freebsd-nq/sys/compat/linprocfs/linprocfs.c

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/*
* Copyright (c) 2000 Dag-Erling Co<EFBFBD>dan Sm<EFBFBD>rgrav
* Copyright (c) 1999 Pierre Beyssac
* Copyright (c) 1993 Jan-Simon Pendry
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)procfs_status.c 8.4 (Berkeley) 6/15/94
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/blist.h>
#include <sys/dkstat.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sbuf.h>
#include <sys/systm.h>
#include <sys/tty.h>
#include <sys/vnode.h>
#include <sys/jail.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_param.h>
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#include <vm/vm_object.h>
#include <vm/vm_zone.h>
#include <vm/swap_pager.h>
#include <sys/exec.h>
#include <sys/user.h>
#include <sys/vmmeter.h>
#include <machine/clock.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <compat/linux/linux_mib.h>
#include <compat/linprocfs/linprocfs.h>
/*
* Various conversion macros
*/
#define T2J(x) (((x) * 100) / (stathz ? stathz : hz)) /* ticks to jiffies */
#define T2S(x) ((x) / (stathz ? stathz : hz)) /* ticks to seconds */
#define B2K(x) ((x) >> 10) /* bytes to kbytes */
#define B2P(x) ((x) >> PAGE_SHIFT) /* bytes to pages */
#define P2B(x) ((x) << PAGE_SHIFT) /* pages to bytes */
#define P2K(x) ((x) << (PAGE_SHIFT - 10)) /* pages to kbytes */
int
linprocfs_domeminfo(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct sbuf sb;
char *ps;
int r, xlen;
unsigned long memtotal; /* total memory in bytes */
unsigned long memused; /* used memory in bytes */
unsigned long memfree; /* free memory in bytes */
unsigned long memshared; /* shared memory ??? */
unsigned long buffers, cached; /* buffer / cache memory ??? */
unsigned long swaptotal; /* total swap space in bytes */
unsigned long swapused; /* used swap space in bytes */
unsigned long swapfree; /* free swap space in bytes */
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vm_object_t object;
if (uio->uio_rw != UIO_READ)
return (EOPNOTSUPP);
memtotal = physmem * PAGE_SIZE;
/*
* The correct thing here would be:
*
memfree = cnt.v_free_count * PAGE_SIZE;
memused = memtotal - memfree;
*
* but it might mislead linux binaries into thinking there
* is very little memory left, so we cheat and tell them that
* all memory that isn't wired down is free.
*/
memused = cnt.v_wire_count * PAGE_SIZE;
memfree = memtotal - memused;
if (swapblist == NULL) {
swaptotal = 0;
swapfree = 0;
} else {
swaptotal = swapblist->bl_blocks * 1024; /* XXX why 1024? */
swapfree = swapblist->bl_root->u.bmu_avail * PAGE_SIZE;
}
swapused = swaptotal - swapfree;
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memshared = 0;
TAILQ_FOREACH(object, &vm_object_list, object_list)
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if (object->shadow_count > 1)
memshared += object->resident_page_count;
memshared *= PAGE_SIZE;
/*
* We'd love to be able to write:
*
buffers = bufspace;
*
* but bufspace is internal to vfs_bio.c and we don't feel
* like unstaticizing it just for linprocfs's sake.
*/
buffers = 0;
cached = cnt.v_cache_count * PAGE_SIZE;
sbuf_new(&sb, NULL, 512, 0);
sbuf_printf(&sb,
" total: used: free: shared: buffers: cached:\n"
"Mem: %lu %lu %lu %lu %lu %lu\n"
"Swap: %lu %lu %lu\n"
"MemTotal: %9lu kB\n"
"MemFree: %9lu kB\n"
"MemShared:%9lu kB\n"
"Buffers: %9lu kB\n"
"Cached: %9lu kB\n"
"SwapTotal:%9lu kB\n"
"SwapFree: %9lu kB\n",
memtotal, memused, memfree, memshared, buffers, cached,
swaptotal, swapused, swapfree,
B2K(memtotal), B2K(memfree),
B2K(memshared), B2K(buffers), B2K(cached),
B2K(swaptotal), B2K(swapfree));
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}
int
linprocfs_docpuinfo(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct sbuf sb;
char *ps;
int r, xlen;
int class, i, fqmhz, fqkhz;
/*
* We default the flags to include all non-conflicting flags,
* and the Intel versions of conflicting flags.
*/
static char *flags[] = {
"fpu", "vme", "de", "pse", "tsc",
"msr", "pae", "mce", "cx8", "apic",
"sep", "sep", "mtrr", "pge", "mca",
"cmov", "pat", "pse36", "pn", "b19",
"b20", "b21", "mmxext", "mmx", "fxsr",
"xmm", "b26", "b27", "b28", "b29",
"3dnowext", "3dnow"
};
if (uio->uio_rw != UIO_READ)
return (EOPNOTSUPP);
switch (cpu_class) {
case CPUCLASS_286:
class = 2;
break;
case CPUCLASS_386:
class = 3;
break;
case CPUCLASS_486:
class = 4;
break;
case CPUCLASS_586:
class = 5;
break;
case CPUCLASS_686:
class = 6;
break;
default:
class = 0;
break;
}
sbuf_new(&sb, NULL, 512, 0);
sbuf_printf(&sb,
"processor\t: %d\n"
"vendor_id\t: %.20s\n"
"cpu family\t: %d\n"
"model\t\t: %d\n"
"stepping\t: %d\n",
0, cpu_vendor, class, cpu, cpu_id & 0xf);
sbuf_cat(&sb,
"flags\t\t:");
if (!strcmp(cpu_vendor, "AuthenticAMD") && (class < 6)) {
flags[16] = "fcmov";
} else if (!strcmp(cpu_vendor, "CyrixInstead")) {
flags[24] = "cxmmx";
}
for (i = 0; i < 32; i++)
if (cpu_feature & (1 << i))
sbuf_printf(&sb, " %s", flags[i]);
sbuf_cat(&sb, "\n");
if (class >= 5) {
fqmhz = (tsc_freq + 4999) / 1000000;
fqkhz = ((tsc_freq + 4999) / 10000) % 100;
sbuf_printf(&sb,
"cpu MHz\t\t: %d.%02d\n"
"bogomips\t: %d.%02d\n",
fqmhz, fqkhz, fqmhz, fqkhz);
}
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}
int
linprocfs_dostat(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct sbuf sb;
char *ps;
int r, xlen;
sbuf_new(&sb, NULL, 512, 0);
sbuf_printf(&sb,
"cpu %ld %ld %ld %ld\n"
"disk 0 0 0 0\n"
"page %u %u\n"
"swap %u %u\n"
"intr %u\n"
"ctxt %u\n"
"btime %ld\n",
T2J(cp_time[CP_USER]),
T2J(cp_time[CP_NICE]),
T2J(cp_time[CP_SYS] /*+ cp_time[CP_INTR]*/),
T2J(cp_time[CP_IDLE]),
cnt.v_vnodepgsin,
cnt.v_vnodepgsout,
cnt.v_swappgsin,
cnt.v_swappgsout,
cnt.v_intr,
cnt.v_swtch,
boottime.tv_sec);
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}
int
linprocfs_douptime(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct sbuf sb;
char *ps;
int r, xlen;
struct timeval tv;
getmicrouptime(&tv);
sbuf_new(&sb, NULL, 64, 0);
sbuf_printf(&sb, "%ld.%02ld %ld.%02ld\n",
tv.tv_sec, tv.tv_usec / 10000,
T2S(cp_time[CP_IDLE]), T2J(cp_time[CP_IDLE]) % 100);
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}
int
linprocfs_doversion(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct sbuf sb;
char *ps;
int r, xlen;
sbuf_new(&sb, NULL, 128, 0);
sbuf_printf(&sb,
"%s version %s (des@freebsd.org) (gcc version " __VERSION__ ")"
" #4 Sun Dec 18 04:30:00 CET 1977\n",
linux_get_osname(curp),
linux_get_osrelease(curp));
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}
int
linprocfs_doprocstat(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct kinfo_proc kp;
struct sbuf sb;
char *ps;
int r, xlen;
fill_kinfo_proc(p, &kp);
sbuf_new(&sb, NULL, 1024, 0);
sbuf_printf(&sb, "%d", p->p_pid);
#define PS_ADD(name, fmt, arg) sbuf_printf(&sb, " " fmt, arg)
PS_ADD("comm", "(%s)", p->p_comm);
PS_ADD("statr", "%c", '0'); /* XXX */
PROC_LOCK(p);
PS_ADD("ppid", "%d", p->p_pptr ? p->p_pptr->p_pid : 0);
PROC_UNLOCK(p);
PS_ADD("pgrp", "%d", p->p_pgid);
PS_ADD("session", "%d", p->p_session->s_sid);
PS_ADD("tty", "%d", 0); /* XXX */
PS_ADD("tpgid", "%d", 0); /* XXX */
PS_ADD("flags", "%u", 0); /* XXX */
PS_ADD("minflt", "%u", 0); /* XXX */
PS_ADD("cminflt", "%u", 0); /* XXX */
PS_ADD("majflt", "%u", 0); /* XXX */
PS_ADD("cminflt", "%u", 0); /* XXX */
PS_ADD("utime", "%d", 0); /* XXX */
PS_ADD("stime", "%d", 0); /* XXX */
PS_ADD("cutime", "%d", 0); /* XXX */
PS_ADD("cstime", "%d", 0); /* XXX */
PS_ADD("counter", "%d", 0); /* XXX */
PS_ADD("priority", "%d", 0); /* XXX */
PS_ADD("timeout", "%u", 0); /* XXX */
PS_ADD("itrealvalue", "%u", 0); /* XXX */
PS_ADD("starttime", "%d", 0); /* XXX */
PS_ADD("vsize", "%u", kp.ki_size);
PS_ADD("rss", "%u", P2K(kp.ki_rssize));
PS_ADD("rlim", "%u", 0); /* XXX */
PS_ADD("startcode", "%u", (unsigned)0);
PS_ADD("endcode", "%u", 0); /* XXX */
PS_ADD("startstack", "%u", 0); /* XXX */
PS_ADD("esp", "%u", 0); /* XXX */
PS_ADD("eip", "%u", 0); /* XXX */
PS_ADD("signal", "%d", 0); /* XXX */
PS_ADD("blocked", "%d", 0); /* XXX */
PS_ADD("sigignore", "%d", 0); /* XXX */
PS_ADD("sigcatch", "%d", 0); /* XXX */
PS_ADD("wchan", "%u", 0); /* XXX */
PS_ADD("nswap", "%lu", (long unsigned)0); /* XXX */
PS_ADD("cnswap", "%lu", (long unsigned)0); /* XXX */
PS_ADD("exitsignal", "%d", 0); /* XXX */
PS_ADD("processor", "%d", 0); /* XXX */
#undef PS_ADD
sbuf_putc(&sb, '\n');
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}
/*
* Map process state to descriptive letter. Note that this does not
* quite correspond to what Linux outputs, but it's close enough.
*/
static char *state_str[] = {
"? (unknown)",
"I (idle)",
"R (running)",
"S (sleeping)",
"T (stopped)",
"Z (zombie)",
"W (waiting)",
"M (mutex)"
};
int
linprocfs_doprocstatus(curp, p, pfs, uio)
struct proc *curp;
struct proc *p;
struct pfsnode *pfs;
struct uio *uio;
{
struct kinfo_proc kp;
struct sbuf sb;
char *ps;
char *state;
int i, r, xlen;
segsz_t lsize;
sbuf_new(&sb, NULL, 1024, 0);
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_lock_spin(&sched_lock);
if (p->p_stat > sizeof state_str / sizeof *state_str)
state = state_str[0];
else
state = state_str[(int)p->p_stat];
Change and clean the mutex lock interface. mtx_enter(lock, type) becomes: mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks) mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized) similarily, for releasing a lock, we now have: mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN. We change the caller interface for the two different types of locks because the semantics are entirely different for each case, and this makes it explicitly clear and, at the same time, it rids us of the extra `type' argument. The enter->lock and exit->unlock change has been made with the idea that we're "locking data" and not "entering locked code" in mind. Further, remove all additional "flags" previously passed to the lock acquire/release routines with the exception of two: MTX_QUIET and MTX_NOSWITCH The functionality of these flags is preserved and they can be passed to the lock/unlock routines by calling the corresponding wrappers: mtx_{lock, unlock}_flags(lock, flag(s)) and mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN locks, respectively. Re-inline some lock acq/rel code; in the sleep lock case, we only inline the _obtain_lock()s in order to ensure that the inlined code fits into a cache line. In the spin lock case, we inline recursion and actually only perform a function call if we need to spin. This change has been made with the idea that we generally tend to avoid spin locks and that also the spin locks that we do have and are heavily used (i.e. sched_lock) do recurse, and therefore in an effort to reduce function call overhead for some architectures (such as alpha), we inline recursion for this case. Create a new malloc type for the witness code and retire from using the M_DEV type. The new type is called M_WITNESS and is only declared if WITNESS is enabled. Begin cleaning up some machdep/mutex.h code - specifically updated the "optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently need those. Finally, caught up to the interface changes in all sys code. Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
mtx_unlock_spin(&sched_lock);
fill_kinfo_proc(p, &kp);
sbuf_printf(&sb, "Name:\t%s\n", p->p_comm); /* XXX escape */
sbuf_printf(&sb, "State:\t%s\n", state);
/*
* Credentials
*/
sbuf_printf(&sb, "Pid:\t%d\n", p->p_pid);
PROC_LOCK(p);
sbuf_printf(&sb, "PPid:\t%d\n", p->p_pptr ?
p->p_pptr->p_pid : 0);
sbuf_printf(&sb, "Uid:\t%d %d %d %d\n", p->p_cred->p_ruid,
p->p_ucred->cr_uid,
p->p_cred->p_svuid,
/* FreeBSD doesn't have fsuid */
p->p_ucred->cr_uid);
sbuf_printf(&sb, "Gid:\t%d %d %d %d\n", p->p_cred->p_rgid,
p->p_ucred->cr_gid,
p->p_cred->p_svgid,
/* FreeBSD doesn't have fsgid */
p->p_ucred->cr_gid);
sbuf_cat(&sb, "Groups:\t");
for (i = 0; i < p->p_ucred->cr_ngroups; i++)
sbuf_printf(&sb, "%d ", p->p_ucred->cr_groups[i]);
PROC_UNLOCK(p);
sbuf_putc(&sb, '\n');
/*
* Memory
*
* While our approximation of VmLib may not be accurate (I
* don't know of a simple way to verify it, and I'm not sure
* it has much meaning anyway), I believe it's good enough.
*
* The same code that could (I think) accurately compute VmLib
* could also compute VmLck, but I don't really care enough to
* implement it. Submissions are welcome.
*/
sbuf_printf(&sb, "VmSize:\t%8u kB\n", B2K(kp.ki_size));
sbuf_printf(&sb, "VmLck:\t%8u kB\n", P2K(0)); /* XXX */
sbuf_printf(&sb, "VmRss:\t%8u kB\n", P2K(kp.ki_rssize));
sbuf_printf(&sb, "VmData:\t%8u kB\n", P2K(kp.ki_dsize));
sbuf_printf(&sb, "VmStk:\t%8u kB\n", P2K(kp.ki_ssize));
sbuf_printf(&sb, "VmExe:\t%8u kB\n", P2K(kp.ki_tsize));
lsize = B2P(kp.ki_size) - kp.ki_dsize -
kp.ki_ssize - kp.ki_tsize - 1;
sbuf_printf(&sb, "VmLib:\t%8u kB\n", P2K(lsize));
/*
* Signal masks
*
* We support up to 128 signals, while Linux supports 32,
* but we only define 32 (the same 32 as Linux, to boot), so
* just show the lower 32 bits of each mask. XXX hack.
*
* NB: on certain platforms (Sparc at least) Linux actually
* supports 64 signals, but this code is a long way from
* running on anything but i386, so ignore that for now.
*/
PROC_LOCK(p);
sbuf_printf(&sb, "SigPnd:\t%08x\n", p->p_siglist.__bits[0]);
/*
* I can't seem to find out where the signal mask is in
* relation to struct proc, so SigBlk is left unimplemented.
*/
sbuf_printf(&sb, "SigBlk:\t%08x\n", 0); /* XXX */
sbuf_printf(&sb, "SigIgn:\t%08x\n", p->p_sigignore.__bits[0]);
sbuf_printf(&sb, "SigCgt:\t%08x\n", p->p_sigcatch.__bits[0]);
PROC_UNLOCK(p);
/*
* Linux also prints the capability masks, but we don't have
* capabilities yet, and when we do get them they're likely to
* be meaningless to Linux programs, so we lie. XXX
*/
sbuf_printf(&sb, "CapInh:\t%016x\n", 0);
sbuf_printf(&sb, "CapPrm:\t%016x\n", 0);
sbuf_printf(&sb, "CapEff:\t%016x\n", 0);
sbuf_finish(&sb);
ps = sbuf_data(&sb) + uio->uio_offset;
xlen = sbuf_len(&sb) - uio->uio_offset;
xlen = imin(xlen, uio->uio_resid);
r = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio));
sbuf_delete(&sb);
return r;
}