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freebsd-skq/sys/fs/pseudofs/pseudofs_vnops.c
johalun 130c445ced pseudofs: Ignore unsupported commands in vop_setattr. 
Users of pseudofs (e.g. lindebugfs), should be able to receive
input from command line via commands like "echo 1 > /path/to/file".
Currently this fails because sh tries to truncate the file first and
vop_setattr returns not supported error for this. This patch simply
ignores the error and returns 0 instead.

Reviewed by:	imp (mentor), asomers
Approved by:	imp (mentor), asomers
MFC after:	1 week
Differential Revision: D20451
2019-05-28 20:54:59 +00:00

1065 lines
23 KiB
C
Raw Blame History

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2001 Dag-Erling Coïdan Smørgrav
* 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
* in this position and unchanged.
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_pseudofs.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/ctype.h>
#include <sys/dirent.h>
#include <sys/fcntl.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/sx.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <fs/pseudofs/pseudofs.h>
#include <fs/pseudofs/pseudofs_internal.h>
#define KASSERT_PN_IS_DIR(pn) \
KASSERT((pn)->pn_type == pfstype_root || \
(pn)->pn_type == pfstype_dir || \
(pn)->pn_type == pfstype_procdir, \
("%s(): VDIR vnode refers to non-directory pfs_node", __func__))
#define KASSERT_PN_IS_FILE(pn) \
KASSERT((pn)->pn_type == pfstype_file, \
("%s(): VREG vnode refers to non-file pfs_node", __func__))
#define KASSERT_PN_IS_LINK(pn) \
KASSERT((pn)->pn_type == pfstype_symlink, \
("%s(): VLNK vnode refers to non-link pfs_node", __func__))
/*
* Returns the fileno, adjusted for target pid
*/
static uint32_t
pn_fileno(struct pfs_node *pn, pid_t pid)
{
KASSERT(pn->pn_fileno > 0,
("%s(): no fileno allocated", __func__));
if (pid != NO_PID)
return (pn->pn_fileno * NO_PID + pid);
return (pn->pn_fileno);
}
/*
* Returns non-zero if given file is visible to given thread.
*/
static int
pfs_visible_proc(struct thread *td, struct pfs_node *pn, struct proc *proc)
{
int visible;
if (proc == NULL)
return (0);
PROC_LOCK_ASSERT(proc, MA_OWNED);
visible = ((proc->p_flag & P_WEXIT) == 0);
if (visible)
visible = (p_cansee(td, proc) == 0);
if (visible && pn->pn_vis != NULL)
visible = pn_vis(td, proc, pn);
if (!visible)
return (0);
return (1);
}
static int
pfs_visible(struct thread *td, struct pfs_node *pn, pid_t pid,
struct proc **p)
{
struct proc *proc;
PFS_TRACE(("%s (pid: %d, req: %d)",
pn->pn_name, pid, td->td_proc->p_pid));
if (p)
*p = NULL;
if (pid == NO_PID)
PFS_RETURN (1);
proc = pfind(pid);
if (proc == NULL)
PFS_RETURN (0);
if (pfs_visible_proc(td, pn, proc)) {
if (p)
*p = proc;
else
PROC_UNLOCK(proc);
PFS_RETURN (1);
}
PROC_UNLOCK(proc);
PFS_RETURN (0);
}
/*
* Verify permissions
*/
static int
pfs_access(struct vop_access_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct vattr vattr;
int error;
PFS_TRACE(("%s", pvd->pvd_pn->pn_name));
(void)pvd;
error = VOP_GETATTR(vn, &vattr, va->a_cred);
if (error)
PFS_RETURN (error);
error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid,
vattr.va_gid, va->a_accmode, va->a_cred, NULL);
PFS_RETURN (error);
}
/*
* Close a file or directory
*/
static int
pfs_close(struct vop_close_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
struct proc *proc;
int error;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
/*
* Do nothing unless this is the last close and the node has a
* last-close handler.
*/
if (vrefcnt(vn) > 1 || pn->pn_close == NULL)
PFS_RETURN (0);
if (pvd->pvd_pid != NO_PID) {
proc = pfind(pvd->pvd_pid);
} else {
proc = NULL;
}
error = pn_close(va->a_td, proc, pn);
if (proc != NULL)
PROC_UNLOCK(proc);
PFS_RETURN (error);
}
/*
* Get file attributes
*/
static int
pfs_getattr(struct vop_getattr_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
struct vattr *vap = va->a_vap;
struct proc *proc;
int error = 0;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
PFS_RETURN (ENOENT);
vap->va_type = vn->v_type;
vap->va_fileid = pn_fileno(pn, pvd->pvd_pid);
vap->va_flags = 0;
vap->va_blocksize = PAGE_SIZE;
vap->va_bytes = vap->va_size = 0;
vap->va_filerev = 0;
vap->va_fsid = vn->v_mount->mnt_stat.f_fsid.val[0];
vap->va_nlink = 1;
nanotime(&vap->va_ctime);
vap->va_atime = vap->va_mtime = vap->va_ctime;
switch (pn->pn_type) {
case pfstype_procdir:
case pfstype_root:
case pfstype_dir:
#if 0
pfs_lock(pn);
/* compute link count */
pfs_unlock(pn);
#endif
vap->va_mode = 0555;
break;
case pfstype_file:
case pfstype_symlink:
vap->va_mode = 0444;
break;
default:
printf("shouldn't be here!\n");
vap->va_mode = 0;
break;
}
if (proc != NULL) {
vap->va_uid = proc->p_ucred->cr_ruid;
vap->va_gid = proc->p_ucred->cr_rgid;
} else {
vap->va_uid = 0;
vap->va_gid = 0;
}
if (pn->pn_attr != NULL)
error = pn_attr(curthread, proc, pn, vap);
if(proc != NULL)
PROC_UNLOCK(proc);
PFS_RETURN (error);
}
/*
* Perform an ioctl
*/
static int
pfs_ioctl(struct vop_ioctl_args *va)
{
struct vnode *vn;
struct pfs_vdata *pvd;
struct pfs_node *pn;
struct proc *proc;
int error;
vn = va->a_vp;
vn_lock(vn, LK_SHARED | LK_RETRY);
if (vn->v_iflag & VI_DOOMED) {
VOP_UNLOCK(vn, 0);
return (EBADF);
}
pvd = vn->v_data;
pn = pvd->pvd_pn;
PFS_TRACE(("%s: %lx", pn->pn_name, va->a_command));
pfs_assert_not_owned(pn);
if (vn->v_type != VREG) {
VOP_UNLOCK(vn, 0);
PFS_RETURN (EINVAL);
}
KASSERT_PN_IS_FILE(pn);
if (pn->pn_ioctl == NULL) {
VOP_UNLOCK(vn, 0);
PFS_RETURN (ENOTTY);
}
/*
* This is necessary because process' privileges may
* have changed since the open() call.
*/
if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) {
VOP_UNLOCK(vn, 0);
PFS_RETURN (EIO);
}
error = pn_ioctl(curthread, proc, pn, va->a_command, va->a_data);
if (proc != NULL)
PROC_UNLOCK(proc);
VOP_UNLOCK(vn, 0);
PFS_RETURN (error);
}
/*
* Perform getextattr
*/
static int
pfs_getextattr(struct vop_getextattr_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
struct proc *proc;
int error;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
/*
* This is necessary because either process' privileges may
* have changed since the open() call.
*/
if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
PFS_RETURN (EIO);
if (pn->pn_getextattr == NULL)
error = EOPNOTSUPP;
else
error = pn_getextattr(curthread, proc, pn,
va->a_attrnamespace, va->a_name, va->a_uio,
va->a_size, va->a_cred);
if (proc != NULL)
PROC_UNLOCK(proc);
PFS_RETURN (error);
}
/*
* Convert a vnode to its component name
*/
static int
pfs_vptocnp(struct vop_vptocnp_args *ap)
{
struct vnode *vp = ap->a_vp;
struct vnode **dvp = ap->a_vpp;
struct pfs_vdata *pvd = vp->v_data;
struct pfs_node *pd = pvd->pvd_pn;
struct pfs_node *pn;
struct mount *mp;
char *buf = ap->a_buf;
int *buflen = ap->a_buflen;
char pidbuf[PFS_NAMELEN];
pid_t pid = pvd->pvd_pid;
int len, i, error, locked;
i = *buflen;
error = 0;
pfs_lock(pd);
if (vp->v_type == VDIR && pd->pn_type == pfstype_root) {
*dvp = vp;
vhold(*dvp);
pfs_unlock(pd);
PFS_RETURN (0);
} else if (vp->v_type == VDIR && pd->pn_type == pfstype_procdir) {
len = snprintf(pidbuf, sizeof(pidbuf), "%d", pid);
i -= len;
if (i < 0) {
error = ENOMEM;
goto failed;
}
bcopy(pidbuf, buf + i, len);
} else {
len = strlen(pd->pn_name);
i -= len;
if (i < 0) {
error = ENOMEM;
goto failed;
}
bcopy(pd->pn_name, buf + i, len);
}
pn = pd->pn_parent;
pfs_unlock(pd);
mp = vp->v_mount;
error = vfs_busy(mp, 0);
if (error)
return (error);
/*
* vp is held by caller.
*/
locked = VOP_ISLOCKED(vp);
VOP_UNLOCK(vp, 0);
error = pfs_vncache_alloc(mp, dvp, pn, pid);
if (error) {
vn_lock(vp, locked | LK_RETRY);
vfs_unbusy(mp);
PFS_RETURN(error);
}
*buflen = i;
VOP_UNLOCK(*dvp, 0);
vn_lock(vp, locked | LK_RETRY);
vfs_unbusy(mp);
PFS_RETURN (0);
failed:
pfs_unlock(pd);
PFS_RETURN(error);
}
/*
* Look up a file or directory
*/
static int
pfs_lookup(struct vop_cachedlookup_args *va)
{
struct vnode *vn = va->a_dvp;
struct vnode **vpp = va->a_vpp;
struct componentname *cnp = va->a_cnp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pd = pvd->pvd_pn;
struct pfs_node *pn, *pdn = NULL;
struct mount *mp;
pid_t pid = pvd->pvd_pid;
char *pname;
int error, i, namelen, visible;
PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr));
pfs_assert_not_owned(pd);
if (vn->v_type != VDIR)
PFS_RETURN (ENOTDIR);
KASSERT_PN_IS_DIR(pd);
error = VOP_ACCESS(vn, VEXEC, cnp->cn_cred, cnp->cn_thread);
if (error)
PFS_RETURN (error);
/*
* Don't support DELETE or RENAME. CREATE is supported so
* that O_CREAT will work, but the lookup will still fail if
* the file does not exist.
*/
if ((cnp->cn_flags & ISLASTCN) &&
(cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
PFS_RETURN (EOPNOTSUPP);
/* shortcut: check if the name is too long */
if (cnp->cn_namelen >= PFS_NAMELEN)
PFS_RETURN (ENOENT);
/* check that parent directory is visible... */
if (!pfs_visible(curthread, pd, pvd->pvd_pid, NULL))
PFS_RETURN (ENOENT);
/* self */
namelen = cnp->cn_namelen;
pname = cnp->cn_nameptr;
if (namelen == 1 && pname[0] == '.') {
pn = pd;
*vpp = vn;
VREF(vn);
PFS_RETURN (0);
}
mp = vn->v_mount;
/* parent */
if (cnp->cn_flags & ISDOTDOT) {
if (pd->pn_type == pfstype_root)
PFS_RETURN (EIO);
error = vfs_busy(mp, MBF_NOWAIT);
if (error != 0) {
vfs_ref(mp);
VOP_UNLOCK(vn, 0);
error = vfs_busy(mp, 0);
vn_lock(vn, LK_EXCLUSIVE | LK_RETRY);
vfs_rel(mp);
if (error != 0)
PFS_RETURN(ENOENT);
if (vn->v_iflag & VI_DOOMED) {
vfs_unbusy(mp);
PFS_RETURN(ENOENT);
}
}
VOP_UNLOCK(vn, 0);
KASSERT(pd->pn_parent != NULL,
("%s(): non-root directory has no parent", __func__));
/*
* This one is tricky. Descendents of procdir nodes
* inherit their parent's process affinity, but
* there's no easy reverse mapping. For simplicity,
* we assume that if this node is a procdir, its
* parent isn't (which is correct as long as
* descendents of procdir nodes are never procdir
* nodes themselves)
*/
if (pd->pn_type == pfstype_procdir)
pid = NO_PID;
pfs_lock(pd);
pn = pd->pn_parent;
pfs_unlock(pd);
goto got_pnode;
}
pfs_lock(pd);
/* named node */
for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next)
if (pn->pn_type == pfstype_procdir)
pdn = pn;
else if (pn->pn_name[namelen] == '\0' &&
bcmp(pname, pn->pn_name, namelen) == 0) {
pfs_unlock(pd);
goto got_pnode;
}
/* process dependent node */
if ((pn = pdn) != NULL) {
pid = 0;
for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i)
if ((pid = pid * 10 + pname[i] - '0') > PID_MAX)
break;
if (i == cnp->cn_namelen) {
pfs_unlock(pd);
goto got_pnode;
}
}
pfs_unlock(pd);
PFS_RETURN (ENOENT);
got_pnode:
pfs_assert_not_owned(pd);
pfs_assert_not_owned(pn);
visible = pfs_visible(curthread, pn, pid, NULL);
if (!visible) {
error = ENOENT;
goto failed;
}
error = pfs_vncache_alloc(mp, vpp, pn, pid);
if (error)
goto failed;
if (cnp->cn_flags & ISDOTDOT) {
vfs_unbusy(mp);
vn_lock(vn, LK_EXCLUSIVE | LK_RETRY);
if (vn->v_iflag & VI_DOOMED) {
vput(*vpp);
*vpp = NULL;
PFS_RETURN(ENOENT);
}
}
if (cnp->cn_flags & MAKEENTRY && !(vn->v_iflag & VI_DOOMED))
cache_enter(vn, *vpp, cnp);
PFS_RETURN (0);
failed:
if (cnp->cn_flags & ISDOTDOT) {
vfs_unbusy(mp);
vn_lock(vn, LK_EXCLUSIVE | LK_RETRY);
*vpp = NULL;
}
PFS_RETURN(error);
}
/*
* Open a file or directory.
*/
static int
pfs_open(struct vop_open_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
int mode = va->a_mode;
PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode));
pfs_assert_not_owned(pn);
/* check if the requested mode is permitted */
if (((mode & FREAD) && !(mode & PFS_RD)) ||
((mode & FWRITE) && !(mode & PFS_WR)))
PFS_RETURN (EPERM);
/* we don't support locking */
if ((mode & O_SHLOCK) || (mode & O_EXLOCK))
PFS_RETURN (EOPNOTSUPP);
PFS_RETURN (0);
}
/*
* Read from a file
*/
static int
pfs_read(struct vop_read_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
struct uio *uio = va->a_uio;
struct proc *proc;
struct sbuf *sb = NULL;
int error, locked;
off_t buflen;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
if (vn->v_type != VREG)
PFS_RETURN (EINVAL);
KASSERT_PN_IS_FILE(pn);
if (!(pn->pn_flags & PFS_RD))
PFS_RETURN (EBADF);
if (pn->pn_fill == NULL)
PFS_RETURN (EIO);
/*
* This is necessary because either process' privileges may
* have changed since the open() call.
*/
if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
PFS_RETURN (EIO);
if (proc != NULL) {
_PHOLD(proc);
PROC_UNLOCK(proc);
}
vhold(vn);
locked = VOP_ISLOCKED(vn);
VOP_UNLOCK(vn, 0);
if (pn->pn_flags & PFS_RAWRD) {
PFS_TRACE(("%zd resid", uio->uio_resid));
error = pn_fill(curthread, proc, pn, NULL, uio);
PFS_TRACE(("%zd resid", uio->uio_resid));
goto ret;
}
if (uio->uio_resid < 0 || uio->uio_offset < 0 ||
uio->uio_resid > OFF_MAX - uio->uio_offset) {
error = EINVAL;
goto ret;
}
buflen = uio->uio_offset + uio->uio_resid;
if (buflen > MAXPHYS)
buflen = MAXPHYS;
sb = sbuf_new(sb, NULL, buflen + 1, 0);
if (sb == NULL) {
error = EIO;
goto ret;
}
error = pn_fill(curthread, proc, pn, sb, uio);
if (error) {
sbuf_delete(sb);
goto ret;
}
/*
* XXX: If the buffer overflowed, sbuf_len() will not return
* the data length. Then just use the full length because an
* overflowed sbuf must be full.
*/
if (sbuf_finish(sb) == 0)
buflen = sbuf_len(sb);
error = uiomove_frombuf(sbuf_data(sb), buflen, uio);
sbuf_delete(sb);
ret:
vn_lock(vn, locked | LK_RETRY);
vdrop(vn);
if (proc != NULL)
PRELE(proc);
PFS_RETURN (error);
}
/*
* Iterate through directory entries
*/
static int
pfs_iterate(struct thread *td, struct proc *proc, struct pfs_node *pd,
struct pfs_node **pn, struct proc **p)
{
int visible;
sx_assert(&allproc_lock, SX_SLOCKED);
pfs_assert_owned(pd);
again:
if (*pn == NULL) {
/* first node */
*pn = pd->pn_nodes;
} else if ((*pn)->pn_type != pfstype_procdir) {
/* next node */
*pn = (*pn)->pn_next;
}
if (*pn != NULL && (*pn)->pn_type == pfstype_procdir) {
/* next process */
if (*p == NULL)
*p = LIST_FIRST(&allproc);
else
*p = LIST_NEXT(*p, p_list);
/* out of processes: next node */
if (*p == NULL)
*pn = (*pn)->pn_next;
else
PROC_LOCK(*p);
}
if ((*pn) == NULL)
return (-1);
if (*p != NULL) {
visible = pfs_visible_proc(td, *pn, *p);
PROC_UNLOCK(*p);
} else if (proc != NULL) {
visible = pfs_visible_proc(td, *pn, proc);
} else {
visible = 1;
}
if (!visible)
goto again;
return (0);
}
/* Directory entry list */
struct pfsentry {
STAILQ_ENTRY(pfsentry) link;
struct dirent entry;
};
STAILQ_HEAD(pfsdirentlist, pfsentry);
/*
* Return directory entries.
*/
static int
pfs_readdir(struct vop_readdir_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pd = pvd->pvd_pn;
pid_t pid = pvd->pvd_pid;
struct proc *p, *proc;
struct pfs_node *pn;
struct uio *uio;
struct pfsentry *pfsent, *pfsent2;
struct pfsdirentlist lst;
off_t offset;
int error, i, resid;
STAILQ_INIT(&lst);
error = 0;
KASSERT(pd->pn_info == vn->v_mount->mnt_data,
("%s(): pn_info does not match mountpoint", __func__));
PFS_TRACE(("%s pid %lu", pd->pn_name, (unsigned long)pid));
pfs_assert_not_owned(pd);
if (vn->v_type != VDIR)
PFS_RETURN (ENOTDIR);
KASSERT_PN_IS_DIR(pd);
uio = va->a_uio;
/* only allow reading entire entries */
offset = uio->uio_offset;
resid = uio->uio_resid;
if (offset < 0 || offset % PFS_DELEN != 0 ||
(resid && resid < PFS_DELEN))
PFS_RETURN (EINVAL);
if (resid == 0)
PFS_RETURN (0);
sx_slock(&allproc_lock);
pfs_lock(pd);
/* check if the directory is visible to the caller */
if (!pfs_visible(curthread, pd, pid, &proc)) {
sx_sunlock(&allproc_lock);
pfs_unlock(pd);
PFS_RETURN (ENOENT);
}
KASSERT(pid == NO_PID || proc != NULL,
("%s(): no process for pid %lu", __func__, (unsigned long)pid));
/* skip unwanted entries */
for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) {
if (pfs_iterate(curthread, proc, pd, &pn, &p) == -1) {
/* nothing left... */
if (proc != NULL)
PROC_UNLOCK(proc);
pfs_unlock(pd);
sx_sunlock(&allproc_lock);
PFS_RETURN (0);
}
}
/* fill in entries */
while (pfs_iterate(curthread, proc, pd, &pn, &p) != -1 &&
resid >= PFS_DELEN) {
if ((pfsent = malloc(sizeof(struct pfsentry), M_IOV,
M_NOWAIT | M_ZERO)) == NULL) {
error = ENOMEM;
break;
}
pfsent->entry.d_reclen = PFS_DELEN;
pfsent->entry.d_fileno = pn_fileno(pn, pid);
/* PFS_DELEN was picked to fit PFS_NAMLEN */
for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i)
pfsent->entry.d_name[i] = pn->pn_name[i];
pfsent->entry.d_namlen = i;
/* NOTE: d_off is the offset of the *next* entry. */
pfsent->entry.d_off = offset + PFS_DELEN;
switch (pn->pn_type) {
case pfstype_procdir:
KASSERT(p != NULL,
("reached procdir node with p == NULL"));
pfsent->entry.d_namlen = snprintf(pfsent->entry.d_name,
PFS_NAMELEN, "%d", p->p_pid);
/* fall through */
case pfstype_root:
case pfstype_dir:
case pfstype_this:
case pfstype_parent:
pfsent->entry.d_type = DT_DIR;
break;
case pfstype_file:
pfsent->entry.d_type = DT_REG;
break;
case pfstype_symlink:
pfsent->entry.d_type = DT_LNK;
break;
default:
panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type);
}
PFS_TRACE(("%s", pfsent->entry.d_name));
dirent_terminate(&pfsent->entry);
STAILQ_INSERT_TAIL(&lst, pfsent, link);
offset += PFS_DELEN;
resid -= PFS_DELEN;
}
if (proc != NULL)
PROC_UNLOCK(proc);
pfs_unlock(pd);
sx_sunlock(&allproc_lock);
i = 0;
STAILQ_FOREACH_SAFE(pfsent, &lst, link, pfsent2) {
if (error == 0)
error = uiomove(&pfsent->entry, PFS_DELEN, uio);
free(pfsent, M_IOV);
i++;
}
PFS_TRACE(("%ju bytes", (uintmax_t)(i * PFS_DELEN)));
PFS_RETURN (error);
}
/*
* Read a symbolic link
*/
static int
pfs_readlink(struct vop_readlink_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
struct uio *uio = va->a_uio;
struct proc *proc = NULL;
char buf[PATH_MAX];
struct sbuf sb;
int error, locked;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
if (vn->v_type != VLNK)
PFS_RETURN (EINVAL);
KASSERT_PN_IS_LINK(pn);
if (pn->pn_fill == NULL)
PFS_RETURN (EIO);
if (pvd->pvd_pid != NO_PID) {
if ((proc = pfind(pvd->pvd_pid)) == NULL)
PFS_RETURN (EIO);
if (proc->p_flag & P_WEXIT) {
PROC_UNLOCK(proc);
PFS_RETURN (EIO);
}
_PHOLD(proc);
PROC_UNLOCK(proc);
}
vhold(vn);
locked = VOP_ISLOCKED(vn);
VOP_UNLOCK(vn, 0);
/* sbuf_new() can't fail with a static buffer */
sbuf_new(&sb, buf, sizeof buf, 0);
error = pn_fill(curthread, proc, pn, &sb, NULL);
if (proc != NULL)
PRELE(proc);
vn_lock(vn, locked | LK_RETRY);
vdrop(vn);
if (error) {
sbuf_delete(&sb);
PFS_RETURN (error);
}
if (sbuf_finish(&sb) != 0) {
sbuf_delete(&sb);
PFS_RETURN (ENAMETOOLONG);
}
error = uiomove_frombuf(sbuf_data(&sb), sbuf_len(&sb), uio);
sbuf_delete(&sb);
PFS_RETURN (error);
}
/*
* Reclaim a vnode
*/
static int
pfs_reclaim(struct vop_reclaim_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
return (pfs_vncache_free(va->a_vp));
}
/*
* Set attributes
*/
static int
pfs_setattr(struct vop_setattr_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
/* Silently ignore unchangeable attributes. */
PFS_RETURN (0);
}
/*
* Write to a file
*/
static int
pfs_write(struct vop_write_args *va)
{
struct vnode *vn = va->a_vp;
struct pfs_vdata *pvd = vn->v_data;
struct pfs_node *pn = pvd->pvd_pn;
struct uio *uio = va->a_uio;
struct proc *proc;
struct sbuf sb;
int error;
PFS_TRACE(("%s", pn->pn_name));
pfs_assert_not_owned(pn);
if (vn->v_type != VREG)
PFS_RETURN (EINVAL);
KASSERT_PN_IS_FILE(pn);
if (!(pn->pn_flags & PFS_WR))
PFS_RETURN (EBADF);
if (pn->pn_fill == NULL)
PFS_RETURN (EIO);
/*
* This is necessary because either process' privileges may
* have changed since the open() call.
*/
if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
PFS_RETURN (EIO);
if (proc != NULL) {
_PHOLD(proc);
PROC_UNLOCK(proc);
}
if (pn->pn_flags & PFS_RAWWR) {
error = pn_fill(curthread, proc, pn, NULL, uio);
if (proc != NULL)
PRELE(proc);
PFS_RETURN (error);
}
sbuf_uionew(&sb, uio, &error);
if (error) {
if (proc != NULL)
PRELE(proc);
PFS_RETURN (error);
}
error = pn_fill(curthread, proc, pn, &sb, uio);
sbuf_delete(&sb);
if (proc != NULL)
PRELE(proc);
PFS_RETURN (error);
}
/*
* Vnode operations
*/
struct vop_vector pfs_vnodeops = {
.vop_default = &default_vnodeops,
.vop_access = pfs_access,
.vop_cachedlookup = pfs_lookup,
.vop_close = pfs_close,
.vop_create = VOP_EOPNOTSUPP,
.vop_getattr = pfs_getattr,
.vop_getextattr = pfs_getextattr,
.vop_ioctl = pfs_ioctl,
.vop_link = VOP_EOPNOTSUPP,
.vop_lookup = vfs_cache_lookup,
.vop_mkdir = VOP_EOPNOTSUPP,
.vop_mknod = VOP_EOPNOTSUPP,
.vop_open = pfs_open,
.vop_read = pfs_read,
.vop_readdir = pfs_readdir,
.vop_readlink = pfs_readlink,
.vop_reclaim = pfs_reclaim,
.vop_remove = VOP_EOPNOTSUPP,
.vop_rename = VOP_EOPNOTSUPP,
.vop_rmdir = VOP_EOPNOTSUPP,
.vop_setattr = pfs_setattr,
.vop_symlink = VOP_EOPNOTSUPP,
.vop_vptocnp = pfs_vptocnp,
.vop_write = pfs_write,
/* XXX I've probably forgotten a few that need VOP_EOPNOTSUPP */
};
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