mirror_zfs/module/os/linux/spl/spl-proc.c
Rob Norris 2633075e09 Linux 6.11: avoid passing "end" sentinel to register_sysctl()
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Closes #16400
2024-08-13 17:47:22 -07:00

808 lines
19 KiB
C

/*
* Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
* Copyright (C) 2007 The Regents of the University of California.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* UCRL-CODE-235197
*
* This file is part of the SPL, Solaris Porting Layer.
*
* The SPL 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 2 of the License, or (at your
* option) any later version.
*
* The SPL 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 the SPL. If not, see <http://www.gnu.org/licenses/>.
*
* Solaris Porting Layer (SPL) Proc Implementation.
*/
/*
* Copyright (c) 2024, Rob Norris <robn@despairlabs.com>
*/
#include <sys/systeminfo.h>
#include <sys/kstat.h>
#include <sys/kmem.h>
#include <sys/kmem_cache.h>
#include <sys/vmem.h>
#include <sys/taskq.h>
#include <sys/proc.h>
#include <linux/ctype.h>
#include <linux/kmod.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/version.h>
#include "zfs_gitrev.h"
#if defined(CONSTIFY_PLUGIN) && LINUX_VERSION_CODE >= KERNEL_VERSION(3, 8, 0)
typedef struct ctl_table __no_const spl_ctl_table;
#else
typedef struct ctl_table spl_ctl_table;
#endif
#ifdef HAVE_PROC_HANDLER_CTL_TABLE_CONST
#define CONST_CTL_TABLE const struct ctl_table
#else
#define CONST_CTL_TABLE struct ctl_table
#endif
static unsigned long table_min = 0;
static unsigned long table_max = ~0;
static struct ctl_table_header *spl_header = NULL;
#ifndef HAVE_REGISTER_SYSCTL_TABLE
static struct ctl_table_header *spl_kmem = NULL;
static struct ctl_table_header *spl_kstat = NULL;
#endif
static struct proc_dir_entry *proc_spl = NULL;
static struct proc_dir_entry *proc_spl_kmem = NULL;
static struct proc_dir_entry *proc_spl_kmem_slab = NULL;
static struct proc_dir_entry *proc_spl_taskq_all = NULL;
static struct proc_dir_entry *proc_spl_taskq = NULL;
struct proc_dir_entry *proc_spl_kstat = NULL;
#ifdef DEBUG_KMEM
static int
proc_domemused(CONST_CTL_TABLE *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int rc = 0;
unsigned long val;
spl_ctl_table dummy = *table;
dummy.data = &val;
dummy.proc_handler = &proc_dointvec;
dummy.extra1 = &table_min;
dummy.extra2 = &table_max;
if (write) {
*ppos += *lenp;
} else {
#ifdef HAVE_ATOMIC64_T
val = atomic64_read((atomic64_t *)table->data);
#else
val = atomic_read((atomic_t *)table->data);
#endif /* HAVE_ATOMIC64_T */
rc = proc_doulongvec_minmax(&dummy, write, buffer, lenp, ppos);
}
return (rc);
}
#endif /* DEBUG_KMEM */
static int
proc_doslab(CONST_CTL_TABLE *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int rc = 0;
unsigned long val = 0, mask;
spl_ctl_table dummy = *table;
spl_kmem_cache_t *skc = NULL;
dummy.data = &val;
dummy.proc_handler = &proc_dointvec;
dummy.extra1 = &table_min;
dummy.extra2 = &table_max;
if (write) {
*ppos += *lenp;
} else {
down_read(&spl_kmem_cache_sem);
mask = (unsigned long)table->data;
list_for_each_entry(skc, &spl_kmem_cache_list, skc_list) {
/* Only use slabs of the correct kmem/vmem type */
if (!(skc->skc_flags & mask))
continue;
/* Sum the specified field for selected slabs */
switch (mask & (KMC_TOTAL | KMC_ALLOC | KMC_MAX)) {
case KMC_TOTAL:
val += skc->skc_slab_size * skc->skc_slab_total;
break;
case KMC_ALLOC:
val += skc->skc_obj_size * skc->skc_obj_alloc;
break;
case KMC_MAX:
val += skc->skc_obj_size * skc->skc_obj_max;
break;
}
}
up_read(&spl_kmem_cache_sem);
rc = proc_doulongvec_minmax(&dummy, write, buffer, lenp, ppos);
}
return (rc);
}
static int
proc_dohostid(CONST_CTL_TABLE *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
char *end, str[32];
unsigned long hid;
spl_ctl_table dummy = *table;
dummy.data = str;
dummy.maxlen = sizeof (str) - 1;
if (!write)
snprintf(str, sizeof (str), "%lx",
(unsigned long) zone_get_hostid(NULL));
/* always returns 0 */
proc_dostring(&dummy, write, buffer, lenp, ppos);
if (write) {
/*
* We can't use proc_doulongvec_minmax() in the write
* case here because hostid, while a hex value, has no
* leading 0x, which confuses the helper function.
*/
hid = simple_strtoul(str, &end, 16);
if (str == end)
return (-EINVAL);
spl_hostid = hid;
}
return (0);
}
static void
taskq_seq_show_headers(struct seq_file *f)
{
seq_printf(f, "%-25s %5s %5s %5s %5s %5s %5s %12s %5s %10s\n",
"taskq", "act", "nthr", "spwn", "maxt", "pri",
"mina", "maxa", "cura", "flags");
}
/* indices into the lheads array below */
#define LHEAD_PEND 0
#define LHEAD_PRIO 1
#define LHEAD_DELAY 2
#define LHEAD_WAIT 3
#define LHEAD_ACTIVE 4
#define LHEAD_SIZE 5
static unsigned int spl_max_show_tasks = 512;
/* CSTYLED */
module_param(spl_max_show_tasks, uint, 0644);
MODULE_PARM_DESC(spl_max_show_tasks, "Max number of tasks shown in taskq proc");
static int
taskq_seq_show_impl(struct seq_file *f, void *p, boolean_t allflag)
{
taskq_t *tq = p;
taskq_thread_t *tqt = NULL;
spl_wait_queue_entry_t *wq;
struct task_struct *tsk;
taskq_ent_t *tqe;
char name[100];
struct list_head *lheads[LHEAD_SIZE], *lh;
static char *list_names[LHEAD_SIZE] =
{"pend", "prio", "delay", "wait", "active" };
int i, j, have_lheads = 0;
unsigned long wflags, flags;
spin_lock_irqsave_nested(&tq->tq_lock, flags, tq->tq_lock_class);
spin_lock_irqsave(&tq->tq_wait_waitq.lock, wflags);
/* get the various lists and check whether they're empty */
lheads[LHEAD_PEND] = &tq->tq_pend_list;
lheads[LHEAD_PRIO] = &tq->tq_prio_list;
lheads[LHEAD_DELAY] = &tq->tq_delay_list;
#ifdef HAVE_WAIT_QUEUE_HEAD_ENTRY
lheads[LHEAD_WAIT] = &tq->tq_wait_waitq.head;
#else
lheads[LHEAD_WAIT] = &tq->tq_wait_waitq.task_list;
#endif
lheads[LHEAD_ACTIVE] = &tq->tq_active_list;
for (i = 0; i < LHEAD_SIZE; ++i) {
if (list_empty(lheads[i]))
lheads[i] = NULL;
else
++have_lheads;
}
/* early return in non-"all" mode if lists are all empty */
if (!allflag && !have_lheads) {
spin_unlock_irqrestore(&tq->tq_wait_waitq.lock, wflags);
spin_unlock_irqrestore(&tq->tq_lock, flags);
return (0);
}
/* unlock the waitq quickly */
if (!lheads[LHEAD_WAIT])
spin_unlock_irqrestore(&tq->tq_wait_waitq.lock, wflags);
/* show the base taskq contents */
snprintf(name, sizeof (name), "%s/%d", tq->tq_name, tq->tq_instance);
seq_printf(f, "%-25s ", name);
seq_printf(f, "%5d %5d %5d %5d %5d %5d %12d %5d %10x\n",
tq->tq_nactive, tq->tq_nthreads, tq->tq_nspawn,
tq->tq_maxthreads, tq->tq_pri, tq->tq_minalloc, tq->tq_maxalloc,
tq->tq_nalloc, tq->tq_flags);
/* show the active list */
if (lheads[LHEAD_ACTIVE]) {
j = 0;
list_for_each_entry(tqt, &tq->tq_active_list, tqt_active_list) {
if (j == 0)
seq_printf(f, "\t%s:",
list_names[LHEAD_ACTIVE]);
else if (j == 2) {
seq_printf(f, "\n\t ");
j = 0;
}
seq_printf(f, " [%d]%pf(%ps)",
tqt->tqt_thread->pid,
tqt->tqt_task->tqent_func,
tqt->tqt_task->tqent_arg);
++j;
}
seq_printf(f, "\n");
}
for (i = LHEAD_PEND; i <= LHEAD_WAIT; ++i)
if (lheads[i]) {
j = 0;
list_for_each(lh, lheads[i]) {
if (spl_max_show_tasks != 0 &&
j >= spl_max_show_tasks) {
seq_printf(f, "\n\t(truncated)");
break;
}
/* show the wait waitq list */
if (i == LHEAD_WAIT) {
#ifdef HAVE_WAIT_QUEUE_HEAD_ENTRY
wq = list_entry(lh,
spl_wait_queue_entry_t, entry);
#else
wq = list_entry(lh,
spl_wait_queue_entry_t, task_list);
#endif
if (j == 0)
seq_printf(f, "\t%s:",
list_names[i]);
else if (j % 8 == 0)
seq_printf(f, "\n\t ");
tsk = wq->private;
seq_printf(f, " %d", tsk->pid);
/* pend, prio and delay lists */
} else {
tqe = list_entry(lh, taskq_ent_t,
tqent_list);
if (j == 0)
seq_printf(f, "\t%s:",
list_names[i]);
else if (j % 2 == 0)
seq_printf(f, "\n\t ");
seq_printf(f, " %pf(%ps)",
tqe->tqent_func,
tqe->tqent_arg);
}
++j;
}
seq_printf(f, "\n");
}
if (lheads[LHEAD_WAIT])
spin_unlock_irqrestore(&tq->tq_wait_waitq.lock, wflags);
spin_unlock_irqrestore(&tq->tq_lock, flags);
return (0);
}
static int
taskq_all_seq_show(struct seq_file *f, void *p)
{
return (taskq_seq_show_impl(f, p, B_TRUE));
}
static int
taskq_seq_show(struct seq_file *f, void *p)
{
return (taskq_seq_show_impl(f, p, B_FALSE));
}
static void *
taskq_seq_start(struct seq_file *f, loff_t *pos)
{
struct list_head *p;
loff_t n = *pos;
down_read(&tq_list_sem);
if (!n)
taskq_seq_show_headers(f);
p = tq_list.next;
while (n--) {
p = p->next;
if (p == &tq_list)
return (NULL);
}
return (list_entry(p, taskq_t, tq_taskqs));
}
static void *
taskq_seq_next(struct seq_file *f, void *p, loff_t *pos)
{
taskq_t *tq = p;
++*pos;
return ((tq->tq_taskqs.next == &tq_list) ?
NULL : list_entry(tq->tq_taskqs.next, taskq_t, tq_taskqs));
}
static void
slab_seq_show_headers(struct seq_file *f)
{
seq_printf(f,
"--------------------- cache ----------"
"--------------------------------------------- "
"----- slab ------ "
"---- object ----- "
"--- emergency ---\n");
seq_printf(f,
"name "
" flags size alloc slabsize objsize "
"total alloc max "
"total alloc max "
"dlock alloc max\n");
}
static int
slab_seq_show(struct seq_file *f, void *p)
{
spl_kmem_cache_t *skc = p;
ASSERT(skc->skc_magic == SKC_MAGIC);
if (skc->skc_flags & KMC_SLAB) {
/*
* This cache is backed by a generic Linux kmem cache which
* has its own accounting. For these caches we only track
* the number of active allocated objects that exist within
* the underlying Linux slabs. For the overall statistics of
* the underlying Linux cache please refer to /proc/slabinfo.
*/
spin_lock(&skc->skc_lock);
uint64_t objs_allocated =
percpu_counter_sum(&skc->skc_linux_alloc);
seq_printf(f, "%-36s ", skc->skc_name);
seq_printf(f, "0x%05lx %9s %9lu %8s %8u "
"%5s %5s %5s %5s %5lu %5s %5s %5s %5s\n",
(long unsigned)skc->skc_flags,
"-",
(long unsigned)(skc->skc_obj_size * objs_allocated),
"-",
(unsigned)skc->skc_obj_size,
"-", "-", "-", "-",
(long unsigned)objs_allocated,
"-", "-", "-", "-");
spin_unlock(&skc->skc_lock);
return (0);
}
spin_lock(&skc->skc_lock);
seq_printf(f, "%-36s ", skc->skc_name);
seq_printf(f, "0x%05lx %9lu %9lu %8u %8u "
"%5lu %5lu %5lu %5lu %5lu %5lu %5lu %5lu %5lu\n",
(long unsigned)skc->skc_flags,
(long unsigned)(skc->skc_slab_size * skc->skc_slab_total),
(long unsigned)(skc->skc_obj_size * skc->skc_obj_alloc),
(unsigned)skc->skc_slab_size,
(unsigned)skc->skc_obj_size,
(long unsigned)skc->skc_slab_total,
(long unsigned)skc->skc_slab_alloc,
(long unsigned)skc->skc_slab_max,
(long unsigned)skc->skc_obj_total,
(long unsigned)skc->skc_obj_alloc,
(long unsigned)skc->skc_obj_max,
(long unsigned)skc->skc_obj_deadlock,
(long unsigned)skc->skc_obj_emergency,
(long unsigned)skc->skc_obj_emergency_max);
spin_unlock(&skc->skc_lock);
return (0);
}
static void *
slab_seq_start(struct seq_file *f, loff_t *pos)
{
struct list_head *p;
loff_t n = *pos;
down_read(&spl_kmem_cache_sem);
if (!n)
slab_seq_show_headers(f);
p = spl_kmem_cache_list.next;
while (n--) {
p = p->next;
if (p == &spl_kmem_cache_list)
return (NULL);
}
return (list_entry(p, spl_kmem_cache_t, skc_list));
}
static void *
slab_seq_next(struct seq_file *f, void *p, loff_t *pos)
{
spl_kmem_cache_t *skc = p;
++*pos;
return ((skc->skc_list.next == &spl_kmem_cache_list) ?
NULL : list_entry(skc->skc_list.next, spl_kmem_cache_t, skc_list));
}
static void
slab_seq_stop(struct seq_file *f, void *v)
{
up_read(&spl_kmem_cache_sem);
}
static const struct seq_operations slab_seq_ops = {
.show = slab_seq_show,
.start = slab_seq_start,
.next = slab_seq_next,
.stop = slab_seq_stop,
};
static int
proc_slab_open(struct inode *inode, struct file *filp)
{
return (seq_open(filp, &slab_seq_ops));
}
static const kstat_proc_op_t proc_slab_operations = {
#ifdef HAVE_PROC_OPS_STRUCT
.proc_open = proc_slab_open,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = seq_release,
#else
.open = proc_slab_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
#endif
};
static void
taskq_seq_stop(struct seq_file *f, void *v)
{
up_read(&tq_list_sem);
}
static const struct seq_operations taskq_all_seq_ops = {
.show = taskq_all_seq_show,
.start = taskq_seq_start,
.next = taskq_seq_next,
.stop = taskq_seq_stop,
};
static const struct seq_operations taskq_seq_ops = {
.show = taskq_seq_show,
.start = taskq_seq_start,
.next = taskq_seq_next,
.stop = taskq_seq_stop,
};
static int
proc_taskq_all_open(struct inode *inode, struct file *filp)
{
return (seq_open(filp, &taskq_all_seq_ops));
}
static int
proc_taskq_open(struct inode *inode, struct file *filp)
{
return (seq_open(filp, &taskq_seq_ops));
}
static const kstat_proc_op_t proc_taskq_all_operations = {
#ifdef HAVE_PROC_OPS_STRUCT
.proc_open = proc_taskq_all_open,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = seq_release,
#else
.open = proc_taskq_all_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
#endif
};
static const kstat_proc_op_t proc_taskq_operations = {
#ifdef HAVE_PROC_OPS_STRUCT
.proc_open = proc_taskq_open,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = seq_release,
#else
.open = proc_taskq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
#endif
};
static struct ctl_table spl_kmem_table[] = {
#ifdef DEBUG_KMEM
{
.procname = "kmem_used",
.data = &kmem_alloc_used,
#ifdef HAVE_ATOMIC64_T
.maxlen = sizeof (atomic64_t),
#else
.maxlen = sizeof (atomic_t),
#endif /* HAVE_ATOMIC64_T */
.mode = 0444,
.proc_handler = &proc_domemused,
},
{
.procname = "kmem_max",
.data = &kmem_alloc_max,
.maxlen = sizeof (unsigned long),
.extra1 = &table_min,
.extra2 = &table_max,
.mode = 0444,
.proc_handler = &proc_doulongvec_minmax,
},
#endif /* DEBUG_KMEM */
{
.procname = "slab_kvmem_total",
.data = (void *)(KMC_KVMEM | KMC_TOTAL),
.maxlen = sizeof (unsigned long),
.extra1 = &table_min,
.extra2 = &table_max,
.mode = 0444,
.proc_handler = &proc_doslab,
},
{
.procname = "slab_kvmem_alloc",
.data = (void *)(KMC_KVMEM | KMC_ALLOC),
.maxlen = sizeof (unsigned long),
.extra1 = &table_min,
.extra2 = &table_max,
.mode = 0444,
.proc_handler = &proc_doslab,
},
{
.procname = "slab_kvmem_max",
.data = (void *)(KMC_KVMEM | KMC_MAX),
.maxlen = sizeof (unsigned long),
.extra1 = &table_min,
.extra2 = &table_max,
.mode = 0444,
.proc_handler = &proc_doslab,
},
{},
};
static struct ctl_table spl_kstat_table[] = {
{},
};
static struct ctl_table spl_table[] = {
/*
* NB No .strategy entries have been provided since
* sysctl(8) prefers to go via /proc for portability.
*/
{
.procname = "gitrev",
.data = (char *)ZFS_META_GITREV,
.maxlen = sizeof (ZFS_META_GITREV),
.mode = 0444,
.proc_handler = &proc_dostring,
},
{
.procname = "hostid",
.data = &spl_hostid,
.maxlen = sizeof (unsigned long),
.mode = 0644,
.proc_handler = &proc_dohostid,
},
#ifdef HAVE_REGISTER_SYSCTL_TABLE
{
.procname = "kmem",
.mode = 0555,
.child = spl_kmem_table,
},
{
.procname = "kstat",
.mode = 0555,
.child = spl_kstat_table,
},
#endif
{},
};
#ifdef HAVE_REGISTER_SYSCTL_TABLE
static struct ctl_table spl_dir[] = {
{
.procname = "spl",
.mode = 0555,
.child = spl_table,
},
{}
};
static struct ctl_table spl_root[] = {
{
.procname = "kernel",
.mode = 0555,
.child = spl_dir,
},
{}
};
#endif
static void spl_proc_cleanup(void)
{
remove_proc_entry("kstat", proc_spl);
remove_proc_entry("slab", proc_spl_kmem);
remove_proc_entry("kmem", proc_spl);
remove_proc_entry("taskq-all", proc_spl);
remove_proc_entry("taskq", proc_spl);
remove_proc_entry("spl", NULL);
#ifndef HAVE_REGISTER_SYSCTL_TABLE
if (spl_kstat) {
unregister_sysctl_table(spl_kstat);
spl_kstat = NULL;
}
if (spl_kmem) {
unregister_sysctl_table(spl_kmem);
spl_kmem = NULL;
}
#endif
if (spl_header) {
unregister_sysctl_table(spl_header);
spl_header = NULL;
}
}
#ifndef HAVE_REGISTER_SYSCTL_TABLE
/*
* Traditionally, struct ctl_table arrays have been terminated by an "empty"
* sentinel element (specifically, one with .procname == NULL).
*
* Linux 6.6 began migrating away from this, adding register_sysctl_sz() so
* that callers could provide the size directly, and redefining
* register_sysctl() to just call register_sysctl_sz() with the array size. It
* retained support for the terminating element so that existing callers would
* continue to work.
*
* Linux 6.11 removed support for the terminating element, instead interpreting
* it as a real malformed element, and rejecting it.
*
* In order to continue support older kernels, we retain the terminating
* sentinel element for our sysctl tables, but instead detect availability of
* register_sysctl_sz(). If it exists, we pass it the array size -1, stopping
* the kernel from trying to process the terminator. For pre-6.6 kernels that
* don't have register_sysctl_sz(), we just use register_sysctl(), which can
* handle the terminating element as it always has.
*/
#ifdef HAVE_REGISTER_SYSCTL_SZ
#define spl_proc_register_sysctl(p, t) \
register_sysctl_sz(p, t, ARRAY_SIZE(t)-1)
#else
#define spl_proc_register_sysctl(p, t) \
register_sysctl(p, t)
#endif
#endif
int
spl_proc_init(void)
{
int rc = 0;
#ifdef HAVE_REGISTER_SYSCTL_TABLE
spl_header = register_sysctl_table(spl_root);
if (spl_header == NULL)
return (-EUNATCH);
#else
spl_header = spl_proc_register_sysctl("kernel/spl", spl_table);
if (spl_header == NULL)
return (-EUNATCH);
spl_kmem = spl_proc_register_sysctl("kernel/spl/kmem", spl_kmem_table);
if (spl_kmem == NULL) {
rc = -EUNATCH;
goto out;
}
spl_kstat = spl_proc_register_sysctl("kernel/spl/kstat",
spl_kstat_table);
if (spl_kstat == NULL) {
rc = -EUNATCH;
goto out;
}
#endif
proc_spl = proc_mkdir("spl", NULL);
if (proc_spl == NULL) {
rc = -EUNATCH;
goto out;
}
proc_spl_taskq_all = proc_create_data("taskq-all", 0444, proc_spl,
&proc_taskq_all_operations, NULL);
if (proc_spl_taskq_all == NULL) {
rc = -EUNATCH;
goto out;
}
proc_spl_taskq = proc_create_data("taskq", 0444, proc_spl,
&proc_taskq_operations, NULL);
if (proc_spl_taskq == NULL) {
rc = -EUNATCH;
goto out;
}
proc_spl_kmem = proc_mkdir("kmem", proc_spl);
if (proc_spl_kmem == NULL) {
rc = -EUNATCH;
goto out;
}
proc_spl_kmem_slab = proc_create_data("slab", 0444, proc_spl_kmem,
&proc_slab_operations, NULL);
if (proc_spl_kmem_slab == NULL) {
rc = -EUNATCH;
goto out;
}
proc_spl_kstat = proc_mkdir("kstat", proc_spl);
if (proc_spl_kstat == NULL) {
rc = -EUNATCH;
goto out;
}
out:
if (rc)
spl_proc_cleanup();
return (rc);
}
void
spl_proc_fini(void)
{
spl_proc_cleanup();
}