zfs/lib/libzpool/kernel.c

1406 lines
27 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2018 by Delphix. All rights reserved.
* Copyright (c) 2016 Actifio, Inc. All rights reserved.
*/
#include <assert.h>
#include <fcntl.h>
#include <libgen.h>
#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/crypto/icp.h>
#include <sys/processor.h>
#include <sys/rrwlock.h>
#include <sys/spa.h>
#include <sys/stat.h>
#include <sys/systeminfo.h>
#include <sys/time.h>
#include <sys/utsname.h>
#include <sys/zfs_context.h>
#include <sys/zfs_onexit.h>
#include <sys/zvol.h>
#include <zfs_fletcher.h>
#include <zlib.h>
/*
* Emulation of kernel services in userland.
*/
uint64_t physmem;
char hw_serial[HW_HOSTID_LEN];
struct utsname hw_utsname;
/* If set, all blocks read will be copied to the specified directory. */
char *vn_dumpdir = NULL;
/* this only exists to have its address taken */
struct proc p0;
/*
* =========================================================================
* threads
* =========================================================================
*
* TS_STACK_MIN is dictated by the minimum allowed pthread stack size. While
* TS_STACK_MAX is somewhat arbitrary, it was selected to be large enough for
* the expected stack depth while small enough to avoid exhausting address
* space with high thread counts.
*/
#define TS_STACK_MIN MAX(PTHREAD_STACK_MIN, 32768)
#define TS_STACK_MAX (256 * 1024)
/*ARGSUSED*/
kthread_t *
zk_thread_create(void (*func)(void *), void *arg, size_t stksize, int state)
{
pthread_attr_t attr;
pthread_t tid;
char *stkstr;
int detachstate = PTHREAD_CREATE_DETACHED;
VERIFY0(pthread_attr_init(&attr));
if (state & TS_JOINABLE)
detachstate = PTHREAD_CREATE_JOINABLE;
VERIFY0(pthread_attr_setdetachstate(&attr, detachstate));
/*
* We allow the default stack size in user space to be specified by
* setting the ZFS_STACK_SIZE environment variable. This allows us
* the convenience of observing and debugging stack overruns in
* user space. Explicitly specified stack sizes will be honored.
* The usage of ZFS_STACK_SIZE is discussed further in the
* ENVIRONMENT VARIABLES sections of the ztest(1) man page.
*/
if (stksize == 0) {
stkstr = getenv("ZFS_STACK_SIZE");
if (stkstr == NULL)
stksize = TS_STACK_MAX;
else
stksize = MAX(atoi(stkstr), TS_STACK_MIN);
}
VERIFY3S(stksize, >, 0);
stksize = P2ROUNDUP(MAX(stksize, TS_STACK_MIN), PAGESIZE);
/*
* If this ever fails, it may be because the stack size is not a
* multiple of system page size.
*/
VERIFY0(pthread_attr_setstacksize(&attr, stksize));
VERIFY0(pthread_attr_setguardsize(&attr, PAGESIZE));
VERIFY0(pthread_create(&tid, &attr, (void *(*)(void *))func, arg));
VERIFY0(pthread_attr_destroy(&attr));
return ((void *)(uintptr_t)tid);
}
/*
* =========================================================================
* kstats
* =========================================================================
*/
/*ARGSUSED*/
kstat_t *
kstat_create(const char *module, int instance, const char *name,
const char *class, uchar_t type, ulong_t ndata, uchar_t ks_flag)
{
return (NULL);
}
/*ARGSUSED*/
void
kstat_install(kstat_t *ksp)
{}
/*ARGSUSED*/
void
kstat_delete(kstat_t *ksp)
{}
/*ARGSUSED*/
void
kstat_waitq_enter(kstat_io_t *kiop)
{}
/*ARGSUSED*/
void
kstat_waitq_exit(kstat_io_t *kiop)
{}
/*ARGSUSED*/
void
kstat_runq_enter(kstat_io_t *kiop)
{}
/*ARGSUSED*/
void
kstat_runq_exit(kstat_io_t *kiop)
{}
/*ARGSUSED*/
void
kstat_waitq_to_runq(kstat_io_t *kiop)
{}
/*ARGSUSED*/
void
kstat_runq_back_to_waitq(kstat_io_t *kiop)
{}
void
kstat_set_raw_ops(kstat_t *ksp,
int (*headers)(char *buf, size_t size),
int (*data)(char *buf, size_t size, void *data),
void *(*addr)(kstat_t *ksp, loff_t index))
{}
/*
* =========================================================================
* mutexes
* =========================================================================
*/
void
mutex_init(kmutex_t *mp, char *name, int type, void *cookie)
{
VERIFY0(pthread_mutex_init(&mp->m_lock, NULL));
memset(&mp->m_owner, 0, sizeof (pthread_t));
}
void
mutex_destroy(kmutex_t *mp)
{
VERIFY0(pthread_mutex_destroy(&mp->m_lock));
}
void
mutex_enter(kmutex_t *mp)
{
VERIFY0(pthread_mutex_lock(&mp->m_lock));
mp->m_owner = pthread_self();
}
int
mutex_tryenter(kmutex_t *mp)
{
int error;
error = pthread_mutex_trylock(&mp->m_lock);
if (error == 0) {
mp->m_owner = pthread_self();
return (1);
} else {
VERIFY3S(error, ==, EBUSY);
return (0);
}
}
void
mutex_exit(kmutex_t *mp)
{
memset(&mp->m_owner, 0, sizeof (pthread_t));
VERIFY0(pthread_mutex_unlock(&mp->m_lock));
}
/*
* =========================================================================
* rwlocks
* =========================================================================
*/
void
rw_init(krwlock_t *rwlp, char *name, int type, void *arg)
{
VERIFY0(pthread_rwlock_init(&rwlp->rw_lock, NULL));
rwlp->rw_readers = 0;
rwlp->rw_owner = 0;
}
void
rw_destroy(krwlock_t *rwlp)
{
VERIFY0(pthread_rwlock_destroy(&rwlp->rw_lock));
}
void
rw_enter(krwlock_t *rwlp, krw_t rw)
{
if (rw == RW_READER) {
VERIFY0(pthread_rwlock_rdlock(&rwlp->rw_lock));
atomic_inc_uint(&rwlp->rw_readers);
} else {
VERIFY0(pthread_rwlock_wrlock(&rwlp->rw_lock));
rwlp->rw_owner = pthread_self();
}
}
void
rw_exit(krwlock_t *rwlp)
{
if (RW_READ_HELD(rwlp))
atomic_dec_uint(&rwlp->rw_readers);
else
rwlp->rw_owner = 0;
VERIFY0(pthread_rwlock_unlock(&rwlp->rw_lock));
}
int
rw_tryenter(krwlock_t *rwlp, krw_t rw)
{
int error;
if (rw == RW_READER)
error = pthread_rwlock_tryrdlock(&rwlp->rw_lock);
else
error = pthread_rwlock_trywrlock(&rwlp->rw_lock);
if (error == 0) {
if (rw == RW_READER)
atomic_inc_uint(&rwlp->rw_readers);
else
rwlp->rw_owner = pthread_self();
return (1);
}
VERIFY3S(error, ==, EBUSY);
return (0);
}
/* ARGSUSED */
uint32_t
zone_get_hostid(void *zonep)
{
/*
* We're emulating the system's hostid in userland.
*/
return (strtoul(hw_serial, NULL, 10));
}
int
rw_tryupgrade(krwlock_t *rwlp)
{
return (0);
}
/*
* =========================================================================
* condition variables
* =========================================================================
*/
void
cv_init(kcondvar_t *cv, char *name, int type, void *arg)
{
VERIFY0(pthread_cond_init(cv, NULL));
}
void
cv_destroy(kcondvar_t *cv)
{
VERIFY0(pthread_cond_destroy(cv));
}
void
cv_wait(kcondvar_t *cv, kmutex_t *mp)
{
memset(&mp->m_owner, 0, sizeof (pthread_t));
VERIFY0(pthread_cond_wait(cv, &mp->m_lock));
mp->m_owner = pthread_self();
}
int
cv_wait_sig(kcondvar_t *cv, kmutex_t *mp)
{
cv_wait(cv, mp);
return (1);
}
int
cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime)
{
int error;
struct timeval tv;
struct timespec ts;
clock_t delta;
delta = abstime - ddi_get_lbolt();
if (delta <= 0)
return (-1);
VERIFY(gettimeofday(&tv, NULL) == 0);
ts.tv_sec = tv.tv_sec + delta / hz;
ts.tv_nsec = tv.tv_usec * NSEC_PER_USEC + (delta % hz) * (NANOSEC / hz);
if (ts.tv_nsec >= NANOSEC) {
ts.tv_sec++;
ts.tv_nsec -= NANOSEC;
}
memset(&mp->m_owner, 0, sizeof (pthread_t));
error = pthread_cond_timedwait(cv, &mp->m_lock, &ts);
mp->m_owner = pthread_self();
if (error == ETIMEDOUT)
return (-1);
VERIFY0(error);
return (1);
}
/*ARGSUSED*/
int
cv_timedwait_hires(kcondvar_t *cv, kmutex_t *mp, hrtime_t tim, hrtime_t res,
int flag)
{
int error;
struct timeval tv;
struct timespec ts;
hrtime_t delta;
ASSERT(flag == 0 || flag == CALLOUT_FLAG_ABSOLUTE);
delta = tim;
if (flag & CALLOUT_FLAG_ABSOLUTE)
delta -= gethrtime();
if (delta <= 0)
return (-1);
VERIFY0(gettimeofday(&tv, NULL));
ts.tv_sec = tv.tv_sec + delta / NANOSEC;
ts.tv_nsec = tv.tv_usec * NSEC_PER_USEC + (delta % NANOSEC);
if (ts.tv_nsec >= NANOSEC) {
ts.tv_sec++;
ts.tv_nsec -= NANOSEC;
}
memset(&mp->m_owner, 0, sizeof (pthread_t));
error = pthread_cond_timedwait(cv, &mp->m_lock, &ts);
mp->m_owner = pthread_self();
if (error == ETIMEDOUT)
return (-1);
VERIFY0(error);
return (1);
}
void
cv_signal(kcondvar_t *cv)
{
VERIFY0(pthread_cond_signal(cv));
}
void
cv_broadcast(kcondvar_t *cv)
{
VERIFY0(pthread_cond_broadcast(cv));
}
/*
* =========================================================================
* procfs list
* =========================================================================
*/
void
seq_printf(struct seq_file *m, const char *fmt, ...)
{}
void
procfs_list_install(const char *module,
const char *name,
mode_t mode,
procfs_list_t *procfs_list,
int (*show)(struct seq_file *f, void *p),
int (*show_header)(struct seq_file *f),
int (*clear)(procfs_list_t *procfs_list),
size_t procfs_list_node_off)
{
mutex_init(&procfs_list->pl_lock, NULL, MUTEX_DEFAULT, NULL);
list_create(&procfs_list->pl_list,
procfs_list_node_off + sizeof (procfs_list_node_t),
procfs_list_node_off + offsetof(procfs_list_node_t, pln_link));
procfs_list->pl_next_id = 1;
procfs_list->pl_node_offset = procfs_list_node_off;
}
void
procfs_list_uninstall(procfs_list_t *procfs_list)
{}
void
procfs_list_destroy(procfs_list_t *procfs_list)
{
ASSERT(list_is_empty(&procfs_list->pl_list));
list_destroy(&procfs_list->pl_list);
mutex_destroy(&procfs_list->pl_lock);
}
#define NODE_ID(procfs_list, obj) \
(((procfs_list_node_t *)(((char *)obj) + \
(procfs_list)->pl_node_offset))->pln_id)
void
procfs_list_add(procfs_list_t *procfs_list, void *p)
{
ASSERT(MUTEX_HELD(&procfs_list->pl_lock));
NODE_ID(procfs_list, p) = procfs_list->pl_next_id++;
list_insert_tail(&procfs_list->pl_list, p);
}
/*
* =========================================================================
* vnode operations
* =========================================================================
*/
/*
* =========================================================================
* Figure out which debugging statements to print
* =========================================================================
*/
static char *dprintf_string;
static int dprintf_print_all;
int
dprintf_find_string(const char *string)
{
char *tmp_str = dprintf_string;
int len = strlen(string);
/*
* Find out if this is a string we want to print.
* String format: file1.c,function_name1,file2.c,file3.c
*/
while (tmp_str != NULL) {
if (strncmp(tmp_str, string, len) == 0 &&
(tmp_str[len] == ',' || tmp_str[len] == '\0'))
return (1);
tmp_str = strchr(tmp_str, ',');
if (tmp_str != NULL)
tmp_str++; /* Get rid of , */
}
return (0);
}
void
dprintf_setup(int *argc, char **argv)
{
int i, j;
/*
* Debugging can be specified two ways: by setting the
* environment variable ZFS_DEBUG, or by including a
* "debug=..." argument on the command line. The command
* line setting overrides the environment variable.
*/
for (i = 1; i < *argc; i++) {
int len = strlen("debug=");
/* First look for a command line argument */
if (strncmp("debug=", argv[i], len) == 0) {
dprintf_string = argv[i] + len;
/* Remove from args */
for (j = i; j < *argc; j++)
argv[j] = argv[j+1];
argv[j] = NULL;
(*argc)--;
}
}
if (dprintf_string == NULL) {
/* Look for ZFS_DEBUG environment variable */
dprintf_string = getenv("ZFS_DEBUG");
}
/*
* Are we just turning on all debugging?
*/
if (dprintf_find_string("on"))
dprintf_print_all = 1;
if (dprintf_string != NULL)
zfs_flags |= ZFS_DEBUG_DPRINTF;
}
/*
* =========================================================================
* debug printfs
* =========================================================================
*/
void
__dprintf(boolean_t dprint, const char *file, const char *func,
int line, const char *fmt, ...)
{
const char *newfile;
va_list adx;
/*
* Get rid of annoying "../common/" prefix to filename.
*/
newfile = strrchr(file, '/');
if (newfile != NULL) {
newfile = newfile + 1; /* Get rid of leading / */
} else {
newfile = file;
}
if (dprint) {
/* dprintf messages are printed immediately */
if (!dprintf_print_all &&
!dprintf_find_string(newfile) &&
!dprintf_find_string(func))
return;
/* Print out just the function name if requested */
flockfile(stdout);
if (dprintf_find_string("pid"))
(void) printf("%d ", getpid());
if (dprintf_find_string("tid"))
(void) printf("%ju ",
(uintmax_t)(uintptr_t)pthread_self());
if (dprintf_find_string("cpu"))
(void) printf("%u ", getcpuid());
if (dprintf_find_string("time"))
(void) printf("%llu ", gethrtime());
if (dprintf_find_string("long"))
(void) printf("%s, line %d: ", newfile, line);
(void) printf("dprintf: %s: ", func);
va_start(adx, fmt);
(void) vprintf(fmt, adx);
va_end(adx);
funlockfile(stdout);
} else {
/* zfs_dbgmsg is logged for dumping later */
size_t size;
char *buf;
int i;
size = 1024;
buf = umem_alloc(size, UMEM_NOFAIL);
i = snprintf(buf, size, "%s:%d:%s(): ", newfile, line, func);
if (i < size) {
va_start(adx, fmt);
(void) vsnprintf(buf + i, size - i, fmt, adx);
va_end(adx);
}
__zfs_dbgmsg(buf);
umem_free(buf, size);
}
}
/*
* =========================================================================
* cmn_err() and panic()
* =========================================================================
*/
static char ce_prefix[CE_IGNORE][10] = { "", "NOTICE: ", "WARNING: ", "" };
static char ce_suffix[CE_IGNORE][2] = { "", "\n", "\n", "" };
void
vpanic(const char *fmt, va_list adx)
{
(void) fprintf(stderr, "error: ");
(void) vfprintf(stderr, fmt, adx);
(void) fprintf(stderr, "\n");
abort(); /* think of it as a "user-level crash dump" */
}
void
panic(const char *fmt, ...)
{
va_list adx;
va_start(adx, fmt);
vpanic(fmt, adx);
va_end(adx);
}
void
vcmn_err(int ce, const char *fmt, va_list adx)
{
if (ce == CE_PANIC)
vpanic(fmt, adx);
if (ce != CE_NOTE) { /* suppress noise in userland stress testing */
(void) fprintf(stderr, "%s", ce_prefix[ce]);
(void) vfprintf(stderr, fmt, adx);
(void) fprintf(stderr, "%s", ce_suffix[ce]);
}
}
/*PRINTFLIKE2*/
void
cmn_err(int ce, const char *fmt, ...)
{
va_list adx;
va_start(adx, fmt);
vcmn_err(ce, fmt, adx);
va_end(adx);
}
/*
* =========================================================================
* misc routines
* =========================================================================
*/
void
delay(clock_t ticks)
{
(void) poll(0, 0, ticks * (1000 / hz));
}
/*
* Find highest one bit set.
* Returns bit number + 1 of highest bit that is set, otherwise returns 0.
* The __builtin_clzll() function is supported by both GCC and Clang.
*/
int
highbit64(uint64_t i)
{
if (i == 0)
return (0);
return (NBBY * sizeof (uint64_t) - __builtin_clzll(i));
}
/*
* Find lowest one bit set.
* Returns bit number + 1 of lowest bit that is set, otherwise returns 0.
* The __builtin_ffsll() function is supported by both GCC and Clang.
*/
int
lowbit64(uint64_t i)
{
if (i == 0)
return (0);
return (__builtin_ffsll(i));
}
char *random_path = "/dev/random";
char *urandom_path = "/dev/urandom";
static int random_fd = -1, urandom_fd = -1;
void
random_init(void)
{
VERIFY((random_fd = open(random_path, O_RDONLY)) != -1);
VERIFY((urandom_fd = open(urandom_path, O_RDONLY)) != -1);
}
void
random_fini(void)
{
close(random_fd);
close(urandom_fd);
random_fd = -1;
urandom_fd = -1;
}
static int
random_get_bytes_common(uint8_t *ptr, size_t len, int fd)
{
size_t resid = len;
ssize_t bytes;
ASSERT(fd != -1);
while (resid != 0) {
bytes = read(fd, ptr, resid);
ASSERT3S(bytes, >=, 0);
ptr += bytes;
resid -= bytes;
}
return (0);
}
int
random_get_bytes(uint8_t *ptr, size_t len)
{
return (random_get_bytes_common(ptr, len, random_fd));
}
int
random_get_pseudo_bytes(uint8_t *ptr, size_t len)
{
return (random_get_bytes_common(ptr, len, urandom_fd));
}
int
ddi_strtoul(const char *hw_serial, char **nptr, int base, unsigned long *result)
{
char *end;
*result = strtoul(hw_serial, &end, base);
if (*result == 0)
return (errno);
return (0);
}
int
ddi_strtoull(const char *str, char **nptr, int base, u_longlong_t *result)
{
char *end;
*result = strtoull(str, &end, base);
if (*result == 0)
return (errno);
return (0);
}
utsname_t *
utsname(void)
{
return (&hw_utsname);
}
/*
* =========================================================================
* kernel emulation setup & teardown
* =========================================================================
*/
static int
umem_out_of_memory(void)
{
char errmsg[] = "out of memory -- generating core dump\n";
(void) fprintf(stderr, "%s", errmsg);
abort();
return (0);
}
void
kernel_init(int mode)
{
extern uint_t rrw_tsd_key;
umem_nofail_callback(umem_out_of_memory);
physmem = sysconf(_SC_PHYS_PAGES);
dprintf("physmem = %llu pages (%.2f GB)\n", physmem,
(double)physmem * sysconf(_SC_PAGE_SIZE) / (1ULL << 30));
(void) snprintf(hw_serial, sizeof (hw_serial), "%ld",
(mode & SPA_MODE_WRITE) ? get_system_hostid() : 0);
random_init();
VERIFY0(uname(&hw_utsname));
system_taskq_init();
icp_init();
spa_init((spa_mode_t)mode);
fletcher_4_init();
tsd_create(&rrw_tsd_key, rrw_tsd_destroy);
}
void
kernel_fini(void)
{
fletcher_4_fini();
spa_fini();
icp_fini();
system_taskq_fini();
random_fini();
}
uid_t
crgetuid(cred_t *cr)
{
return (0);
}
uid_t
crgetruid(cred_t *cr)
{
return (0);
}
gid_t
crgetgid(cred_t *cr)
{
return (0);
}
int
crgetngroups(cred_t *cr)
{
return (0);
}
gid_t *
crgetgroups(cred_t *cr)
{
return (NULL);
}
int
zfs_secpolicy_snapshot_perms(const char *name, cred_t *cr)
{
return (0);
}
int
zfs_secpolicy_rename_perms(const char *from, const char *to, cred_t *cr)
{
return (0);
}
int
zfs_secpolicy_destroy_perms(const char *name, cred_t *cr)
{
return (0);
}
int
secpolicy_zfs(const cred_t *cr)
{
return (0);
}
int
secpolicy_zfs_proc(const cred_t *cr, proc_t *proc)
{
return (0);
}
ksiddomain_t *
ksid_lookupdomain(const char *dom)
{
ksiddomain_t *kd;
kd = umem_zalloc(sizeof (ksiddomain_t), UMEM_NOFAIL);
kd->kd_name = spa_strdup(dom);
return (kd);
}
void
ksiddomain_rele(ksiddomain_t *ksid)
{
spa_strfree(ksid->kd_name);
umem_free(ksid, sizeof (ksiddomain_t));
}
char *
kmem_vasprintf(const char *fmt, va_list adx)
{
char *buf = NULL;
va_list adx_copy;
va_copy(adx_copy, adx);
VERIFY(vasprintf(&buf, fmt, adx_copy) != -1);
va_end(adx_copy);
return (buf);
}
char *
kmem_asprintf(const char *fmt, ...)
{
char *buf = NULL;
va_list adx;
va_start(adx, fmt);
VERIFY(vasprintf(&buf, fmt, adx) != -1);
va_end(adx);
return (buf);
}
/* ARGSUSED */
int
zfs_onexit_fd_hold(int fd, minor_t *minorp)
{
*minorp = 0;
return (0);
}
/* ARGSUSED */
void
zfs_onexit_fd_rele(int fd)
{
}
/* ARGSUSED */
int
zfs_onexit_add_cb(minor_t minor, void (*func)(void *), void *data,
uint64_t *action_handle)
{
return (0);
}
fstrans_cookie_t
spl_fstrans_mark(void)
{
return ((fstrans_cookie_t)0);
}
void
spl_fstrans_unmark(fstrans_cookie_t cookie)
{
}
int
__spl_pf_fstrans_check(void)
{
return (0);
}
int
kmem_cache_reap_active(void)
{
return (0);
}
void *zvol_tag = "zvol_tag";
void
zvol_create_minor(const char *name)
{
}
void
zvol_create_minors_recursive(const char *name)
{
}
void
zvol_remove_minors(spa_t *spa, const char *name, boolean_t async)
{
}
void
zvol_rename_minors(spa_t *spa, const char *oldname, const char *newname,
boolean_t async)
{
}
/*
* Open file
*
* path - fully qualified path to file
* flags - file attributes O_READ / O_WRITE / O_EXCL
* fpp - pointer to return file pointer
*
* Returns 0 on success underlying error on failure.
*/
int
zfs_file_open(const char *path, int flags, int mode, zfs_file_t **fpp)
{
int fd = -1;
int dump_fd = -1;
int err;
int old_umask = 0;
zfs_file_t *fp;
struct stat64 st;
if (!(flags & O_CREAT) && stat64(path, &st) == -1)
return (errno);
if (!(flags & O_CREAT) && S_ISBLK(st.st_mode))
flags |= O_DIRECT;
if (flags & O_CREAT)
old_umask = umask(0);
fd = open64(path, flags, mode);
if (fd == -1)
return (errno);
if (flags & O_CREAT)
(void) umask(old_umask);
if (vn_dumpdir != NULL) {
char *dumppath = umem_zalloc(MAXPATHLEN, UMEM_NOFAIL);
char *inpath = basename((char *)(uintptr_t)path);
(void) snprintf(dumppath, MAXPATHLEN,
"%s/%s", vn_dumpdir, inpath);
dump_fd = open64(dumppath, O_CREAT | O_WRONLY, 0666);
umem_free(dumppath, MAXPATHLEN);
if (dump_fd == -1) {
err = errno;
close(fd);
return (err);
}
} else {
dump_fd = -1;
}
(void) fcntl(fd, F_SETFD, FD_CLOEXEC);
fp = umem_zalloc(sizeof (zfs_file_t), UMEM_NOFAIL);
fp->f_fd = fd;
fp->f_dump_fd = dump_fd;
*fpp = fp;
return (0);
}
void
zfs_file_close(zfs_file_t *fp)
{
close(fp->f_fd);
if (fp->f_dump_fd != -1)
close(fp->f_dump_fd);
umem_free(fp, sizeof (zfs_file_t));
}
/*
* Stateful write - use os internal file pointer to determine where to
* write and update on successful completion.
*
* fp - pointer to file (pipe, socket, etc) to write to
* buf - buffer to write
* count - # of bytes to write
* resid - pointer to count of unwritten bytes (if short write)
*
* Returns 0 on success errno on failure.
*/
int
zfs_file_write(zfs_file_t *fp, const void *buf, size_t count, ssize_t *resid)
{
ssize_t rc;
rc = write(fp->f_fd, buf, count);
if (rc < 0)
return (errno);
if (resid) {
*resid = count - rc;
} else if (rc != count) {
return (EIO);
}
return (0);
}
/*
* Stateless write - os internal file pointer is not updated.
*
* fp - pointer to file (pipe, socket, etc) to write to
* buf - buffer to write
* count - # of bytes to write
* off - file offset to write to (only valid for seekable types)
* resid - pointer to count of unwritten bytes
*
* Returns 0 on success errno on failure.
*/
int
zfs_file_pwrite(zfs_file_t *fp, const void *buf,
size_t count, loff_t pos, ssize_t *resid)
{
ssize_t rc, split, done;
int sectors;
/*
* To simulate partial disk writes, we split writes into two
* system calls so that the process can be killed in between.
* This is used by ztest to simulate realistic failure modes.
*/
sectors = count >> SPA_MINBLOCKSHIFT;
split = (sectors > 0 ? rand() % sectors : 0) << SPA_MINBLOCKSHIFT;
rc = pwrite64(fp->f_fd, buf, split, pos);
if (rc != -1) {
done = rc;
rc = pwrite64(fp->f_fd, (char *)buf + split,
count - split, pos + split);
}
#ifdef __linux__
if (rc == -1 && errno == EINVAL) {
/*
* Under Linux, this most likely means an alignment issue
* (memory or disk) due to O_DIRECT, so we abort() in order
* to catch the offender.
*/
abort();
}
#endif
if (rc < 0)
return (errno);
done += rc;
if (resid) {
*resid = count - done;
} else if (done != count) {
return (EIO);
}
return (0);
}
/*
* Stateful read - use os internal file pointer to determine where to
* read and update on successful completion.
*
* fp - pointer to file (pipe, socket, etc) to read from
* buf - buffer to write
* count - # of bytes to read
* resid - pointer to count of unread bytes (if short read)
*
* Returns 0 on success errno on failure.
*/
int
zfs_file_read(zfs_file_t *fp, void *buf, size_t count, ssize_t *resid)
{
int rc;
rc = read(fp->f_fd, buf, count);
if (rc < 0)
return (errno);
if (resid) {
*resid = count - rc;
} else if (rc != count) {
return (EIO);
}
return (0);
}
/*
* Stateless read - os internal file pointer is not updated.
*
* fp - pointer to file (pipe, socket, etc) to read from
* buf - buffer to write
* count - # of bytes to write
* off - file offset to read from (only valid for seekable types)
* resid - pointer to count of unwritten bytes (if short write)
*
* Returns 0 on success errno on failure.
*/
int
zfs_file_pread(zfs_file_t *fp, void *buf, size_t count, loff_t off,
ssize_t *resid)
{
ssize_t rc;
rc = pread64(fp->f_fd, buf, count, off);
if (rc < 0) {
#ifdef __linux__
/*
* Under Linux, this most likely means an alignment issue
* (memory or disk) due to O_DIRECT, so we abort() in order to
* catch the offender.
*/
if (errno == EINVAL)
abort();
#endif
return (errno);
}
if (fp->f_dump_fd != -1) {
int status;
status = pwrite64(fp->f_dump_fd, buf, rc, off);
ASSERT(status != -1);
}
if (resid) {
*resid = count - rc;
} else if (rc != count) {
return (EIO);
}
return (0);
}
/*
* lseek - set / get file pointer
*
* fp - pointer to file (pipe, socket, etc) to read from
* offp - value to seek to, returns current value plus passed offset
* whence - see man pages for standard lseek whence values
*
* Returns 0 on success errno on failure (ESPIPE for non seekable types)
*/
int
zfs_file_seek(zfs_file_t *fp, loff_t *offp, int whence)
{
loff_t rc;
rc = lseek(fp->f_fd, *offp, whence);
if (rc < 0)
return (errno);
*offp = rc;
return (0);
}
/*
* Get file attributes
*
* filp - file pointer
* zfattr - pointer to file attr structure
*
* Currently only used for fetching size and file mode
*
* Returns 0 on success or error code of underlying getattr call on failure.
*/
int
zfs_file_getattr(zfs_file_t *fp, zfs_file_attr_t *zfattr)
{
struct stat64 st;
if (fstat64_blk(fp->f_fd, &st) == -1)
return (errno);
zfattr->zfa_size = st.st_size;
zfattr->zfa_mode = st.st_mode;
return (0);
}
/*
* Sync file to disk
*
* filp - file pointer
* flags - O_SYNC and or O_DSYNC
*
* Returns 0 on success or error code of underlying sync call on failure.
*/
int
zfs_file_fsync(zfs_file_t *fp, int flags)
{
int rc;
rc = fsync(fp->f_fd);
if (rc < 0)
return (errno);
return (0);
}
/*
* fallocate - allocate or free space on disk
*
* fp - file pointer
* mode (non-standard options for hole punching etc)
* offset - offset to start allocating or freeing from
* len - length to free / allocate
*
* OPTIONAL
*/
int
zfs_file_fallocate(zfs_file_t *fp, int mode, loff_t offset, loff_t len)
{
#ifdef __linux__
return (fallocate(fp->f_fd, mode, offset, len));
#else
return (EOPNOTSUPP);
#endif
}
/*
* Request current file pointer offset
*
* fp - pointer to file
*
* Returns current file offset.
*/
loff_t
zfs_file_off(zfs_file_t *fp)
{
return (lseek(fp->f_fd, SEEK_CUR, 0));
}
/*
* unlink file
*
* path - fully qualified file path
*
* Returns 0 on success.
*
* OPTIONAL
*/
int
zfs_file_unlink(const char *path)
{
return (remove(path));
}
/*
* Get reference to file pointer
*
* fd - input file descriptor
* fpp - pointer to file pointer
*
* Returns 0 on success EBADF on failure.
* Unsupported in user space.
*/
int
zfs_file_get(int fd, zfs_file_t **fpp)
{
abort();
return (EOPNOTSUPP);
}
/*
* Drop reference to file pointer
*
* fd - input file descriptor
*
* Unsupported in user space.
*/
void
zfs_file_put(int fd)
{
abort();
}