freebsd-skq/sys/boot/zfs/zfs.c
pjd 1b03c5bf41 Finally... Import the latest open-source ZFS version - (SPA) 28.
Few new things available from now on:

- Data deduplication.
- Triple parity RAIDZ (RAIDZ3).
- zfs diff.
- zpool split.
- Snapshot holds.
- zpool import -F. Allows to rewind corrupted pool to earlier
  transaction group.
- Possibility to import pool in read-only mode.

MFC after:	1 month
2011-02-27 19:41:40 +00:00

531 lines
11 KiB
C

/*-
* Copyright (c) 2007 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Stand-alone file reading package.
*/
#include <sys/param.h>
#include <sys/disklabel.h>
#include <sys/time.h>
#include <sys/queue.h>
#include <stddef.h>
#include <stdarg.h>
#include <string.h>
#include <stand.h>
#include <bootstrap.h>
#include "zfsimpl.c"
#define MAXBDDEV 31
static int zfs_open(const char *path, struct open_file *f);
static int zfs_write(struct open_file *f, void *buf, size_t size, size_t *resid);
static int zfs_close(struct open_file *f);
static int zfs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
static off_t zfs_seek(struct open_file *f, off_t offset, int where);
static int zfs_stat(struct open_file *f, struct stat *sb);
static int zfs_readdir(struct open_file *f, struct dirent *d);
struct devsw zfs_dev;
struct fs_ops zfs_fsops = {
"zfs",
zfs_open,
zfs_close,
zfs_read,
zfs_write,
zfs_seek,
zfs_stat,
zfs_readdir
};
/*
* In-core open file.
*/
struct file {
off_t f_seekp; /* seek pointer */
dnode_phys_t f_dnode;
uint64_t f_zap_type; /* zap type for readdir */
uint64_t f_num_leafs; /* number of fzap leaf blocks */
zap_leaf_phys_t *f_zap_leaf; /* zap leaf buffer */
};
/*
* Open a file.
*/
static int
zfs_open(const char *upath, struct open_file *f)
{
spa_t *spa = (spa_t *) f->f_devdata;
struct file *fp;
int rc;
if (f->f_dev != &zfs_dev)
return (EINVAL);
rc = zfs_mount_pool(spa);
if (rc)
return (rc);
/* allocate file system specific data structure */
fp = malloc(sizeof(struct file));
bzero(fp, sizeof(struct file));
f->f_fsdata = (void *)fp;
if (spa->spa_root_objset.os_type != DMU_OST_ZFS) {
printf("Unexpected object set type %llu\n",
spa->spa_root_objset.os_type);
rc = EIO;
goto out;
}
rc = zfs_lookup(spa, upath, &fp->f_dnode);
if (rc)
goto out;
fp->f_seekp = 0;
out:
if (rc) {
f->f_fsdata = NULL;
free(fp);
}
return (rc);
}
static int
zfs_close(struct open_file *f)
{
struct file *fp = (struct file *)f->f_fsdata;
dnode_cache_obj = 0;
f->f_fsdata = (void *)0;
if (fp == (struct file *)0)
return (0);
free(fp);
return (0);
}
/*
* Copy a portion of a file into kernel memory.
* Cross block boundaries when necessary.
*/
static int
zfs_read(struct open_file *f, void *start, size_t size, size_t *resid /* out */)
{
spa_t *spa = (spa_t *) f->f_devdata;
struct file *fp = (struct file *)f->f_fsdata;
struct stat sb;
size_t n;
int rc;
rc = zfs_stat(f, &sb);
if (rc)
return (rc);
n = size;
if (fp->f_seekp + n > sb.st_size)
n = sb.st_size - fp->f_seekp;
rc = dnode_read(spa, &fp->f_dnode, fp->f_seekp, start, n);
if (rc)
return (rc);
if (0) {
int i;
for (i = 0; i < n; i++)
putchar(((char*) start)[i]);
}
fp->f_seekp += n;
if (resid)
*resid = size - n;
return (0);
}
/*
* Don't be silly - the bootstrap has no business writing anything.
*/
static int
zfs_write(struct open_file *f, void *start, size_t size, size_t *resid /* out */)
{
return (EROFS);
}
static off_t
zfs_seek(struct open_file *f, off_t offset, int where)
{
struct file *fp = (struct file *)f->f_fsdata;
switch (where) {
case SEEK_SET:
fp->f_seekp = offset;
break;
case SEEK_CUR:
fp->f_seekp += offset;
break;
case SEEK_END:
{
struct stat sb;
int error;
error = zfs_stat(f, &sb);
if (error != 0) {
errno = error;
return (-1);
}
fp->f_seekp = sb.st_size - offset;
break;
}
default:
errno = EINVAL;
return (-1);
}
return (fp->f_seekp);
}
static int
zfs_stat(struct open_file *f, struct stat *sb)
{
spa_t *spa = (spa_t *) f->f_devdata;
struct file *fp = (struct file *)f->f_fsdata;
return (zfs_dnode_stat(spa, &fp->f_dnode, sb));
}
static int
zfs_readdir(struct open_file *f, struct dirent *d)
{
spa_t *spa = (spa_t *) f->f_devdata;
struct file *fp = (struct file *)f->f_fsdata;
mzap_ent_phys_t mze;
struct stat sb;
size_t bsize = fp->f_dnode.dn_datablkszsec << SPA_MINBLOCKSHIFT;
int rc;
rc = zfs_stat(f, &sb);
if (rc)
return (rc);
if (!S_ISDIR(sb.st_mode))
return (ENOTDIR);
/*
* If this is the first read, get the zap type.
*/
if (fp->f_seekp == 0) {
rc = dnode_read(spa, &fp->f_dnode,
0, &fp->f_zap_type, sizeof(fp->f_zap_type));
if (rc)
return (rc);
if (fp->f_zap_type == ZBT_MICRO) {
fp->f_seekp = offsetof(mzap_phys_t, mz_chunk);
} else {
rc = dnode_read(spa, &fp->f_dnode,
offsetof(zap_phys_t, zap_num_leafs),
&fp->f_num_leafs,
sizeof(fp->f_num_leafs));
if (rc)
return (rc);
fp->f_seekp = bsize;
fp->f_zap_leaf = (zap_leaf_phys_t *)malloc(bsize);
rc = dnode_read(spa, &fp->f_dnode,
fp->f_seekp,
fp->f_zap_leaf,
bsize);
if (rc)
return (rc);
}
}
if (fp->f_zap_type == ZBT_MICRO) {
mzap_next:
if (fp->f_seekp >= bsize)
return (ENOENT);
rc = dnode_read(spa, &fp->f_dnode,
fp->f_seekp, &mze, sizeof(mze));
if (rc)
return (rc);
fp->f_seekp += sizeof(mze);
if (!mze.mze_name[0])
goto mzap_next;
d->d_fileno = ZFS_DIRENT_OBJ(mze.mze_value);
d->d_type = ZFS_DIRENT_TYPE(mze.mze_value);
strcpy(d->d_name, mze.mze_name);
d->d_namlen = strlen(d->d_name);
return (0);
} else {
zap_leaf_t zl;
zap_leaf_chunk_t *zc, *nc;
int chunk;
size_t namelen;
char *p;
uint64_t value;
/*
* Initialise this so we can use the ZAP size
* calculating macros.
*/
zl.l_bs = ilog2(bsize);
zl.l_phys = fp->f_zap_leaf;
/*
* Figure out which chunk we are currently looking at
* and consider seeking to the next leaf. We use the
* low bits of f_seekp as a simple chunk index.
*/
fzap_next:
chunk = fp->f_seekp & (bsize - 1);
if (chunk == ZAP_LEAF_NUMCHUNKS(&zl)) {
fp->f_seekp = (fp->f_seekp & ~(bsize - 1)) + bsize;
chunk = 0;
/*
* Check for EOF and read the new leaf.
*/
if (fp->f_seekp >= bsize * fp->f_num_leafs)
return (ENOENT);
rc = dnode_read(spa, &fp->f_dnode,
fp->f_seekp,
fp->f_zap_leaf,
bsize);
if (rc)
return (rc);
}
zc = &ZAP_LEAF_CHUNK(&zl, chunk);
fp->f_seekp++;
if (zc->l_entry.le_type != ZAP_CHUNK_ENTRY)
goto fzap_next;
namelen = zc->l_entry.le_name_length;
if (namelen > sizeof(d->d_name))
namelen = sizeof(d->d_name);
/*
* Paste the name back together.
*/
nc = &ZAP_LEAF_CHUNK(&zl, zc->l_entry.le_name_chunk);
p = d->d_name;
while (namelen > 0) {
int len;
len = namelen;
if (len > ZAP_LEAF_ARRAY_BYTES)
len = ZAP_LEAF_ARRAY_BYTES;
memcpy(p, nc->l_array.la_array, len);
p += len;
namelen -= len;
nc = &ZAP_LEAF_CHUNK(&zl, nc->l_array.la_next);
}
d->d_name[sizeof(d->d_name) - 1] = 0;
/*
* Assume the first eight bytes of the value are
* a uint64_t.
*/
value = fzap_leaf_value(&zl, zc);
d->d_fileno = ZFS_DIRENT_OBJ(value);
d->d_type = ZFS_DIRENT_TYPE(value);
d->d_namlen = strlen(d->d_name);
return (0);
}
}
static int
vdev_read(vdev_t *vdev, void *priv, off_t offset, void *buf, size_t size)
{
int fd;
fd = (uintptr_t) priv;
lseek(fd, offset, SEEK_SET);
if (read(fd, buf, size) == size) {
return 0;
} else {
return (EIO);
}
}
/*
* Convert a pool guid to a 'unit number' suitable for use with zfs_dev_open.
*/
int
zfs_guid_to_unit(uint64_t guid)
{
spa_t *spa;
int unit;
unit = 0;
STAILQ_FOREACH(spa, &zfs_pools, spa_link) {
if (spa->spa_guid == guid)
return unit;
unit++;
}
return (-1);
}
static int
zfs_dev_init(void)
{
char devname[512];
int unit, slice;
int fd;
/*
* Open all the disks we can find and see if we can reconstruct
* ZFS pools from them. Bogusly assumes that the disks are named
* diskN, diskNpM or diskNsM.
*/
zfs_init();
for (unit = 0; unit < MAXBDDEV; unit++) {
sprintf(devname, "disk%d:", unit);
fd = open(devname, O_RDONLY);
if (fd == -1)
continue;
/*
* If we find a vdev, the zfs code will eat the fd, otherwise
* we close it.
*/
if (vdev_probe(vdev_read, (void*) (uintptr_t) fd, 0))
close(fd);
for (slice = 1; slice <= 128; slice++) {
sprintf(devname, "disk%dp%d:", unit, slice);
fd = open(devname, O_RDONLY);
if (fd == -1) {
sprintf(devname, "disk%ds%d:", unit, slice);
fd = open(devname, O_RDONLY);
if (fd == -1)
continue;
}
if (vdev_probe(vdev_read, (void*) (uintptr_t) fd, 0))
close(fd);
}
}
return (0);
}
/*
* Print information about ZFS pools
*/
static void
zfs_dev_print(int verbose)
{
spa_t *spa;
char line[80];
int unit;
if (verbose) {
spa_all_status();
return;
}
unit = 0;
STAILQ_FOREACH(spa, &zfs_pools, spa_link) {
sprintf(line, " zfs%d: %s\n", unit, spa->spa_name);
pager_output(line);
unit++;
}
}
/*
* Attempt to open the pool described by (dev) for use by (f).
*/
static int
zfs_dev_open(struct open_file *f, ...)
{
va_list args;
struct devdesc *dev;
int unit, i;
spa_t *spa;
va_start(args, f);
dev = va_arg(args, struct devdesc*);
va_end(args);
/*
* We mostly ignore the stuff that devopen sends us. For now,
* use the unit to find a pool - later we will override the
* devname parsing so that we can name a pool and a fs within
* the pool.
*/
unit = dev->d_unit;
i = 0;
STAILQ_FOREACH(spa, &zfs_pools, spa_link) {
if (i == unit)
break;
i++;
}
if (!spa) {
return (ENXIO);
}
f->f_devdata = spa;
free(dev);
return (0);
}
static int
zfs_dev_close(struct open_file *f)
{
f->f_devdata = NULL;
return (0);
}
static int
zfs_dev_strategy(void *devdata, int rw, daddr_t dblk, size_t size, char *buf, size_t *rsize)
{
return (ENOSYS);
}
struct devsw zfs_dev = {
.dv_name = "zfs",
.dv_type = DEVT_ZFS,
.dv_init = zfs_dev_init,
.dv_strategy = zfs_dev_strategy,
.dv_open = zfs_dev_open,
.dv_close = zfs_dev_close,
.dv_ioctl = noioctl,
.dv_print = zfs_dev_print,
.dv_cleanup = NULL
};