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freebsd-nq/sys/miscfs/devfs/devfs_vnops.c

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Reviewed by: no-one yet, but nonintrusive until configed in.. :) Submitted by: julian@freebsd.org Obtained from: written from scratch
1995-04-20 03:31:34 +00:00
/*
* Written by Julian Elischer (julian@DIALix.oz.au)
*
* $Header: /sys/miscfs/devfs/RCS/devfs_vnops.c,v 1.3 1995/01/07 04:20:25 root Exp root $
*
* symlinks can wait 'til later.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/resourcevar.h> /* defines plimit structure in proc struct */
#include <sys/kernel.h>
#include <sys/file.h> /* define FWRITE ... */
#include <sys/stat.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
/*#include <miscfs/specfs/specdev.h>*/ /* plimit structure in the proc struct */
#include <sys/malloc.h>
#include <sys/dir.h> /* defines dirent structure */
/*#include "vnode_if.h"*/ /* must be included elsewhere (vnode.h?)*/
#include "devfsdefs.h"
/*extern struct timeval time,boottime;*/
/*
* Insert description here
*/
/*
* Convert a component of a pathname into a pointer to a locked devfs_front.
* This is a very central and rather complicated routine.
* If the file system is not maintained in a strict tree hierarchy,
* this can result in a deadlock situation (see comments in code below).
*
* The flag argument is LOOKUP, CREATE, RENAME, or DELETE depending on
* whether the name is to be looked up, created, renamed, or deleted.
* When CREATE, RENAME, or DELETE is specified, information usable in
* creating, renaming, or deleting a directory entry may be calculated.
* If flag has LOCKPARENT or'ed into it and the target of the pathname
* exists, lookup returns both the target and its parent directory locked.
* When creating or renaming and LOCKPARENT is specified, the target may
* not be ".". When deleting and LOCKPARENT is specified, the target may
* be "."., but the caller must check to ensure it does an vrele and DNUNLOCK
* instead of two DNUNLOCKs.
*
* Overall outline of devfs_lookup:
*
* check accessibility of directory
* null terminate the component (lookup leaves the whole string alone)
* look for name in cache, if found, then if at end of path
* and deleting or creating, drop it, else return name
* search for name in directory, to found or notfound
* notfound:
* if creating, return locked directory,
* else return error
* found:
* if at end of path and deleting, return information to allow delete
* if at end of path and rewriting (RENAME and LOCKPARENT), lock target
* devfs_front and return info to allow rewrite
* if not at end, add name to cache; if at end and neither creating
* nor deleting, add name to cache
* On return to lookup, remove the null termination we put in at the start.
*
* NOTE: (LOOKUP | LOCKPARENT) currently returns the parent devfs_front unlocked.
*/
int devfs_lookup(ap)
struct vop_lookup_args /* {
struct vnode * a_dvp; directory vnode ptr
struct vnode ** a_vpp; where to put the result
struct componentname * a_cnp; the name we want
} */ *ap;
{
struct componentname *cnp = ap->a_cnp;
struct vnode *dir_vnode = ap->a_dvp;
struct vnode **result_vnode = ap->a_vpp;
dn_p dir_node; /* the directory we are searching */
dn_p new_node; /* the node we are searching for */
int flags = cnp->cn_flags;
int op = cnp->cn_nameiop; /* LOOKUP, CREATE, RENAME, or DELETE */
int lockparent = flags & LOCKPARENT;
int wantparent = flags & (LOCKPARENT|WANTPARENT);
int error = 0;
struct proc *p = cnp->cn_proc;
char heldchar; /* the char at the end of the name componet */
*result_vnode = NULL; /* safe not sorry */ /*XXX*/
DBPRINT(("lookup\n"));
if(devfs_vntodn(dir_vnode,&dir_node))
{
printf("vnode has changed?\n");
vprint("=",dir_vnode);
return(EINVAL);
}
/*
* Check accessiblity of directory.
*/
if (dir_node->type != DEV_DIR)
{
return (ENOTDIR);
}
if (error = VOP_ACCESS(dir_vnode, VEXEC, cnp->cn_cred, cnp->cn_proc))
{
return (error);
}
/*
* We now have a segment name to search for, and a directory to search.
*
* Before tediously performing a linear scan of the directory,
* check the name cache to see if the directory/name pair
* we are looking for is known already.
*/
#ifdef NOT_AT_THE_MOMENT
if (error = cache_lookup(dir_vnode, result_vnode, cnp)) {
int vpid; /* capability number of vnode */
if (error == ENOENT)
return (error);
DBPRINT(("cached "));
/*
* Claim the next vnode in the path.
* See comment below starting `Step through' for
* an explaination of the locking protocol.
*/
if(devfs_vntodn(*result_vnode,&new_node))
{
printf("vnode has changed!?\n");
vprint("=",*result_vnode);
return(EINVAL);
}
vpid = (*result_vnode)->v_id;
if (dir_node == new_node) { /* is "." */
VREF(*result_vnode); /* not a full vget() */
error = 0;
} else if (flags & ISDOTDOT) {/* do a locking dance */
VOP_UNLOCK(dir_vnode);
error = vget(*result_vnode,1);
if (!error && lockparent && (flags & ISLASTCN))
VOP_LOCK(dir_vnode);
} else {
error = vget(*result_vnode,1);
if (!lockparent || error || !(flags & ISLASTCN))
VOP_UNLOCK(dir_vnode);
}
/*
* Check that the capability number did not change
* while we were waiting for the lock.
*/
if (!error) {
if (vpid == (*result_vnode)->v_id)
return (0); /* SUCCCESS, return! */
vput((*result_vnode)); /* pretend we failed */
if (lockparent
&& (dir_node != new_node)
&& (flags & ISLASTCN))
VOP_UNLOCK(dir_vnode);
}
if( error = VOP_LOCK(dir_vnode))
return error;
*result_vnode = NULL; /* safe not sorry */
DBPRINT(("errr, maybe not cached "));
}
#endif
/***********************************************************************\
* SEARCH FOR NAME *
* while making sure the component is null terminated for the strcmp *
\***********************************************************************/
heldchar = cnp->cn_nameptr[cnp->cn_namelen];
cnp->cn_nameptr[cnp->cn_namelen] = '\0';
new_node = dev_findfront(dir_node,cnp->cn_nameptr);
cnp->cn_nameptr[cnp->cn_namelen] = heldchar;
if(new_node)
{
goto found;
}
/***********************************************************************\
* Failed to find it.. (That may be good) *
\***********************************************************************/
/* notfound: */
/*XXX*/ /* possibly release some resources here */
/*
* If creating, and at end of pathname
* then can consider
* allowing file to be created.
* XXX original code (ufs_lookup) checked for . being deleted
*/
if ((op == CREATE || op == RENAME) && (flags & ISLASTCN)) {
/*
* Access for write is interpreted as allowing
* creation of files in the directory.
*/
if (error = VOP_ACCESS(dir_vnode, VWRITE,
cnp->cn_cred, cnp->cn_proc))
{
DBPRINT(("MKACCESS "));
return (error);
}
dir_node->flags |= IUPD|ICHG;/*XXX*/
/*
* We return with the directory locked, so that
* the parameters we set up above will still be
* valid if we actually decide to do a direnter().
* We return ni_vp == NULL to indicate that the entry
* does not currently exist; we leave a pointer to
* the (locked) directory devfs_front in namei_data->ni_dvp.
* The pathname buffer is saved so that the name
* can be obtained later.
*
* NB - if the directory is unlocked, then this
* information cannot be used.
*/
cnp->cn_flags |= SAVENAME;
if (!lockparent)
VOP_UNLOCK(dir_vnode);
/* DON't make a cache entry... status changing */
return (EJUSTRETURN);
}
/*
* Insert name into cache (as non-existent) if appropriate.
*/
if ((cnp->cn_flags & MAKEENTRY) && op != CREATE)
cache_enter(dir_vnode, *result_vnode, cnp);
DBPRINT(("NOT\n"));
return (ENOENT);
/***********************************************************************\
* Found it.. this is not always a good thing.. *
\***********************************************************************/
found:
/*XXX*/ /* possibly release some resources here */
/*
* If deleting, and at end of pathname, return
* parameters which can be used to remove file.
* If the wantparent flag isn't set, we return only
* the directory (in namei_data->ni_dvp), otherwise we go
* on and lock the devfs_front, being careful with ".".
*/
if (op == DELETE && (flags & ISLASTCN)) {
/*
* Write access to directory required to delete files.
*/
if (error = VOP_ACCESS(dir_vnode, VWRITE,
cnp->cn_cred, cnp->cn_proc))
return (error);
/*
*/
if (dir_node == new_node) {
VREF(dir_vnode);
*result_vnode = dir_vnode;
return (0);
}
/*
* If directory is "sticky", then user must own
* the directory, or the file in it, else she
* may not delete it (unless she's root). This
* implements append-only directories.
*/
devfs_dntovn(new_node,result_vnode);
VOP_LOCK((*result_vnode));
#ifdef NOTYET
if ((dir_node->mode & ISVTX) &&
cnp->cn_cred->cr_uid != 0 &&
cnp->cn_cred->cr_uid != dir_node->uid &&
new_node->uid != cnp->cn_cred->cr_uid) {
VOP_UNLOCK((*result_vnode));
return (EPERM);
}
#endif
if (!lockparent)
VOP_UNLOCK(dir_vnode);
return (0);
}
/*
* If rewriting (RENAME), return the devfs_front and the
* information required to rewrite the present directory
* Must get devfs_front of directory entry to verify it's a
* regular file, or empty directory.
*/
if (op == RENAME && wantparent && (flags & ISLASTCN)) {
if (error = VOP_ACCESS(dir_vnode, VWRITE,
cnp->cn_cred, cnp->cn_proc))
return (error);
/*
* Careful about locking second devfs_front.
* This can only occur if the target is ".".
*/
if (dir_node == new_node)
return (EISDIR);
devfs_dntovn(new_node,result_vnode);
VOP_LOCK(*result_vnode);
cnp->cn_flags |= SAVENAME;
if (!lockparent)
VOP_UNLOCK(dir_vnode);
return (0);
}
/*
* Step through the translation in the name. We do not `DNUNLOCK' the
* directory because we may need it again if a symbolic link
* is relative to the current directory. Instead we save it
* unlocked as "saved_dir_node" XXX. We must get the target
* devfs_front before unlocking
* the directory to insure that the devfs_front will not be removed
* before we get it. We prevent deadlock by always fetching
* devfs_fronts from the root, moving down the directory tree. Thus
* when following backward pointers ".." we must unlock the
* parent directory before getting the requested directory.
* There is a potential race condition here if both the current
* and parent directories are removed before the `DNLOCK' for the
* devfs_front associated with ".." returns. We hope that this occurs
* infrequently since we cannot avoid this race condition without
* implementing a sophisticated deadlock detection algorithm.
* Note also that this simple deadlock detection scheme will not
* work if the file system has any hard links other than ".."
* that point backwards in the directory structure.
*/
if (flags & ISDOTDOT) {
VOP_UNLOCK(dir_vnode); /* race to get the devfs_front */
devfs_dntovn(new_node,result_vnode);
VOP_LOCK(*result_vnode);
if (lockparent && (flags & ISLASTCN))
VOP_LOCK(dir_vnode);
} else if (dir_node == new_node) {
VREF(dir_vnode); /* we want ourself, ie "." */
*result_vnode = dir_vnode;
} else {
devfs_dntovn(new_node,result_vnode);
VOP_LOCK(*result_vnode);
if (!lockparent || (flags & ISLASTCN))
VOP_UNLOCK(dir_vnode);
}
/*
* Insert name into cache if appropriate.
*/
if (cnp->cn_flags & MAKEENTRY)
cache_enter(dir_vnode, *result_vnode, cnp);
DBPRINT(("GOT\n"));
return (0);
}
/*
* Create a regular file.
* We must also free the pathname buffer pointed at
* by ndp->ni_pnbuf, always on error, or only if the
* SAVESTART bit in ni_nameiop is clear on success.
* <still true in 4.4?>
*
* Always error... no such thing in this FS
*/
int devfs_create(ap)
struct vop_mknod_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
DBPRINT(("create\n"));
return EINVAL;
}
int devfs_mknod(ap)
struct vop_mknod_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
int error;
DBPRINT(("mknod\n"));
switch (ap->a_vap->va_type) {
case VDIR:
#ifdef VNSLEAZE
return devfs_mkdir(ap);
/*XXX check for WILLRELE settings (different)*/
#else
error = VOP_MKDIR(ap->a_dvp, ap->a_vpp, ap->a_cnp, ap->a_vap);
#endif
break;
/*
* devfs_create() sets ndp->ni_vp.
*/
case VREG:
#ifdef VNSLEAZE
return devfs_create(ap);
/*XXX check for WILLRELE settings (different)*/
#else
error = VOP_CREATE(ap->a_dvp, ap->a_vpp, ap->a_cnp, ap->a_vap);
#endif
break;
default:
return EINVAL;
break;
}
return error;
}
int devfs_open(ap)
struct vop_open_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
DBPRINT(("open\n"));
return 0;
}
int devfs_close(ap)
struct vop_close_args /* {
struct vnode *a_vp;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
DBPRINT(("close\n"));
return 0;
}
int devfs_access(ap)
struct vop_access_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
/*
* mode is filled with a combination of VREAD, VWRITE,
* and/or VEXEC bits turned on. In an octal number these
* are the Y in 0Y00.
*/
struct vnode *vp = ap->a_vp;
int mode = ap->a_mode;
struct ucred *cred = ap->a_cred;
struct proc *p = ap->a_p;
dn_p file_node;
int error;
gid_t *gp;
int i;
DBPRINT(("access\n"));
if (error = devfs_vntodn(vp,&file_node))
{
printf("devfs_vntodn returned %d ",error);
return error;
}
/*
* Root gets to do anything.
*/
if (cred->cr_uid == 0)
return 0;
/*
* Access check is based on only one of owner, group, public.
* If not owner, then check group. If not a member of the
* group, then check public access.
*/
if (cred->cr_uid != file_node->uid)
{
/* failing that.. try groups */
mode >>= 3;
gp = cred->cr_groups;
for (i = 0; i < cred->cr_ngroups; i++, gp++)
{
if (file_node->gid == *gp)
{
goto found;
}
}
/* failing that.. try general access */
mode >>= 3;
found:
;
}
if ((file_node->mode & mode) == mode)
return (0);
return (EACCES);
}
int devfs_getattr(ap)
struct vop_getattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct vattr *vap = ap->a_vap;
struct ucred *cred = ap->a_cred;
struct proc *p = ap->a_p;
dn_p file_node;
int error;
DBPRINT(("getattr\n"));
if (error = devfs_vntodn(vp,&file_node))
{
printf("devfs_vntodn returned %d ",error);
return error;
}
vap->va_rdev = 0;/* default value only */
vap->va_mode = file_node->mode;
switch (file_node->type)
{
case DEV_DIR:
vap->va_rdev = (dev_t)file_node->dvm;
vap->va_mode |= (S_IFDIR);
break;
case DEV_CDEV:
vap->va_rdev = file_node->by.Cdev.dev;
vap->va_mode |= (S_IFCHR);
break;
case DEV_BDEV:
vap->va_rdev = file_node->by.Bdev.dev;
vap->va_mode |= (S_IFBLK);
break;
case DEV_SLNK:
break;
}
vap->va_type = vp->v_type;
vap->va_nlink = file_node->links;
vap->va_uid = file_node->uid;
vap->va_gid = file_node->gid;
vap->va_fsid = (long)file_node->dvm;
vap->va_fileid = (long)file_node;
vap->va_size = file_node->len; /* now a u_quad_t */
vap->va_blocksize = 512;
vap->va_atime = file_node->atime;
vap->va_mtime = file_node->mtime;
vap->va_ctime = file_node->ctime;
vap->va_gen = 0;
vap->va_flags = 0;
vap->va_bytes = file_node->len; /* u_quad_t */
vap->va_filerev = 0; /* XXX */ /* u_quad_t */
vap->va_vaflags = 0; /* XXX */
return 0;
}
int devfs_setattr(ap)
struct vop_setattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct vattr *vap = ap->a_vap;
struct ucred *cred = ap->a_cred;
struct proc *p = ap->a_p;
int error = 0;
dn_p file_node;
if (error = devfs_vntodn(vp,&file_node))
{
printf("devfs_vntodn returned %d ",error);
return error;
}
DBPRINT(("setattr\n"));
if ((vap->va_type != VNON) ||
(vap->va_nlink != VNOVAL) ||
(vap->va_fsid != VNOVAL) ||
(vap->va_fileid != VNOVAL) ||
(vap->va_blocksize != VNOVAL) ||
(vap->va_rdev != VNOVAL) ||
(vap->va_bytes != VNOVAL) ||
(vap->va_gen != VNOVAL) ||
(vap->va_atime.ts_sec != VNOVAL))
{
return EINVAL;
}
if (vap->va_size != VNOVAL) {
return error; /*XXX (?) */
}
if (vap->va_atime.ts_sec != VNOVAL)
{
file_node->atime = vap->va_atime;
}
if (vap->va_mtime.ts_sec != VNOVAL)
{
file_node->mtime = vap->va_mtime;
}
if (vap->va_ctime.ts_sec != VNOVAL)
{
file_node->ctime = vap->va_ctime;
}
if (vap->va_mode != (u_short)VNOVAL)
{
/* set drwxwxrwx stuff */
file_node->mode &= ~07777;
file_node->mode |= vap->va_mode & 07777;
}
if (vap->va_uid != (uid_t)VNOVAL)
{
file_node->uid = vap->va_uid;
}
if (vap->va_gid != (gid_t)VNOVAL)
{
file_node->gid = vap->va_gid;
}
if (vap->va_flags != VNOVAL) {
if (error = suser(cred, &p->p_acflag))
return error;
if (cred->cr_uid == 0)
;
else {
}
}
return error;
}
int devfs_read(ap)
struct vop_read_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
int eof;
int error = 0;
dn_p file_node;
DBPRINT(("read\n"));
if (error = devfs_vntodn(ap->a_vp,&file_node))
{
printf("devfs_vntodn returned %d ",error);
return error;
}
switch (ap->a_vp->v_type) {
case VREG:
return(EINVAL);
case VDIR:
return VOP_READDIR(ap->a_vp,ap->a_uio,ap->a_cred);
case VCHR:
case VBLK:
error = spec_read(ap);
TIMEVAL_TO_TIMESPEC(&time,&(file_node->atime))
return(error);
default:
panic("devfs_read(): bad file type");
break;
}
}
/*
* Write data to a file or directory.
*/
int devfs_write(ap)
struct vop_write_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
dn_p file_node;
int error;
if (error = devfs_vntodn(ap->a_vp,&file_node))
{
printf("devfs_vntodn returned %d ",error);
return error;
}
DBPRINT(("write\n"));
switch (ap->a_vp->v_type) {
case VREG:
return(EINVAL);
case VDIR:
return(EISDIR);
case VCHR:
case VBLK:
error = spec_write(ap);
TIMEVAL_TO_TIMESPEC(&time,&(file_node->mtime))
return(error);
default:
panic("devfs_write(): bad file type");
break;
}
}
int devfs_ioctl(ap)
struct vop_ioctl_args /* {
struct vnode *a_vp;
int a_command;
caddr_t a_data;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
DBPRINT(("ioctl\n"));
return ENOTTY;
}
int devfs_select(ap)
struct vop_select_args /* {
struct vnode *a_vp;
int a_which;
int a_fflags;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
DBPRINT(("select\n"));
return 1; /* DOS filesystems never block? */
}
int devfs_mmap(ap)
struct vop_mmap_args /* {
struct vnode *a_vp;
int a_fflags;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
DBPRINT(("mmap\n"));
return EINVAL;
}
/*
* Flush the blocks of a file to disk.
*/
int devfs_fsync(ap)
struct vop_fsync_args /* {
struct vnode *a_vp;
struct ucred *a_cred;
int a_waitfor;
struct proc *a_p;
} */ *ap;
{
DBPRINT(("fsync\n"));
return(0);
}
int devfs_seek(ap)
struct vop_seek_args /* {
struct vnode *a_vp;
off_t a_oldoff;
off_t a_newoff;
struct ucred *a_cred;
} */ *ap;
{
int error = 0;
DBPRINT(("seek\n"));
return 0;
}
int devfs_remove(ap)
struct vop_remove_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
int error = 0;
/*vrele(DETOV(dep));*/
DBPRINT(("remove\n"));
return error;
}
/*
*/
int devfs_link(ap)
struct vop_link_args /* {
struct vnode *a_vp;
struct vnode *a_tdvp;
struct componentname *a_cnp;
} */ *ap;
{
DBPRINT(("link\n"));
return 0;
}
int devfs_rename(ap)
struct vop_rename_args /* {
struct vnode *a_fdvp;
struct vnode *a_fvp;
struct componentname *a_fcnp;
struct vnode *a_tdvp;
struct vnode *a_tvp;
struct componentname *a_tcnp;
} */ *ap;
{
DBPRINT(("rename\n"));
return 0;
}
int devfs_mkdir(ap)
struct vop_mkdir_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
DBPRINT(("mkdir\n"));
return EINVAL;
}
int devfs_rmdir(ap)
struct vop_rmdir_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
DBPRINT(("rmdir\n"));
return 0;
}
int devfs_symlink(ap)
struct vop_symlink_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
char *a_target;
} */ *ap;
{
return EINVAL;
DBPRINT(("symlink\n"));
}
/*
* Vnode op for readdir
*/
int devfs_readdir(ap)
struct vop_readdir_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct uio *uio = ap->a_uio;
struct ucred *cred = ap->a_cred;
struct dirent dirent;
dn_p dir_node;
Submitted by: julian I did a cleanup on the code.. (why didn't I do that before I checked it in? I hear you ask..)
1995-04-20 07:34:55 +00:00
devnm_p name_node;
Reviewed by: no-one yet, but nonintrusive until configed in.. :) Submitted by: julian@freebsd.org Obtained from: written from scratch
1995-04-20 03:31:34 +00:00
char *name;
int error = 0;
int reclen;
int nodenumber;
int startpos,pos;
DBPRINT(("readdir\n"));
/* set up refs to dir */
if (error = devfs_vntodn(vp,&dir_node))
return error;
if(dir_node->type != DEV_DIR)
return(ENOTDIR);
pos = 0;
startpos = uio->uio_offset;
name_node = dir_node->by.Dir.dirlist;
nodenumber = 0;
TIMEVAL_TO_TIMESPEC(&time,&(dir_node->atime))
while ((name_node || (nodenumber < 2)) && (uio->uio_resid > 0))
{
switch(nodenumber)
{
case 0:
dirent.d_fileno = (unsigned long int)dir_node;
name = ".";
dirent.d_namlen = 1;
break;
case 1:
if(dir_node->by.Dir.parent)
dirent.d_fileno
= (unsigned long int)dir_node->by.Dir.parent;
else
dirent.d_fileno = (unsigned long int)dir_node;
name = "..";
dirent.d_namlen = 2;
break;
default:
dirent.d_fileno =
(unsigned long int)name_node->dnp;
dirent.d_namlen = strlen(name_node->name);
name = name_node->name;
}
reclen = dirent.d_reclen = DIRSIZ (&dirent);
if(pos >= startpos) /* made it to the offset yet? */
{
if (uio->uio_resid < reclen) /* will it fit? */
break;
strcpy( dirent.d_name,name);
if (error = uiomove ((caddr_t)&dirent,
dirent.d_reclen, uio))
break;
}
pos += reclen;
if((nodenumber >1) && name_node)
name_node = name_node->next;
nodenumber++;
}
uio->uio_offset = pos;
return (error);
}
/*
*/
int devfs_readlink(ap)
struct vop_readlink_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
} */ *ap;
{
DBPRINT(("readlink\n"));
return 0;
}
int devfs_abortop(ap)
struct vop_abortop_args /* {
struct vnode *a_dvp;
struct componentname *a_cnp;
} */ *ap;
{
DBPRINT(("abortop\n"));
return 0;
}
int devfs_inactive(ap)
struct vop_inactive_args /* {
struct vnode *a_vp;
} */ *ap;
{
DBPRINT(("inactive\n"));
return 0;
}
int devfs_lock(ap)
struct vop_lock_args *ap;
{
DBPRINT(("lock\n"));
return 0;
}
int devfs_unlock(ap)
struct vop_unlock_args *ap;
{
DBPRINT(("unlock\n"));
return 0;
}
int devfs_islocked(ap)
struct vop_islocked_args /* {
struct vnode *a_vp;
} */ *ap;
{
DBPRINT(("islocked\n"));
return 0;
}
int devfs_bmap(ap)
struct vop_bmap_args /* {
struct vnode *a_vp;
daddr_t a_bn;
struct vnode **a_vpp;
daddr_t *a_bnp;
int *a_runp;
} */ *ap;
{
DBPRINT(("bmap\n"));
return 0;
}
int devfs_strategy(ap)
struct vop_strategy_args /* {
struct buf *a_bp;
} */ *ap;
{
struct vnode *vp;
int error;
DBPRINT(("strategy\n"));
if (ap->a_bp->b_vp->v_type == VBLK || ap->a_bp->b_vp->v_type == VCHR)
printf("devfs_strategy: spec");
return 0;
}
int devfs_advlock(ap)
struct vop_advlock_args /* {
struct vnode *a_vp;
caddr_t a_id;
int a_op;
struct flock *a_fl;
int a_flags;
} */ *ap;
{
DBPRINT(("advlock\n"));
return EINVAL; /* we don't do locking yet */
}
int devfs_reclaim(ap)
struct vop_reclaim_args /* {
struct vnode *a_vp;
} */ *ap;
{
dn_p file_node;
int error;
DBPRINT(("reclaim\n"));
if (error = devfs_vntodn(ap->a_vp,&file_node))
{
printf("devfs_vntodn returned %d ",error);
return error;
}
file_node->vn = 0;
file_node->vn_id = 0;
return(0);
}
/*
* Return POSIX pathconf information applicable to special devices.
*/
int
devfs_pathconf(ap)
struct vop_pathconf_args /* {
struct vnode *a_vp;
int a_name;
int *a_retval;
} */ *ap;
{
switch (ap->a_name) {
case _PC_LINK_MAX:
*ap->a_retval = LINK_MAX;
return (0);
case _PC_MAX_CANON:
*ap->a_retval = MAX_CANON;
return (0);
case _PC_MAX_INPUT:
*ap->a_retval = MAX_INPUT;
return (0);
case _PC_PIPE_BUF:
*ap->a_retval = PIPE_BUF;
return (0);
case _PC_CHOWN_RESTRICTED:
*ap->a_retval = 1;
return (0);
case _PC_VDISABLE:
*ap->a_retval = _POSIX_VDISABLE;
return (0);
default:
return (EINVAL);
}
/* NOTREACHED */
}
/*
* Print out the contents of a /devfs vnode.
*/
/* ARGSUSED */
int
devfs_print(ap)
struct vop_print_args /* {
struct vnode *a_vp;
} */ *ap;
{
printf("tag VT_DEVFS, devfs vnode\n");
return (0);
}
/*void*/
int
devfs_vfree(ap)
struct vop_vfree_args /* {
struct vnode *a_pvp;
ino_t a_ino;
int a_mode;
} */ *ap;
{
return (0);
}
/**************************************************************************\
* pseudo ops *
\**************************************************************************/
/*
* /devfs vnode unsupported operation
*/
int
devfs_enotsupp()
{
return (EOPNOTSUPP);
}
/*
* /devfs "should never get here" operation
*/
int
devfs_badop()
{
panic("devfs: bad op");
/* NOTREACHED */
}
/*
* devfs vnode null operation
*/
int
devfs_nullop()
{
return (0);
}
void devfs_dropvnode(dn_p dnp) /*proto*/
{
struct vnode *vn_p;
if(!dnp)
{
printf("devfs: dn count dropped too early\n");
}
vn_p = dnp->vn;
if(!vn_p)
{
printf("devfs: vn count dropped too early\n");
}
/*
* check if we have a vnode.......
*/
if((vn_p) && ( dnp->vn_id == vn_p->v_id) && (dnp == (dn_p)vn_p->v_data))
{
vgoneall(vn_p);
}
dnp->vn = NULL; /* be pedantic about this */
}
#define devfs_create ((int (*) __P((struct vop_create_args *)))devfs_enotsupp)
#define devfs_mknod ((int (*) __P((struct vop_mknod_args *)))devfs_enotsupp)
#define devfs_close ((int (*) __P((struct vop_close_args *)))nullop)
#define devfs_ioctl ((int (*) __P((struct vop_ioctl_args *)))devfs_enotsupp)
#define devfs_select ((int (*) __P((struct vop_select_args *)))devfs_enotsupp)
#define devfs_mmap ((int (*) __P((struct vop_mmap_args *)))devfs_enotsupp)
#define devfs_fsync ((int (*) __P((struct vop_fsync_args *)))nullop)
#define devfs_seek ((int (*) __P((struct vop_seek_args *)))nullop)
#define devfs_remove ((int (*) __P((struct vop_remove_args *)))devfs_enotsupp)
#define devfs_link ((int (*) __P((struct vop_link_args *)))devfs_enotsupp)
#define devfs_rename ((int (*) __P((struct vop_rename_args *)))devfs_enotsupp)
#define devfs_mkdir ((int (*) __P((struct vop_mkdir_args *)))devfs_enotsupp)
#define devfs_rmdir ((int (*) __P((struct vop_rmdir_args *)))devfs_enotsupp)
#define devfs_symlink ((int (*) __P((struct vop_symlink_args *)))devfs_enotsupp)
#define devfs_readlink \
((int (*) __P((struct vop_readlink_args *)))devfs_enotsupp)
#define devfs_abortop ((int (*) __P((struct vop_abortop_args *)))nullop)
#define devfs_lock ((int (*) __P((struct vop_lock_args *)))nullop)
#define devfs_unlock ((int (*) __P((struct vop_unlock_args *)))nullop)
#define devfs_bmap ((int (*) __P((struct vop_bmap_args *)))devfs_badop)
#define devfs_strategy ((int (*) __P((struct vop_strategy_args *)))devfs_badop)
#define devfs_islocked ((int (*) __P((struct vop_islocked_args *)))nullop)
#define devfs_advlock ((int (*) __P((struct vop_advlock_args *)))devfs_enotsupp)
#define devfs_blkatoff \
((int (*) __P((struct vop_blkatoff_args *)))devfs_enotsupp)
#define devfs_valloc ((int(*) __P(( \
struct vnode *pvp, \
int mode, \
struct ucred *cred, \
struct vnode **vpp))) devfs_enotsupp)
#define devfs_truncate \
((int (*) __P((struct vop_truncate_args *)))devfs_enotsupp)
#define devfs_update ((int (*) __P((struct vop_update_args *)))devfs_enotsupp)
#define devfs_bwrite ((int (*) __P((struct vop_bwrite_args *)))devfs_enotsupp)
/* These are the operations used by directories etc in a devfs */
int (**devfs_vnodeop_p)();
struct vnodeopv_entry_desc devfs_vnodeop_entries[] = {
{ &vop_default_desc, vn_default_error },
{ &vop_lookup_desc, devfs_lookup }, /* lookup */
{ &vop_create_desc, devfs_create }, /* create */
{ &vop_mknod_desc, devfs_mknod }, /* mknod */
{ &vop_open_desc, devfs_open }, /* open */
{ &vop_close_desc, devfs_close }, /* close */
{ &vop_access_desc, devfs_access }, /* access */
{ &vop_getattr_desc, devfs_getattr }, /* getattr */
{ &vop_setattr_desc, devfs_setattr }, /* setattr */
{ &vop_read_desc, devfs_read }, /* read */
{ &vop_write_desc, devfs_write }, /* write */
{ &vop_ioctl_desc, devfs_ioctl }, /* ioctl */
{ &vop_select_desc, devfs_select }, /* select */
{ &vop_mmap_desc, devfs_mmap }, /* mmap */
{ &vop_fsync_desc, devfs_fsync }, /* fsync */
{ &vop_seek_desc, devfs_seek }, /* seek */
{ &vop_remove_desc, devfs_remove }, /* remove */
{ &vop_link_desc, devfs_link }, /* link */
{ &vop_rename_desc, devfs_rename }, /* rename */
{ &vop_mkdir_desc, devfs_mkdir }, /* mkdir */
{ &vop_rmdir_desc, devfs_rmdir }, /* rmdir */
{ &vop_symlink_desc, devfs_symlink }, /* symlink */
{ &vop_readdir_desc, devfs_readdir }, /* readdir */
{ &vop_readlink_desc, devfs_readlink }, /* readlink */
{ &vop_abortop_desc, devfs_abortop }, /* abortop */
{ &vop_inactive_desc, devfs_inactive }, /* inactive */
{ &vop_reclaim_desc, devfs_reclaim }, /* reclaim */
{ &vop_lock_desc, devfs_lock }, /* lock */
{ &vop_unlock_desc, devfs_unlock }, /* unlock */
{ &vop_bmap_desc, devfs_bmap }, /* bmap */
{ &vop_strategy_desc, devfs_strategy }, /* strategy */
{ &vop_print_desc, devfs_print }, /* print */
{ &vop_islocked_desc, devfs_islocked }, /* islocked */
{ &vop_pathconf_desc, devfs_pathconf }, /* pathconf */
{ &vop_advlock_desc, devfs_advlock }, /* advlock */
{ &vop_blkatoff_desc, devfs_blkatoff }, /* blkatoff */
{ &vop_valloc_desc, devfs_valloc }, /* valloc */
{ &vop_vfree_desc, devfs_vfree }, /* vfree */
{ &vop_truncate_desc, devfs_truncate }, /* truncate */
{ &vop_update_desc, devfs_update }, /* update */
{ &vop_bwrite_desc, devfs_bwrite }, /* bwrite */
{ (struct vnodeop_desc*)NULL, (int(*)())NULL }
};
struct vnodeopv_desc devfs_vnodeop_opv_desc =
{ &devfs_vnodeop_p, devfs_vnodeop_entries };
VNODEOP_SET(devfs_vnodeop_opv_desc);
/*copied in from specfs/spec_vnops.c.. (spot the changes )*/
/* These are the operations used by special devices in a devfs */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. 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.
* 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.
*
* @(#)spec_vnops.c 8.6 (Berkeley) 4/9/94
* spec_vnops.c,v 1.9 1994/11/14 13:22:52 bde Exp
*/
#include "../specfs/specdev.h" /* for all the definitions and prototypes */
int (**dev_spec_vnodeop_p)();
struct vnodeopv_entry_desc dev_spec_vnodeop_entries[] = {
{ &vop_default_desc, vn_default_error },
{ &vop_lookup_desc, spec_lookup }, /* lookup */
{ &vop_create_desc, spec_create }, /* create */
{ &vop_mknod_desc, spec_mknod }, /* mknod */
{ &vop_open_desc, spec_open }, /* open */
{ &vop_close_desc, spec_close }, /* close */
{ &vop_access_desc, devfs_access }, /* access */
{ &vop_getattr_desc, devfs_getattr }, /* getattr */
{ &vop_setattr_desc, devfs_setattr }, /* setattr */
{ &vop_read_desc, spec_read }, /* read */
{ &vop_write_desc, spec_write }, /* write */
{ &vop_ioctl_desc, spec_ioctl }, /* ioctl */
{ &vop_select_desc, spec_select }, /* select */
{ &vop_mmap_desc, spec_mmap }, /* mmap */
{ &vop_fsync_desc, spec_fsync }, /* fsync */
{ &vop_seek_desc, spec_seek }, /* seek */
{ &vop_remove_desc, spec_remove }, /* remove */
{ &vop_link_desc, spec_link }, /* link */
{ &vop_rename_desc, spec_rename }, /* rename */
{ &vop_mkdir_desc, spec_mkdir }, /* mkdir */
{ &vop_rmdir_desc, spec_rmdir }, /* rmdir */
{ &vop_symlink_desc, spec_symlink }, /* symlink */
{ &vop_readdir_desc, spec_readdir }, /* readdir */
{ &vop_readlink_desc, spec_readlink }, /* readlink */
{ &vop_abortop_desc, spec_abortop }, /* abortop */
{ &vop_inactive_desc, spec_inactive }, /* inactive */
{ &vop_reclaim_desc, spec_reclaim }, /* reclaim */
{ &vop_lock_desc, spec_lock }, /* lock */
{ &vop_unlock_desc, spec_unlock }, /* unlock */
{ &vop_bmap_desc, spec_bmap }, /* bmap */
{ &vop_strategy_desc, spec_strategy }, /* strategy */
{ &vop_print_desc, spec_print }, /* print */
{ &vop_islocked_desc, spec_islocked }, /* islocked */
{ &vop_pathconf_desc, spec_pathconf }, /* pathconf */
{ &vop_advlock_desc, spec_advlock }, /* advlock */
{ &vop_blkatoff_desc, spec_blkatoff }, /* blkatoff */
{ &vop_valloc_desc, spec_valloc }, /* valloc */
{ &vop_vfree_desc, spec_vfree }, /* vfree */
{ &vop_truncate_desc, spec_truncate }, /* truncate */
{ &vop_update_desc, spec_update }, /* update */
{ &vop_bwrite_desc, spec_bwrite }, /* bwrite */
{ (struct vnodeop_desc*)NULL, (int(*)())NULL }
};
struct vnodeopv_desc dev_spec_vnodeop_opv_desc =
{ &dev_spec_vnodeop_p, dev_spec_vnodeop_entries };
VNODEOP_SET(dev_spec_vnodeop_opv_desc);
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