(li->l, (char *)lh, sector)) {
wipe = 1;
break;
}
}
}
if (wipe) {
log_very_verbose("%s: Wiping label at sector %llu",
dev_name(dev), (unsigned long long)sector);
if (!dev_write_zeros(dev, sector << SECTOR_SHIFT, LABEL_SIZE)) {
log_error("Failed to remove label from %s at sector %llu",
dev_name(dev), (unsigned long long)sector);
r = 0;
} else {
/* Also remove the PV record from cache. */
info = lvmcache_info_from_pvid(dev->pvid, dev, 0);
if (info)
lvmcache_del(info);
}
}
}
return r;
}
/* Caller may need to use label_get_handler to create label struct! */
int label_write(struct device *dev, struct label *label)
{
char buf[LABEL_SIZE] __attribute__((aligned(8)));
struct label_header *lh = (struct label_header *) buf;
uint64_t offset;
int r = 1;
if (!label->labeller->ops->write) {
log_error("Label handler does not support label writes");
return 0;
}
if ((LABEL_SIZE + (label->sector << SECTOR_SHIFT)) > LABEL_SCAN_SIZE) {
log_error("Label sector %" PRIu64 " beyond range (%ld)",
label->sector, LABEL_SCAN_SECTORS);
return 0;
}
memset(buf, 0, LABEL_SIZE);
memcpy(lh->id, LABEL_ID, sizeof(lh->id));
lh->sector_xl = xlate64(label->sector);
lh->offset_xl = xlate32(sizeof(*lh));
if (!(label->labeller->ops->write)(label, buf))
return_0;
lh->crc_xl = xlate32(calc_crc(INITIAL_CRC, (uint8_t *)&lh->offset_xl, LABEL_SIZE -
((uint8_t *) &lh->offset_xl - (uint8_t *) lh)));
log_very_verbose("%s: Writing label to sector %" PRIu64 " with stored offset %"
PRIu32 ".", dev_name(dev), label->sector,
xlate32(lh->offset_xl));
if (!label_scan_open(dev)) {
log_error("Failed to open device %s", dev_name(dev));
return 0;
}
offset = label->sector << SECTOR_SHIFT;
dev_set_last_byte(dev, offset + LABEL_SIZE);
if (!dev_write_bytes(dev, offset, LABEL_SIZE, buf)) {
log_debug_devs("Failed to write label to %s", dev_name(dev));
return 0;
}
dev_unset_last_byte(dev);
return r;
}
void label_destroy(struct label *label)
{
label->labeller->ops->destroy_label(label->labeller, label);
free(label);
}
struct label *label_create(struct labeller *labeller)
{
struct label *label;
if (!(label = zalloc(sizeof(*label)))) {
log_error("label allocation failed");
return NULL;
}
label->labeller = labeller;
labeller->ops->initialise_label(labeller, label);
return label;
}
/* global variable for accessing the bcache populated by label scan */
/* FIXME/TODO convert to cmd_context */
static struct bcache *scan_bcache;
#define BCACHE_BLOCK_SIZE_IN_SECTORS 256 /* 256*512 = 128K */
static bool _in_bcache(struct device *dev)
{
if (!dev)
return NULL;
return (dev->flags & DEV_IN_BCACHE) ? true : false;
}
static struct labeller *_find_lvm_header(struct device *dev,
char *headers_buf,
size_t headers_buf_size,
uint64_t *label_sector,
uint64_t block_sector,
uint64_t start_sector)
{
struct labeller_i *li;
struct labeller *labeller_ret = NULL;
struct label_header *lh;
uint64_t sector;
int found = 0;
for (sector = start_sector; sector < start_sector + LABEL_SCAN_SECTORS;
sector += LABEL_SIZE >> SECTOR_SHIFT) {
if ((sector * 512) >= headers_buf_size)
break;
lh = (struct label_header *) (headers_buf + (sector << SECTOR_SHIFT));
if (!memcmp(lh->id, LABEL_ID, sizeof(lh->id))) {
if (found) {
log_error("Ignoring additional label on %s at sector %llu",
dev_name(dev), (unsigned long long)(block_sector + sector));
}
if (xlate64(lh->sector_xl) != sector) {
log_warn("%s: Label for sector %llu found at sector %llu - ignoring.",
dev_name(dev),
(unsigned long long)xlate64(lh->sector_xl),
(unsigned long long)(block_sector + sector));
continue;
}
if (calc_crc(INITIAL_CRC, (uint8_t *)&lh->offset_xl,
LABEL_SIZE - ((uint8_t *) &lh->offset_xl - (uint8_t *) lh)) != xlate32(lh->crc_xl)) {
log_very_verbose("Label checksum incorrect on %s - ignoring", dev_name(dev));
continue;
}
if (found)
continue;
}
dm_list_iterate_items(li, &_labellers) {
if (li->l->ops->can_handle(li->l, (char *) lh, block_sector + sector)) {
log_debug("Found label at sector %llu on %s",
(unsigned long long)(block_sector + sector), dev_name(dev));
if (found) {
log_error("Ignoring additional label on %s at sector %llu",
dev_name(dev),
(unsigned long long)(block_sector + sector));
continue;
}
labeller_ret = li->l;
found = 1;
if (label_sector)
*label_sector = block_sector + sector;
break;
}
}
}
return labeller_ret;
}
/*
* Process/parse the headers from the data read from a device.
* Populates lvmcache with device / mda locations / vgname
* so that vg_read(vgname) will know which devices/locations
* to read metadata from.
*
* If during processing, headers/metadata are found to be needed
* beyond the range of the scanned block, then additional reads
* are performed in the processing functions to get that data.
*/
static int _process_block(struct cmd_context *cmd, struct dev_filter *f,
struct device *dev, char *headers_buf, size_t headers_buf_size,
uint64_t block_sector, uint64_t start_sector,
int *is_lvm_device)
{
char *label_buf;
struct labeller *labeller;
uint64_t label_sector = 0;
int is_duplicate = 0;
int ret = 0;
dev->flags &= ~DEV_SCAN_FOUND_LABEL;
/*
* The device may have signatures that exclude it from being processed,
* even if it might look like a PV. Now that the device has been read
* and data is available in bcache for it, recheck filters, including
* those that use data. The device needs to be excluded before it
* begins to be processed as a PV.
*/
if (f) {
if (!f->passes_filter(cmd, f, dev, NULL)) {
/*
* If this device was previously scanned (not common)
* and if it passed filters at that point, lvmcache
* info may have been saved for it. Now the same
* device is being scanned again, and it may fail
* filters this time. If the caller did not clear
* lvmcache info for this dev before rescanning, do
* that now. It's unlikely this is actually needed.
*/
if (dev->pvid[0]) {
log_print_unless_silent("Clear pvid and info for filtered dev %s.", dev_name(dev));
lvmcache_del_dev(dev);
memset(dev->pvid, 0, sizeof(dev->pvid));
}
*is_lvm_device = 0;
goto_out;
}
}
/*
* Finds the data sector containing the label.
*/
if (!(labeller = _find_lvm_header(dev, headers_buf, headers_buf_size, &label_sector, block_sector, start_sector))) {
/*
* Non-PVs exit here
*
* FIXME: check for PVs with errors that also exit here!
* i.e. this code cannot distinguish between a non-lvm
* device an an lvm device with errors.
*/
log_very_verbose("%s: No lvm label detected", dev_name(dev));
/* See comment above */
if (dev->pvid[0]) {
log_print_unless_silent("Clear pvid and info for no lvm header %s", dev_name(dev));
lvmcache_del_dev(dev);
memset(dev->pvid, 0, sizeof(dev->pvid));
}
dev->flags |= DEV_SCAN_FOUND_NOLABEL;
*is_lvm_device = 0;
goto out;
}
dev->flags |= DEV_SCAN_FOUND_LABEL;
*is_lvm_device = 1;
label_buf = headers_buf + (label_sector * 512);
/*
* This is the point where the scanning code dives into the rest of
* lvm. ops->read() is _text_read() which reads the pv_header, mda
* locations, and metadata text. All of the info it finds about the PV
* and VG is stashed in lvmcache which saves it in the form of
* info/vginfo structs. That lvmcache info is used later when the
* command wants to read the VG to do something to it.
*/
ret = labeller->ops->read(cmd, labeller, dev, label_buf, label_sector, &is_duplicate);
if (!ret) {
if (is_duplicate) {
/*
* _text_read() called lvmcache_add() which found an
* existing info struct for this PVID but for a
* different dev. lvmcache_add() did not add an info
* struct for this dev, but added this dev to the list
* of duplicate devs.
*/
log_debug("label scan found duplicate PVID %s on %s", dev->pvid, dev_name(dev));
} else {
/*
* Leave the info in lvmcache because the device is
* present and can still be used even if it has
* metadata that we can't process (we can get metadata
* from another PV/mda.) _text_read only saves mdas
* with good metadata in lvmcache (this includes old
* metadata), and if a PV has no mdas with good
* metadata, then the info for the PV will be in
* lvmcache with empty info->mdas, and it will behave
* like a PV with no mdas (a common configuration.)
*/
log_warn("WARNING: scan failed to get metadata summary from %s PVID %s", dev_name(dev), dev->pvid);
}
}
out:
return ret;
}
static int _scan_dev_open(struct device *dev)
{
struct dm_list *name_list;
struct dm_str_list *name_sl;
const char *name;
const char *modestr;
struct stat sbuf;
int flags = 0;
int fd, di;
if (!dev)
return 0;
if (dev->flags & DEV_IN_BCACHE) {
/* Shouldn't happen */
log_error("Device open %s has DEV_IN_BCACHE already set", dev_name(dev));
dev->flags &= ~DEV_IN_BCACHE;
}
if (dev->bcache_di != -1) {
/* Shouldn't happen */
log_error("Device open %s already open with di %d fd %d",
dev_name(dev), dev->bcache_di, dev->bcache_fd);
return 0;
}
next_name:
/*
* All the names for this device (major:minor) are kept on
* dev->aliases, the first one is the primary/preferred name.
*
* The default name preferences in dev-cache mean that the first
* name in dev->aliases is not a symlink for scsi devices, but is
* the /dev/mapper/ symlink for mpath devices.
*
* If preferred names are set to symlinks, should this
* first attempt to open using a non-symlink?
*
* dm_list_first() returns NULL if the list is empty.
*/
if (!(name_list = dm_list_first(&dev->aliases))) {
log_error("Device open %u:%u has no path names.",
MAJOR(dev->dev), MINOR(dev->dev));
return 0;
}
name_sl = dm_list_item(name_list, struct dm_str_list);
name = name_sl->str;
flags |= O_DIRECT;
flags |= O_NOATIME;
/*
* FIXME: udev is a train wreck when we open RDWR and close, so we
* need to only use RDWR when we actually need to write, and use
* RDONLY otherwise. Fix, disable or scrap udev nonsense so we can
* just open with RDWR by default.
*/
if (dev->flags & DEV_BCACHE_EXCL) {
flags |= O_EXCL;
flags |= O_RDWR;
modestr = "rwex";
} else if (dev->flags & DEV_BCACHE_WRITE) {
flags |= O_RDWR;
modestr = "rw";
} else {
flags |= O_RDONLY;
modestr = "ro";
}
fd = open(name, flags, 0777);
if (fd < 0) {
if ((errno == EBUSY) && (flags & O_EXCL)) {
log_error("Can't open %s exclusively. Mounted filesystem?",
dev_name(dev));
return 0;
} else {
/*
* drop name from dev->aliases and use verify_aliases to
* drop any other invalid aliases before retrying open with
* any remaining valid paths.
*/
log_debug("Drop alias for %u:%u failed open %s (%d).",
MAJOR(dev->dev), MINOR(dev->dev), name, errno);
dev_cache_failed_path(dev, name);
dev_cache_verify_aliases(dev);
goto next_name;
}
}
/* Verify that major:minor from the path still match dev. */
if ((fstat(fd, &sbuf) < 0) || (sbuf.st_rdev != dev->dev)) {
log_warn("Invalid path %s for device %u:%u, trying different path.",
name, MAJOR(dev->dev), MINOR(dev->dev));
(void)close(fd);
dev_cache_failed_path(dev, name);
dev_cache_verify_aliases(dev);
goto next_name;
}
dev->flags |= DEV_IN_BCACHE;
dev->bcache_fd = fd;
di = bcache_set_fd(fd);
if (di == -1) {
log_error("Failed to set bcache fd.");
if (close(fd))
log_sys_debug("close", name);
dev->bcache_fd = -1;
return 0;
}
log_debug("open %s %s di %d fd %d", dev_name(dev), modestr, di, fd);
dev->bcache_di = di;
return 1;
}
static int _scan_dev_close(struct device *dev)
{
if (!(dev->flags & DEV_IN_BCACHE))
log_error("scan_dev_close %s no DEV_IN_BCACHE set", dev_name(dev));
dev->flags &= ~DEV_IN_BCACHE;
dev->flags &= ~DEV_BCACHE_EXCL;
dev->flags &= ~DEV_BCACHE_WRITE;
if (dev->bcache_di == -1) {
log_error("scan_dev_close %s already closed", dev_name(dev));
return 0;
}
bcache_clear_fd(dev->bcache_di);
if (close(dev->bcache_fd))
log_warn("close %s errno %d", dev_name(dev), errno);
dev->bcache_fd = -1;
dev->bcache_di = -1;
return 1;
}
// Like bcache_invalidate, only it throws any dirty data away if the
// write fails.
static void _invalidate_di(struct bcache *cache, int di)
{
if (!bcache_invalidate_di(cache, di))
bcache_abort_di(cache, di);
}
/*
* Read or reread label/metadata from selected devs.
*
* Reads and looks at label_header, pv_header, pv_header_extension,
* mda_header, raw_locns, vg metadata from each device.
*
* Effect is populating lvmcache with latest info/vginfo (PV/VG) data
* from the devs. If a scanned device does not have a label_header,
* its info is removed from lvmcache.
*/
#define HEADERS_BUF_SIZE 4096
static int _scan_list(struct cmd_context *cmd, struct dev_filter *f,
struct dm_list *devs, int want_other_devs, int *failed)
{
char headers_buf[HEADERS_BUF_SIZE];
struct dm_list wait_devs;
struct dm_list done_devs;
struct device_list *devl, *devl2;
struct block *bb;
int scan_read_errors = 0;
int scan_process_errors = 0;
int scan_failed_count = 0;
int rem_prefetches;
int submit_count;
int is_lvm_device;
int ret;
dm_list_init(&wait_devs);
dm_list_init(&done_devs);
log_debug_devs("Scanning %d devices for VG info", dm_list_size(devs));
scan_more:
rem_prefetches = bcache_max_prefetches(scan_bcache);
submit_count = 0;
dm_list_iterate_items_safe(devl, devl2, devs) {
devl->dev->flags &= ~DEV_SCAN_NOT_READ;
/*
* If we prefetch more devs than blocks in the cache, then the
* cache will wait for earlier reads to complete, toss the
* results, and reuse those blocks before we've had a chance to
* use them. So, prefetch as many as are available, wait for
* and process them, then repeat.
*/
if (!rem_prefetches)
break;
if (!_in_bcache(devl->dev)) {
if (!_scan_dev_open(devl->dev)) {
log_debug_devs("Scan failed to open %u:%u %s.",
MAJOR(devl->dev->dev), MINOR(devl->dev->dev), dev_name(devl->dev));
dm_list_del(&devl->list);
devl->dev->flags |= DEV_SCAN_NOT_READ;
continue;
}
}
bcache_prefetch(scan_bcache, devl->dev->bcache_di, 0);
rem_prefetches--;
submit_count++;
dm_list_del(&devl->list);
dm_list_add(&wait_devs, &devl->list);
}
log_debug_devs("Scanning submitted %d reads", submit_count);
dm_list_iterate_items_safe(devl, devl2, &wait_devs) {
bb = NULL;
is_lvm_device = 0;
if (!bcache_get(scan_bcache, devl->dev->bcache_di, 0, 0, &bb)) {
log_debug_devs("Scan failed to read %s.", dev_name(devl->dev));
scan_read_errors++;
scan_failed_count++;
devl->dev->flags |= DEV_SCAN_NOT_READ;
lvmcache_del_dev(devl->dev);
if (bb)
bcache_put(bb);
} else {
/* copy the first 4k from bb that will contain label_header */
memcpy(headers_buf, bb->data, HEADERS_BUF_SIZE);
/*
* "put" the bcache block before process_block because
* processing metadata may need to invalidate and reread
* metadata that's covered by bb. invalidate/reread is
* not allowed while bb is held. The functions for
* filtering and scanning metadata for this device use
* dev_read_bytes(), which will generally grab the
* bcache block/data that we're putting here. Since
* we're doing put, it's possible but not likely that
* bcache could drop the block before dev_read_bytes()
* uses it again, in which case bcache will reread it
* from disk for dev_read_bytes().
*/
bcache_put(bb);
log_debug_devs("Processing data from device %s %u:%u di %d.",
dev_name(devl->dev),
MAJOR(devl->dev->dev), MINOR(devl->dev->dev),
devl->dev->bcache_di);
ret = _process_block(cmd, f, devl->dev, headers_buf, sizeof(headers_buf), 0, 0, &is_lvm_device);
if (!ret && is_lvm_device) {
log_debug_devs("Scan failed to process %s", dev_name(devl->dev));
scan_process_errors++;
scan_failed_count++;
}
}
/*
* Keep the bcache block of lvm devices we have processed so
* that the vg_read phase can reuse it. If bcache failed to
* read the block, or the device does not belong to lvm, then
* drop it from bcache. When "want_other_devs" is set, it
* means the caller wants to scan and keep open non-lvm devs,
* e.g. to pvcreate them.
*/
if (!is_lvm_device && !want_other_devs) {
_invalidate_di(scan_bcache, devl->dev->bcache_di);
_scan_dev_close(devl->dev);
}
dm_list_del(&devl->list);
dm_list_add(&done_devs, &devl->list);
}
if (!dm_list_empty(devs))
goto scan_more;
log_debug_devs("Scanned devices: read errors %d process errors %d failed %d",
scan_read_errors, scan_process_errors, scan_failed_count);
if (failed)
*failed = scan_failed_count;
dm_list_splice(devs, &done_devs);
return 1;
}
/*
* We don't know ahead of time if we will find some VG metadata
* that is larger than the total size of the bcache, which would
* prevent us from reading/writing the VG since we do not dynamically
* increase the bcache size when we find it's too small. In these
* cases the user would need to set io_memory_size to be larger
* than the max VG metadata size (lvm does not impose any limit on
* the metadata size.)
*/
#define MIN_BCACHE_BLOCKS 32 /* 4MB (32 * 128KB) */
#define MAX_BCACHE_BLOCKS 4096 /* 512MB (4096 * 128KB) */
int label_scan_setup_bcache(void)
{
struct io_engine *ioe = NULL;
int iomem_kb = io_memory_size();
int block_size_kb = (BCACHE_BLOCK_SIZE_IN_SECTORS * 512) / 1024;
int cache_blocks;
if (scan_bcache)
return 1;
cache_blocks = iomem_kb / block_size_kb;
if (cache_blocks < MIN_BCACHE_BLOCKS)
cache_blocks = MIN_BCACHE_BLOCKS;
if (cache_blocks > MAX_BCACHE_BLOCKS)
cache_blocks = MAX_BCACHE_BLOCKS;
_current_bcache_size_bytes = cache_blocks * BCACHE_BLOCK_SIZE_IN_SECTORS * 512;
if (use_aio()) {
if (!(ioe = create_async_io_engine())) {
log_warn("Failed to set up async io, using sync io.");
init_use_aio(0);
}
}
if (!ioe) {
if (!(ioe = create_sync_io_engine())) {
log_error("Failed to set up sync io.");
return 0;
}
}
if (!(scan_bcache = bcache_create(BCACHE_BLOCK_SIZE_IN_SECTORS, cache_blocks, ioe))) {
log_error("Failed to set up io layer with %d blocks.", cache_blocks);
return 0;
}
return 1;
}
/*
* We don't know how many of num_devs will be PVs that we need to
* keep open, but if it's greater than the soft limit, then we'll
* need the soft limit raised, so do that before starting.
*
* If opens approach the raised soft/hard limit while scanning, then
* we could also attempt to raise the soft/hard limits during the scan.
*/
#define BASE_FD_COUNT 32 /* Number of open files we want apart from devs */
void prepare_open_file_limit(struct cmd_context *cmd, unsigned int num_devs)
{
#ifdef HAVE_PRLIMIT
struct rlimit old = { 0 }, new;
unsigned int want = num_devs + BASE_FD_COUNT;
int rv;
rv = prlimit(0, RLIMIT_NOFILE, NULL, &old);
if (rv < 0) {
log_debug("Checking fd limit for num_devs %u failed %d", num_devs, errno);
return;
}
log_debug("Checking fd limit for num_devs %u want %u soft %lld hard %lld",
num_devs, want, (long long)old.rlim_cur, (long long)old.rlim_max);
/* Current soft limit is enough */
if (old.rlim_cur > want)
return;
/* Soft limit already raised to max */
if (old.rlim_cur == old.rlim_max)
return;
/* Raise soft limit up to hard/max limit */
new.rlim_cur = old.rlim_max;
new.rlim_max = old.rlim_max;
log_debug("Setting fd limit for num_devs %u soft %lld hard %lld",
num_devs, (long long)new.rlim_cur, (long long)new.rlim_max);
rv = prlimit(0, RLIMIT_NOFILE, &new, &old);
if (rv < 0) {
if (errno == EPERM)
log_warn("WARNING: permission error setting open file limit for scanning %u devices.", num_devs);
else
log_warn("WARNING: cannot set open file limit for scanning %u devices.", num_devs);
return;
}
#endif
}
/*
* Currently the only caller is pvck which probably doesn't need
* deferred filters checked after the read... it wants to know if
* anything has the pvid, even a dev that might be filtered.
*/
int label_scan_for_pvid(struct cmd_context *cmd, char *pvid, struct device **dev_out)
{
char buf[LABEL_SIZE] __attribute__((aligned(8)));
struct dm_list devs;
struct dev_iter *iter;
struct device *dev;
struct pv_header *pvh;
int ret = 0;
dm_list_init(&devs);
/*
* Creates a list of available devices, does not open or read any,
* and does not filter them.
*/
if (!setup_devices(cmd)) {
log_error("Failed to set up devices.");
return 0;
}
if (!label_scan_setup_bcache())
return_0;
/*
* Iterating over all available devices with cmd->filter filters
* devices; those returned from dev_iter_get are the devs that
* pass filters, and are those we can use.
*/
if (!(iter = dev_iter_create(cmd->filter, 0))) {
log_error("Scanning failed to get devices.");
return 0;
}
log_debug_devs("Reading labels for pvid");
while ((dev = dev_iter_get(cmd, iter))) {
memset(buf, 0, sizeof(buf));
if (!label_scan_open(dev))
continue;
if (!dev_read_bytes(dev, 512, LABEL_SIZE, buf)) {
_scan_dev_close(dev);
goto out;
}
pvh = (struct pv_header *)(buf + 32);
if (!memcmp(pvh->pv_uuid, pvid, ID_LEN)) {
*dev_out = dev;
_scan_dev_close(dev);
break;
}
_scan_dev_close(dev);
}
ret = 1;
out:
dev_iter_destroy(iter);
return ret;
}
/*
* Clear state that label_scan_vg_online() created so it will not
* confuse the standard label_scan() that the caller falls back to.
* the results of filtering (call filter->wipe)
* the results of matching device_id (reset dev and du)
* the results of scanning in lvmcache
*/
static void _clear_scan_state(struct cmd_context *cmd, struct dm_list *devs)
{
struct device_list *devl;
struct device *dev;
struct dev_use *du;
dm_list_iterate_items(devl, devs) {
dev = devl->dev;
cmd->filter->wipe(cmd, cmd->filter, dev, NULL);
dev->flags &= ~DEV_MATCHED_USE_ID;
dev->id = NULL;
if ((du = get_du_for_dev(cmd, dev)))
du->dev = NULL;
lvmcache_del_dev(dev);
memset(dev->pvid, 0, ID_LEN);
}
}
/*
* Use files under /run/lvm/, created by pvscan --cache autoactivation,
* to optimize device setup/scanning. autoactivation happens during
* system startup when the hints file is not useful, but he pvs_online
* files can provide a similar optimization to the hints file.
*/
int label_scan_vg_online(struct cmd_context *cmd, const char *vgname,
int *found_none, int *found_all, int *found_incomplete)
{
struct dm_list pvs_online;
struct dm_list devs;
struct dm_list devs_drop;
struct pv_online *po;
struct device_list *devl, *devl2;
int relax_deviceid_filter = 0;
unsigned metadata_pv_count;
int try_dev_scan = 0;
dm_list_init(&pvs_online);
dm_list_init(&devs);
dm_list_init(&devs_drop);
log_debug_devs("Finding online devices to scan");
/*
* First attempt to use /run/lvm/pvs_lookup/vgname which should be
* used in cases where all PVs in a VG do not contain metadata.
* When the pvs_lookup file does not exist, then simply use all
* /run/lvm/pvs_online/pvid files that contain a matching vgname.
* The list of po structs represents the PVs in the VG, and the
* info from the online files tell us which devices those PVs are
* located on.
*/
if (vgname) {
if (!get_pvs_lookup(&pvs_online, vgname)) {
if (!get_pvs_online(&pvs_online, vgname))
goto bad;
}
} else {
if (!get_pvs_online(&pvs_online, NULL))
goto bad;
}
if (dm_list_empty(&pvs_online)) {
*found_none = 1;
return 1;
}
/*
* For each po add a struct dev to dev-cache. This is a faster
* alternative to the usual dev_cache_scan() which looks at all
* devices. If this optimization fails, then fall back to the usual
* dev_cache_scan().
*/
dm_list_iterate_items(po, &pvs_online) {
if (!(po->dev = setup_dev_in_dev_cache(cmd, po->devno, po->devname[0] ? po->devname : NULL))) {
log_debug("No device found for quick mapping of online PV %u:%u %s PVID %s.",
MAJOR(po->devno), MINOR(po->devno), po->devname, po->pvid);
try_dev_scan = 1;
continue;
}
if (!(devl = dm_pool_zalloc(cmd->mem, sizeof(*devl))))
goto_bad;
devl->dev = po->dev;
dm_list_add(&devs, &devl->list);
}
/*
* Translating a devno (major:minor) into a device name can be
* problematic for some devices that have unusual sysfs layouts, so if
* this happens, do a full dev_cache_scan, which is slower, but is
* sure to find the device.
*/
if (try_dev_scan) {
log_debug("Repeat dev cache scan to translate devnos.");
dev_cache_scan(cmd);
dm_list_iterate_items(po, &pvs_online) {
if (po->dev)
continue;
if (!(po->dev = dev_cache_get_by_devt(cmd, po->devno))) {
log_error("No device found for %u:%u PVID %s.",
MAJOR(po->devno), MINOR(po->devno), po->pvid);
goto bad;
}
if (!(devl = dm_pool_zalloc(cmd->mem, sizeof(*devl))))
goto_bad;
devl->dev = po->dev;
dm_list_add(&devs, &devl->list);
}
}
/*
* factor code common to pvscan_cache_args
*/
/*
* Match devs with the devices file because special/optimized
* device setup was used which does not check the devices file.
* If a match fails here do not exclude it, that will be done below by
* passes_filter() which runs filter-deviceid. The
* relax_deviceid_filter case needs to be able to work around
* unmatching devs.
*/
if (cmd->enable_devices_file) {
dm_list_iterate_items(devl, &devs)
device_ids_match_dev(cmd, devl->dev);
}
if (cmd->enable_devices_list)
device_ids_match_device_list(cmd);
if (cmd->enable_devices_file &&
(device_ids_use_devname(cmd) || cmd->device_ids_refresh_trigger)) {
relax_deviceid_filter = 1;
cmd->filter_deviceid_skip = 1;
/* PVIDs read from devs matched to devices file below instead. */
log_debug("Skipping device_id filtering");
}
/*
* See corresponding code in pvscan. This function is used during
* startup autoactivation when udev has not created all symlinks, so
* regex filter containing symlinks doesn't work. pvscan has code
* to properly check devs against the filter using DEVLINKS. The
* pvscan will only create pvs_online files for devs that pass the
* filter. We get devs from the pvs_online files, so we inherit the
* regex filtering from pvscan and don't have to do it ourself.
*/
cmd->filter_regex_skip = 1;
cmd->filter_nodata_only = 1;
dm_list_iterate_items_safe(devl, devl2, &devs) {
if (!cmd->filter->passes_filter(cmd, cmd->filter, devl->dev, NULL)) {
log_print_unless_silent("%s excluded: %s.",
dev_name(devl->dev), dev_filtered_reason(devl->dev));
dm_list_del(&devl->list);
dm_list_add(&devs_drop, &devl->list);
}
}
cmd->filter_nodata_only = 0;
/*
* Clear the results of nodata filters that were saved by the
* persistent filter so that the complete set of filters will
* be checked by passes_filter below.
*/
dm_list_iterate_items(devl, &devs)
cmd->filter->wipe(cmd, cmd->filter, devl->dev, NULL);
/*
* Read header from each dev.
* Eliminate non-lvm devs.
* Apply all filters.
*/
log_debug("label_scan_vg_online: read and filter devs");
label_scan_setup_bcache();
dm_list_iterate_items_safe(devl, devl2, &devs) {
struct dev_use *du;
int has_pvid;
if (!label_read_pvid(devl->dev, &has_pvid)) {
log_print_unless_silent("%s cannot read label.", dev_name(devl->dev));
dm_list_del(&devl->list);
dm_list_add(&devs_drop, &devl->list);
continue;
}
if (!has_pvid) {
/* Not an lvm device */
log_print_unless_silent("%s not an lvm device.", dev_name(devl->dev));
dm_list_del(&devl->list);
dm_list_add(&devs_drop, &devl->list);
continue;
}
/*
* filter-deviceid is not being used because of unstable devnames,
* so in place of that check if the pvid is in the devices file.
*/
if (relax_deviceid_filter) {
if (!(du = get_du_for_pvid(cmd, devl->dev->pvid))) {
log_print_unless_silent("%s excluded by devices file (checking PVID).",
dev_name(devl->dev));
dm_list_del(&devl->list);
dm_list_add(&devs_drop, &devl->list);
continue;
} else {
/* Special case matching for devname entries based on pvid. */
log_debug("Match device_id %s %s to %s: matching PVID",
idtype_to_str(du->idtype), du->idname, dev_name(devl->dev));
}
}
/* Applies all filters, including those that need data from dev. */
if (!cmd->filter->passes_filter(cmd, cmd->filter, devl->dev, NULL)) {
log_print_unless_silent("%s excluded: %s.",
dev_name(devl->dev), dev_filtered_reason(devl->dev));
dm_list_del(&devl->list);
dm_list_add(&devs_drop, &devl->list);
}
}
if (relax_deviceid_filter)
cmd->filter_deviceid_skip = 0;
cmd->filter_regex_skip = 0;
free_po_list(&pvs_online);
if (dm_list_empty(&devs)) {
_clear_scan_state(cmd, &devs_drop);
*found_none = 1;
return 1;
}
/*
* Scan devs to populate lvmcache info, which includes the mda info that's
* needed to read vg metadata.
* bcache data from label_read_pvid above is not invalidated so it can
* be reused (more data may need to be read depending on how much of the
* metadata was covered when reading the pvid.)
*/
_scan_list(cmd, NULL, &devs, 0, NULL);
/*
* Check if all PVs from the VG were found after scanning the devs
* produced from the online files. The online files are effectively
* hints that usually work, but are not definitive, so we need to
* be able to fall back to a standard label scan if the online hints
* gave fewer PVs than listed in VG metadata.
*/
if (vgname) {
metadata_pv_count = lvmcache_pvsummary_count(vgname);
if (metadata_pv_count > dm_list_size(&devs)) {
log_debug("Incomplete PV list from online files %d metadata %d.",
dm_list_size(&devs), metadata_pv_count);
_clear_scan_state(cmd, &devs_drop);
_clear_scan_state(cmd, &devs);
*found_incomplete = 1;
return 1;
}
}
*found_all = 1;
return 1;
bad:
_clear_scan_state(cmd, &devs_drop);
_clear_scan_state(cmd, &devs);
free_po_list(&pvs_online);
return 0;
}
/*
* Scan devices on the system to discover which are LVM devices.
* Info about the LVM devices (PVs) is saved in lvmcache in a
* basic/summary form (info/vginfo structs). The vg_read phase
* uses this summary info to know which PVs to look at for
* processing a given VG.
*/
int label_scan(struct cmd_context *cmd)
{
struct dm_list all_devs;
struct dm_list filtered_devs;
struct dm_list scan_devs;
struct dm_list hints_list;
struct dev_iter *iter;
struct device_list *devl, *devl2;
struct device *dev;
uint64_t max_metadata_size_bytes;
int using_hints;
int create_hints = 0; /* NEWHINTS_NONE */
log_debug_devs("Finding devices to scan");
dm_list_init(&all_devs);
dm_list_init(&filtered_devs);
dm_list_init(&scan_devs);
dm_list_init(&hints_list);
if (!label_scan_setup_bcache())
return_0;
/*
* Initialize cache of dm device uuids, which uses a special dm kernel
* feature for efficiently querying many dm devs together. (It's done
* here, before processing the hints file, so that the dm uuid checks
* in hint processing can benefit from the dm uuid cache.)
*/
if (!dm_devs_cache_update())
return_0;
/*
* Creates a list of available devices, does not open or read any,
* and does not filter them. The list of all available devices
* is kept in "dev-cache", and comes from /dev entries or libudev.
* The list of devs found here needs to be filtered to get the
* list of devs we can use. The dev_iter calls using cmd->filter
* are what filters the devs.
*/
if (!setup_devices(cmd)) {
log_error("Failed to set up devices.");
return 0;
}
/*
* If we know that there will be md components with an end
* superblock, then enable the full md filter before label
* scan begins. FIXME: we could skip the full md check on
* devs that are not identified as PVs, but then we'd need
* to do something other than using the standard md filter.
*/
if (cmd->md_component_detection && !cmd->use_full_md_check &&
!strcmp(cmd->md_component_checks, "auto") &&
dev_cache_has_md_with_end_superblock(cmd->dev_types)) {
log_debug("Enable full md component check.");
cmd->use_full_md_check = 1;
}
/*
* Create a list of all devices in dev-cache (all found on the system.)
* Do not apply filters and do not read any (the filter arg is NULL).
* Invalidate bcache data for all devs (there will usually be no bcache
* data to invalidate.)
*/
if (!(iter = dev_iter_create(NULL, 0))) {
log_error("Failed to get device list.");
return 0;
}
while ((dev = dev_iter_get(cmd, iter))) {
if (!(devl = zalloc(sizeof(*devl))))
continue;
devl->dev = dev;
dm_list_add(&all_devs, &devl->list);
/*
* label_scan should not generally be called a second time,
* so this will usually do nothing.
*/
label_scan_invalidate(dev);
}
dev_iter_destroy(iter);
/*
* Exclude devices that fail nodata filters. (Those filters that can be
* checked without reading data from the device.)
*
* The result of checking nodata filters is saved by the "persistent
* filter", and this result needs to be cleared (wiped) so that the
* complete set of filters (including those that require data) can be
* checked in _process_block, where headers have been read.
*
* FIXME: devs that are filtered with data in _process_block
* are not moved to the filtered_devs list like devs filtered
* here without data. Does that have any effect?
*/
log_debug_devs("Filtering devices to scan (nodata)");
cmd->filter_nodata_only = 1;
dm_list_iterate_items_safe(devl, devl2, &all_devs) {
dev = devl->dev;
if (!cmd->filter->passes_filter(cmd, cmd->filter, dev, NULL)) {
dm_list_del(&devl->list);
dm_list_add(&filtered_devs, &devl->list);
if (dev->pvid[0]) {
log_print_unless_silent("Clear pvid and info for filtered dev %s.",
dev_name(dev));
lvmcache_del_dev(dev);
memset(dev->pvid, 0, sizeof(dev->pvid));
}
}
}
log_debug_devs("Filtering devices to scan done (nodata)");
cmd->filter_nodata_only = 0;
dm_list_iterate_items(devl, &all_devs)
cmd->filter->wipe(cmd, cmd->filter, devl->dev, NULL);
dm_list_iterate_items(devl, &filtered_devs)
cmd->filter->wipe(cmd, cmd->filter, devl->dev, NULL);
/*
* In some common cases we can avoid scanning all devices
* by using hints which tell us which devices are PVs, which
* are the only devices we actually need to scan. Without
* hints we need to scan all devs to find which are PVs.
*
* TODO: if the command is using hints and a single vgname
* arg, we can also take the vg lock here, prior to scanning.
* This means we would not need to rescan the PVs in the VG
* in vg_read (skip lvmcache_label_rescan_vg) after the
* vg lock is usually taken. (Some commands are already
* able to avoid rescan in vg_read, but locking early would
* apply to more cases.)
*/
if (!get_hints(cmd, &hints_list, &create_hints, &all_devs, &scan_devs)) {
dm_list_splice(&scan_devs, &all_devs);
dm_list_init(&hints_list);
using_hints = 0;
} else
using_hints = 1;
/*
* If the total number of devices exceeds the soft open file
* limit, then increase the soft limit to the hard/max limit
* in case the number of PVs in scan_devs (it's only the PVs
* which we want to keep open) is higher than the current
* soft limit.
*/
prepare_open_file_limit(cmd, dm_list_size(&scan_devs));
/*
* Do the main scan.
*/
_scan_list(cmd, cmd->filter, &scan_devs, 0, NULL);
/*
* Metadata could be larger than total size of bcache, and bcache
* cannot currently be resized during the command. If this is the
* case (or within reach), warn that io_memory_size needs to be
* set larger.
*
* Even if bcache out of space did not cause a failure during scan, it
* may cause a failure during the next vg_read phase or during vg_write.
*
* If there was an error during scan, we could recreate bcache here
* with a larger size and then restart label_scan. But, this does not
* address the problem of writing new metadata that exceeds the bcache
* size and failing, which would often be hit first, i.e. we'll fail
* to write new metadata exceeding the max size before we have a chance
* to read any metadata with that size, unless we find an existing vg
* that has been previously created with the larger size.
*
* If the largest metadata is within 1MB of the bcache size, then start
* warning.
*/
max_metadata_size_bytes = lvmcache_max_metadata_size();
if (max_metadata_size_bytes + (1024 * 1024) > _current_bcache_size_bytes) {
/* we want bcache to be 1MB larger than the max metadata seen */
uint64_t want_size_kb = (max_metadata_size_bytes / 1024) + 1024;
uint64_t remainder;
if ((remainder = (want_size_kb % 1024)))
want_size_kb = want_size_kb + 1024 - remainder;
log_warn("WARNING: metadata may not be usable with current io_memory_size %d KiB",
io_memory_size());
log_warn("WARNING: increase lvm.conf io_memory_size to at least %llu KiB",
(unsigned long long)want_size_kb);
}
/*
* If we're using hints to limit which devs we scanned, verify
* that those hints were valid, and if not we need to scan the
* rest of the devs.
*/
if (using_hints) {
if (!validate_hints(cmd, &hints_list)) {
log_debug("Will scan %d remaining devices", dm_list_size(&all_devs));
_scan_list(cmd, cmd->filter, &all_devs, 0, NULL);
/* scan_devs are the devs that have been scanned */
dm_list_splice(&scan_devs, &all_devs);
using_hints = 0;
create_hints = 0;
/* invalid hints means a new dev probably appeared and
we should search for any missing pvids again. */
unlink_searched_devnames(cmd);
}
}
free_hints(&hints_list);
/*
* Check if the devices_file content is up to date and
* if not update it.
*/
device_ids_validate(cmd, &scan_devs, using_hints, 0, NULL);
dm_list_iterate_items_safe(devl, devl2, &all_devs) {
dm_list_del(&devl->list);
free(devl);
}
dm_list_iterate_items_safe(devl, devl2, &scan_devs) {
dm_list_del(&devl->list);
free(devl);
}
dm_list_iterate_items_safe(devl, devl2, &filtered_devs) {
dm_list_del(&devl->list);
free(devl);
}
/*
* Look for md components that might have been missed by filter-md
* during the scan. With the label scanning complete we have metadata
* available that can sometimes offer a clue that a dev is actually an
* md component (device name hint, pv size vs dev size). In some of
* those cases we may want to do a full md check on a dev that has been
* scanned. This is done before hints are written so that any devs
* dropped due to being md components will not be included in a new
* hint file.
*/
lvmcache_extra_md_component_checks(cmd);
/*
* If hints were not available/usable, then we scanned all devs,
* and we now know which are PVs. Save this list of PVs we've
* identified as hints for the next command to use.
* (create_hints variable has NEWHINTS_X value which indicates
* the reason for creating the new hints.)
*/
if (create_hints && !cmd->device_ids_invalid)
write_hint_file(cmd, create_hints);
return 1;
}
/*
* Read the header of the disk and if it's a PV
* save the pvid in dev->pvid.
*/
int label_read_pvid(struct device *dev, int *has_pvid)
{
char buf[4096] __attribute__((aligned(8))) = { 0 };
struct label_header *lh;
struct pv_header *pvh;
if (!label_scan_open(dev))
return_0;
/*
* We could do:
* dev_read_bytes(dev, 512, LABEL_SIZE, buf);
* which works, but there's a bcache issue that
* prevents proper invalidation after that.
*/
if (!dev_read_bytes(dev, 0, 4096, buf)) {
label_scan_invalidate(dev);
return_0;
}
if (has_pvid)
*has_pvid = 0;
lh = (struct label_header *)(buf + 512);
if (memcmp(lh->id, LABEL_ID, sizeof(lh->id))) {
/* Not an lvm device */
label_scan_invalidate(dev);
return 1;
}
/*
* wipefs -a just clears the type field, leaving the
* rest of the label_header intact.
*/
if (memcmp(lh->type, LVM2_LABEL, sizeof(lh->type))) {
/* Not an lvm device */
label_scan_invalidate(dev);
return 1;
}
if (has_pvid)
*has_pvid = 1;
pvh = (struct pv_header *)(buf + 512 + 32);
memcpy(dev->pvid, pvh->pv_uuid, ID_LEN);
return 1;
}
/*
* label_scan_devs without invalidating data for the devs first,
* when the caller wants to make use of any bcache data that
* they may have already read.
*/
int label_scan_devs_cached(struct cmd_context *cmd, struct dev_filter *f, struct dm_list *devs)
{
if (!scan_bcache)
return 0;
_scan_list(cmd, f, devs, 0, NULL);
return 1;
}
/*
* Scan and cache lvm data from the listed devices. If a device is already
* scanned and cached, this replaces the previously cached lvm data for the
* device. This is called when vg_read() wants to guarantee that it is using
* the latest data from the devices in the VG (since the scan populated bcache
* without a lock.)
*/
int label_scan_devs(struct cmd_context *cmd, struct dev_filter *f, struct dm_list *devs)
{
struct device_list *devl;
if (!label_scan_setup_bcache())
return_0;
dm_list_iterate_items(devl, devs) {
if (_in_bcache(devl->dev))
_invalidate_di(scan_bcache, devl->dev->bcache_di);
}
_scan_list(cmd, f, devs, 0, NULL);
return 1;
}
int label_scan_devs_rw(struct cmd_context *cmd, struct dev_filter *f, struct dm_list *devs)
{
struct device_list *devl;
if (!label_scan_setup_bcache())
return_0;
dm_list_iterate_items(devl, devs) {
if (_in_bcache(devl->dev))
_invalidate_di(scan_bcache, devl->dev->bcache_di);
devl->dev->flags |= DEV_BCACHE_WRITE;
}
_scan_list(cmd, f, devs, 0, NULL);
return 1;
}
int label_scan_devs_excl(struct cmd_context *cmd, struct dev_filter *f, struct dm_list *devs)
{
struct device_list *devl;
int failed = 0;
dm_list_iterate_items(devl, devs) {
label_scan_invalidate(devl->dev);
/*
* With this flag set, _scan_dev_open() done by
* _scan_list() will do open EXCL
*/
devl->dev->flags |= DEV_BCACHE_EXCL;
devl->dev->flags |= DEV_BCACHE_WRITE;
}
_scan_list(cmd, f, devs, 1, &failed);
if (failed)
return 0;
return 1;
}
void label_scan_invalidate(struct device *dev)
{
if (_in_bcache(dev)) {
_invalidate_di(scan_bcache, dev->bcache_di);
_scan_dev_close(dev);
}
}
/*
* If a PV is stacked on an LV, then the LV is kept open
* in bcache, and needs to be closed so the open fd doesn't
* interfere with processing the LV.
*/
void label_scan_invalidate_lv(struct cmd_context *cmd, struct logical_volume *lv)
{
struct lvinfo lvinfo;
struct device *dev;
dev_t devt;
/* FIXME: use dev_cache_get_existing() with the lv name,
which allow us to skip the getting devno from lv_info. */
if (lv_info(cmd, lv, 0, &lvinfo, 0, 0) && lvinfo.exists) {
/* FIXME: Still unclear what is it supposed to find */
devt = MKDEV(lvinfo.major, lvinfo.minor);
if ((dev = dev_cache_get_by_devt(cmd, devt)))
label_scan_invalidate(dev);
}
}
void label_scan_invalidate_lvs(struct cmd_context *cmd, struct dm_list *lvs)
{
struct lv_list *lvl;
/*
* This is only needed when the command sees PVs stacked on LVs which
* will only happen with scan_lvs=1.
*/
if (!cmd->scan_lvs)
return;
log_debug("Invalidating devs for any PVs on LVs.");
if (dm_devs_cache_use())
dm_devs_cache_label_invalidate(cmd);
else {
dm_list_iterate_items(lvl, lvs)
label_scan_invalidate_lv(cmd, lvl->lv);
}
}
/*
* Empty the bcache of all blocks and close all open fds,
* but keep the bcache set up.
*/
void label_scan_drop(struct cmd_context *cmd)
{
struct dev_iter *iter;
struct device *dev;
if (!(iter = dev_iter_create(NULL, 0)))
return;
while ((dev = dev_iter_get(cmd, iter))) {
cmd->filter->wipe(cmd, cmd->filter, dev, NULL);
if (_in_bcache(dev))
_scan_dev_close(dev);
}
dev_iter_destroy(iter);
}
/*
* Close devices that are open because bcache is holding blocks for them.
* Destroy the bcache.
*/
void label_scan_destroy(struct cmd_context *cmd)
{
if (!scan_bcache)
return;
label_scan_drop(cmd);
bcache_destroy(scan_bcache);
scan_bcache = NULL;
}
/*
* Read (or re-read) and process (or re-process) the data for a device. This
* will reset (clear and repopulate) the bcache and lvmcache info for this
* device. There are only a couple odd places that want to reread a specific
* device, this is not a commonly used function.
*/
int label_scan_dev(struct cmd_context *cmd, struct device *dev)
{
struct dm_list one_dev;
struct device_list *devl;
int failed = 0;
/* scanning is done by list, so make a single item list for this dev */
if (!(devl = zalloc(sizeof(*devl))))
return 0;
devl->dev = dev;
dm_list_init(&one_dev);
dm_list_add(&one_dev, &devl->list);
label_scan_invalidate(dev);
_scan_list(cmd, NULL, &one_dev, 0, &failed);
free(devl);
if (failed)
return 0;
return 1;
}
/*
* This is needed to write to a new non-lvm device.
* Scanning that dev would not keep it open or in
* bcache, but to use bcache_write we need the dev
* to be open so we can use dev->bcache_di to write.
*/
int label_scan_open(struct device *dev)
{
if (!_in_bcache(dev))
return _scan_dev_open(dev);
return 1;
}
int label_scan_open_excl(struct device *dev)
{
if (_in_bcache(dev) && !(dev->flags & DEV_BCACHE_EXCL)) {
log_debug("close and reopen excl %s", dev_name(dev));
_invalidate_di(scan_bcache, dev->bcache_di);
_scan_dev_close(dev);
}
dev->flags |= DEV_BCACHE_EXCL;
dev->flags |= DEV_BCACHE_WRITE;
return label_scan_open(dev);
}
int label_scan_open_rw(struct device *dev)
{
if (_in_bcache(dev) && !(dev->flags & DEV_BCACHE_WRITE)) {
log_debug("close and reopen rw %s", dev_name(dev));
_invalidate_di(scan_bcache, dev->bcache_di);
_scan_dev_close(dev);
}
dev->flags |= DEV_BCACHE_WRITE;
return label_scan_open(dev);
}
int label_scan_reopen_rw(struct device *dev)
{
const char *name;
int flags = 0;
int prev_fd = dev->bcache_fd;
int fd;
if (dm_list_empty(&dev->aliases)) {
log_error("Cannot reopen rw device %u:%u with no valid paths di %d fd %d.",
MAJOR(dev->dev), MINOR(dev->dev), dev->bcache_di, dev->bcache_fd);
return 0;
}
name = dev_name(dev);
if (!name || name[0] != '/') {
log_error("Cannot reopen rw device %u:%u with no valid name di %d fd %d.",
MAJOR(dev->dev), MINOR(dev->dev), dev->bcache_di, dev->bcache_fd);
return 0;
}
if (!(dev->flags & DEV_IN_BCACHE)) {
if ((dev->bcache_fd != -1) || (dev->bcache_di != -1)) {
/* shouldn't happen */
log_debug("Reopen writeable %s uncached fd %d di %d",
dev_name(dev), dev->bcache_fd, dev->bcache_di);
return 0;
}
dev->flags |= DEV_BCACHE_WRITE;
return _scan_dev_open(dev);
}
if ((dev->flags & DEV_BCACHE_WRITE))
return 1;
if (dev->bcache_fd == -1) {
log_error("Failed to open writable %s index %d fd none",
dev_name(dev), dev->bcache_di);
return 0;
}
if (dev->bcache_di == -1) {
log_error("Failed to open writeable %s index none fd %d",
dev_name(dev), dev->bcache_fd);
return 0;
}
flags |= O_DIRECT;
flags |= O_NOATIME;
flags |= O_RDWR;
fd = open(name, flags, 0777);
if (fd < 0) {
log_error("Failed to open rw %s errno %d di %d fd %d.",
dev_name(dev), errno, dev->bcache_di, dev->bcache_fd);
return 0;
}
if (!bcache_change_fd(dev->bcache_di, fd)) {
log_error("Failed to change to rw fd %s di %d fd %d.",
dev_name(dev), dev->bcache_di, fd);
if (close(fd))
log_sys_debug("close", dev_name(dev));
return 0;
}
if (close(dev->bcache_fd))
log_debug("reopen writeable %s close prev errno %d di %d fd %d.",
dev_name(dev), errno, dev->bcache_di, dev->bcache_fd);
dev->flags |= DEV_IN_BCACHE;
dev->flags |= DEV_BCACHE_WRITE;
dev->bcache_fd = fd;
log_debug("reopen writable %s di %d prev %d fd %d",
dev_name(dev), dev->bcache_di, prev_fd, fd);
return 1;
}
bool dev_read_bytes(struct device *dev, uint64_t start, size_t len, void *data)
{
if (!scan_bcache) {
/* Should not happen */
log_error("dev_read bcache not set up %s", dev_name(dev));
return false;
}
if (dev->bcache_di < 0) {
/* This is not often needed. */
if (!label_scan_open(dev)) {
log_error("Error opening device %s for reading at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
return false;
}
}
if (!bcache_read_bytes(scan_bcache, dev->bcache_di, start, len, data)) {
log_error("Error reading device %s at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
label_scan_invalidate(dev);
return false;
}
return true;
}
bool dev_write_bytes(struct device *dev, uint64_t start, size_t len, void *data)
{
if (test_mode())
return true;
if (!scan_bcache) {
/* Should not happen */
log_error("dev_write bcache not set up %s", dev_name(dev));
return false;
}
if (_in_bcache(dev) && !(dev->flags & DEV_BCACHE_WRITE)) {
/* FIXME: avoid tossing out bcache blocks just to replace fd. */
log_debug("close and reopen to write %s", dev_name(dev));
_invalidate_di(scan_bcache, dev->bcache_di);
_scan_dev_close(dev);
dev->flags |= DEV_BCACHE_WRITE;
(void) label_scan_open(dev); /* checked later */
}
if (dev->bcache_di < 0) {
/* This is not often needed. */
dev->flags |= DEV_BCACHE_WRITE;
if (!label_scan_open(dev)) {
log_error("Error opening device %s for writing at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
return false;
}
}
if (!bcache_write_bytes(scan_bcache, dev->bcache_di, start, len, data)) {
log_error("Error writing device %s at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
dev_unset_last_byte(dev);
label_scan_invalidate(dev);
return false;
}
if (!bcache_flush(scan_bcache)) {
log_error("Error writing device %s at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
dev_unset_last_byte(dev);
label_scan_invalidate(dev);
return false;
}
return true;
}
bool dev_invalidate_bytes(struct device *dev, uint64_t start, size_t len)
{
return bcache_invalidate_bytes(scan_bcache, dev->bcache_di, start, len);
}
void dev_invalidate(struct device *dev)
{
bcache_invalidate_di(scan_bcache, dev->bcache_di);
}
bool dev_write_zeros(struct device *dev, uint64_t start, size_t len)
{
return dev_set_bytes(dev, start, len, 0);
}
bool dev_set_bytes(struct device *dev, uint64_t start, size_t len, uint8_t val)
{
bool rv;
if (test_mode())
return true;
if (!scan_bcache) {
log_error("dev_set_bytes bcache not set up %s", dev_name(dev));
return false;
}
if (_in_bcache(dev) && !(dev->flags & DEV_BCACHE_WRITE)) {
log_debug("close and reopen to write %s", dev_name(dev));
_invalidate_di(scan_bcache, dev->bcache_di);
_scan_dev_close(dev);
/* goes to label_scan_open() since bcache_di < 0 */
}
if (dev->bcache_di == -1) {
/* This is not often needed. */
dev->flags |= DEV_BCACHE_WRITE;
if (!label_scan_open(dev)) {
log_error("Error opening device %s for writing at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
return false;
}
}
dev_set_last_byte(dev, start + len);
if (!val)
rv = bcache_zero_bytes(scan_bcache, dev->bcache_di, start, len);
else
rv = bcache_set_bytes(scan_bcache, dev->bcache_di, start, len, val);
if (!rv) {
log_error("Error writing device value %s at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
goto fail;
}
if (!bcache_flush(scan_bcache)) {
log_error("Error writing device %s at %llu length %u.",
dev_name(dev), (unsigned long long)start, (uint32_t)len);
goto fail;
}
dev_unset_last_byte(dev);
return true;
fail:
dev_unset_last_byte(dev);
label_scan_invalidate(dev);
return false;
}
void dev_set_last_byte(struct device *dev, uint64_t offset)
{
unsigned int physical_block_size = 0;
unsigned int logical_block_size = 0;
unsigned int bs;
if (!dev_get_direct_block_sizes(dev, &physical_block_size, &logical_block_size)) {
stack;
return; /* FIXME: error path ? */
}
if ((physical_block_size == 512) && (logical_block_size == 512))
bs = 512;
else if ((physical_block_size == 4096) && (logical_block_size == 4096))
bs = 4096;
else if ((physical_block_size == 512) || (logical_block_size == 512)) {
log_debug("Set last byte mixed block sizes physical %u logical %u using 512",
physical_block_size, logical_block_size);
bs = 512;
} else if ((physical_block_size == 4096) || (logical_block_size == 4096)) {
log_debug("Set last byte mixed block sizes physical %u logical %u using 4096",
physical_block_size, logical_block_size);
bs = 4096;
} else {
log_debug("Set last byte mixed block sizes physical %u logical %u using 512",
physical_block_size, logical_block_size);
bs = 512;
}
bcache_set_last_byte(scan_bcache, dev->bcache_di, offset, bs);
}
void dev_unset_last_byte(struct device *dev)
{
bcache_unset_last_byte(scan_bcache, dev->bcache_di);
}
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