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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/* Portions Copyright 2007 Shivakumar GN */
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/cmn_err.h>
#include <sys/debug.h>
#include <sys/dirent.h>
#include <sys/kmem.h>
#include <sys/mman.h>
#include <sys/mutex.h>
#include <sys/sysmacros.h>
#include <sys/systm.h>
#include <sys/sunddi.h>
#include <sys/uio.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
#include <sys/cred.h>
#include <sys/gfs.h>
/*
* Generic pseudo-filesystem routines.
*
* There are significant similarities between the implementation of certain file
* system entry points across different filesystems. While one could attempt to
* "choke up on the bat" and incorporate common functionality into a VOP
* preamble or postamble, such an approach is limited in the benefit it can
* provide. In this file we instead define a toolkit of routines which can be
* called from a filesystem (with in-kernel pseudo-filesystems being the focus
* of the exercise) in a more component-like fashion.
*
* There are three basic classes of routines:
*
* 1) Lowlevel support routines
*
* These routines are designed to play a support role for existing
* pseudo-filesystems (such as procfs). They simplify common tasks,
* without forcing the filesystem to hand over management to GFS. The
* routines covered are:
*
* gfs_readdir_init()
* gfs_readdir_emit()
* gfs_readdir_emitn()
* gfs_readdir_pred()
* gfs_readdir_fini()
* gfs_lookup_dot()
*
* 2) Complete GFS management
*
* These routines take a more active role in management of the
* pseudo-filesystem. They handle the relationship between vnode private
* data and VFS data, as well as the relationship between vnodes in the
* directory hierarchy.
*
* In order to use these interfaces, the first member of every private
* v_data must be a gfs_file_t or a gfs_dir_t. This hands over all control
* to GFS.
*
* gfs_file_create()
* gfs_dir_create()
* gfs_root_create()
*
* gfs_file_inactive()
* gfs_dir_inactive()
* gfs_dir_lookup()
* gfs_dir_readdir()
*
* gfs_vop_inactive()
* gfs_vop_lookup()
* gfs_vop_readdir()
* gfs_vop_map()
*
* 3) Single File pseudo-filesystems
*
* This routine creates a rooted file to be overlayed ontop of another
* file in the physical filespace.
*
* Note that the parent is NULL (actually the vfs), but there is nothing
* technically keeping such a file from utilizing the "Complete GFS
* management" set of routines.
*
* gfs_root_create_file()
*/
#ifdef sun
/*
* gfs_make_opsvec: take an array of vnode type definitions and create
* their vnodeops_t structures
*
* This routine takes an array of gfs_opsvec_t's. It could
* alternatively take an array of gfs_opsvec_t*'s, which would allow
* vnode types to be completely defined in files external to the caller
* of gfs_make_opsvec(). As it stands, much more sharing takes place --
* both the caller and the vnode type provider need to access gfsv_ops
* and gfsv_template, and the caller also needs to know gfsv_name.
*/
int
gfs_make_opsvec(gfs_opsvec_t *vec)
{
int error, i;
for (i = 0; ; i++) {
if (vec[i].gfsv_name == NULL)
return (0);
error = vn_make_ops(vec[i].gfsv_name, vec[i].gfsv_template,
vec[i].gfsv_ops);
if (error)
break;
}
cmn_err(CE_WARN, "gfs_make_opsvec: bad vnode ops template for '%s'",
vec[i].gfsv_name);
for (i--; i >= 0; i--) {
vn_freevnodeops(*vec[i].gfsv_ops);
*vec[i].gfsv_ops = NULL;
}
return (error);
}
#endif /* sun */
/*
* Low level directory routines
*
* These routines provide some simple abstractions for reading directories.
* They are designed to be used by existing pseudo filesystems (namely procfs)
* that already have a complicated management infrastructure.
*/
/*
* gfs_get_parent_ino: used to obtain a parent inode number and the
* inode number of the given vnode in preparation for calling gfs_readdir_init.
*/
int
gfs_get_parent_ino(vnode_t *dvp, cred_t *cr, caller_context_t *ct,
ino64_t *pino, ino64_t *ino)
{
vnode_t *parent;
gfs_dir_t *dp = dvp->v_data;
int error;
*ino = dp->gfsd_file.gfs_ino;
parent = dp->gfsd_file.gfs_parent;
if (parent == NULL) {
*pino = *ino; /* root of filesystem */
} else if (dvp->v_flag & V_XATTRDIR) {
#ifdef TODO
vattr_t va;
va.va_mask = AT_NODEID;
error = VOP_GETATTR(parent, &va, 0, cr, ct);
if (error)
return (error);
*pino = va.va_nodeid;
#else
panic("%s:%u: not implemented", __func__, __LINE__);
#endif
} else {
*pino = ((gfs_file_t *)(parent->v_data))->gfs_ino;
}
return (0);
}
/*
* gfs_readdir_init: initiate a generic readdir
* st - a pointer to an uninitialized gfs_readdir_state_t structure
* name_max - the directory's maximum file name length
* ureclen - the exported file-space record length (1 for non-legacy FSs)
* uiop - the uiop passed to readdir
* parent - the parent directory's inode
* self - this directory's inode
* flags - flags from VOP_READDIR
*
* Returns 0 or a non-zero errno.
*
* Typical VOP_READDIR usage of gfs_readdir_*:
*
* if ((error = gfs_readdir_init(...)) != 0)
* return (error);
* eof = 0;
* while ((error = gfs_readdir_pred(..., &voffset)) != 0) {
* if (!consumer_entry_at(voffset))
* voffset = consumer_next_entry(voffset);
* if (consumer_eof(voffset)) {
* eof = 1
* break;
* }
* if ((error = gfs_readdir_emit(..., voffset,
* consumer_ino(voffset), consumer_name(voffset))) != 0)
* break;
* }
* return (gfs_readdir_fini(..., error, eofp, eof));
*
* As you can see, a zero result from gfs_readdir_pred() or
* gfs_readdir_emit() indicates that processing should continue,
* whereas a non-zero result indicates that the loop should terminate.
* Most consumers need do nothing more than let gfs_readdir_fini()
* determine what the cause of failure was and return the appropriate
* value.
*/
int
gfs_readdir_init(gfs_readdir_state_t *st, int name_max, int ureclen,
uio_t *uiop, ino64_t parent, ino64_t self, int flags)
{
size_t dirent_size;
if (uiop->uio_loffset < 0 || uiop->uio_resid <= 0 ||
(uiop->uio_loffset % ureclen) != 0)
return (EINVAL);
st->grd_ureclen = ureclen;
st->grd_oresid = uiop->uio_resid;
st->grd_namlen = name_max;
if (flags & V_RDDIR_ENTFLAGS)
dirent_size = EDIRENT_RECLEN(st->grd_namlen);
else
dirent_size = DIRENT64_RECLEN(st->grd_namlen);
st->grd_dirent = kmem_zalloc(dirent_size, KM_SLEEP);
st->grd_parent = parent;
st->grd_self = self;
st->grd_flags = flags;
return (0);
}
/*
* gfs_readdir_emit_int: internal routine to emit directory entry
*
* st - the current readdir state, which must have d_ino/ed_ino
* and d_name/ed_name set
* uiop - caller-supplied uio pointer
* next - the offset of the next entry
*/
static int
gfs_readdir_emit_int(gfs_readdir_state_t *st, uio_t *uiop, offset_t next,
int *ncookies, u_long **cookies)
{
int reclen, namlen;
dirent64_t *dp;
edirent_t *edp;
if (st->grd_flags & V_RDDIR_ENTFLAGS) {
edp = st->grd_dirent;
namlen = strlen(edp->ed_name);
reclen = EDIRENT_RECLEN(namlen);
} else {
dp = st->grd_dirent;
namlen = strlen(dp->d_name);
reclen = DIRENT64_RECLEN(namlen);
}
if (reclen > uiop->uio_resid) {
/*
* Error if no entries were returned yet
*/
if (uiop->uio_resid == st->grd_oresid)
return (EINVAL);
return (-1);
}
if (st->grd_flags & V_RDDIR_ENTFLAGS) {
edp->ed_off = next;
edp->ed_reclen = (ushort_t)reclen;
} else {
/* XXX: This can change in the future. */
dp->d_reclen = (ushort_t)reclen;
dp->d_type = DT_DIR;
dp->d_namlen = namlen;
}
if (uiomove((caddr_t)st->grd_dirent, reclen, UIO_READ, uiop))
return (EFAULT);
uiop->uio_loffset = next;
if (*cookies != NULL) {
**cookies = next;
(*cookies)++;
(*ncookies)--;
KASSERT(*ncookies >= 0, ("ncookies=%d", *ncookies));
}
return (0);
}
/*
* gfs_readdir_emit: emit a directory entry
* voff - the virtual offset (obtained from gfs_readdir_pred)
* ino - the entry's inode
* name - the entry's name
* eflags - value for ed_eflags (if processing edirent_t)
*
* Returns a 0 on success, a non-zero errno on failure, or -1 if the
* readdir loop should terminate. A non-zero result (either errno or
* -1) from this function is typically passed directly to
* gfs_readdir_fini().
*/
int
gfs_readdir_emit(gfs_readdir_state_t *st, uio_t *uiop, offset_t voff,
ino64_t ino, const char *name, int eflags, int *ncookies, u_long **cookies)
{
offset_t off = (voff + 2) * st->grd_ureclen;
if (st->grd_flags & V_RDDIR_ENTFLAGS) {
edirent_t *edp = st->grd_dirent;
edp->ed_ino = ino;
(void) strncpy(edp->ed_name, name, st->grd_namlen);
edp->ed_eflags = eflags;
} else {
dirent64_t *dp = st->grd_dirent;
dp->d_ino = ino;
(void) strncpy(dp->d_name, name, st->grd_namlen);
}
/*
* Inter-entry offsets are invalid, so we assume a record size of
* grd_ureclen and explicitly set the offset appropriately.
*/
return (gfs_readdir_emit_int(st, uiop, off + st->grd_ureclen, ncookies,
cookies));
}
#ifdef sun
/*
* gfs_readdir_emitn: like gfs_readdir_emit(), but takes an integer
* instead of a string for the entry's name.
*/
int
gfs_readdir_emitn(gfs_readdir_state_t *st, uio_t *uiop, offset_t voff,
ino64_t ino, unsigned long num)
{
char buf[40];
numtos(num, buf);
return (gfs_readdir_emit(st, uiop, voff, ino, buf, 0));
}
#endif
/*
* gfs_readdir_pred: readdir loop predicate
* voffp - a pointer in which the next virtual offset should be stored
*
* Returns a 0 on success, a non-zero errno on failure, or -1 if the
* readdir loop should terminate. A non-zero result (either errno or
* -1) from this function is typically passed directly to
* gfs_readdir_fini().
*/
int
gfs_readdir_pred(gfs_readdir_state_t *st, uio_t *uiop, offset_t *voffp,
int *ncookies, u_long **cookies)
{
offset_t off, voff;
int error;
top:
if (uiop->uio_resid <= 0)
return (-1);
off = uiop->uio_loffset / st->grd_ureclen;
voff = off - 2;
if (off == 0) {
if ((error = gfs_readdir_emit(st, uiop, voff, st->grd_self,
".", 0, ncookies, cookies)) == 0)
goto top;
} else if (off == 1) {
if ((error = gfs_readdir_emit(st, uiop, voff, st->grd_parent,
"..", 0, ncookies, cookies)) == 0)
goto top;
} else {
*voffp = voff;
return (0);
}
return (error);
}
/*
* gfs_readdir_fini: generic readdir cleanup
* error - if positive, an error to return
* eofp - the eofp passed to readdir
* eof - the eof value
*
* Returns a 0 on success, a non-zero errno on failure. This result
* should be returned from readdir.
*/
int
gfs_readdir_fini(gfs_readdir_state_t *st, int error, int *eofp, int eof)
{
size_t dirent_size;
if (st->grd_flags & V_RDDIR_ENTFLAGS)
dirent_size = EDIRENT_RECLEN(st->grd_namlen);
else
dirent_size = DIRENT64_RECLEN(st->grd_namlen);
kmem_free(st->grd_dirent, dirent_size);
if (error > 0)
return (error);
if (eofp)
*eofp = eof;
return (0);
}
/*
* gfs_lookup_dot
*
* Performs a basic check for "." and ".." directory entries.
*/
int
gfs_lookup_dot(vnode_t **vpp, vnode_t *dvp, vnode_t *pvp, const char *nm)
{
if (*nm == '\0' || strcmp(nm, ".") == 0) {
VN_HOLD(dvp);
*vpp = dvp;
return (0);
} else if (strcmp(nm, "..") == 0) {
if (pvp == NULL) {
ASSERT(dvp->v_flag & VROOT);
VN_HOLD(dvp);
*vpp = dvp;
} else {
VN_HOLD(pvp);
*vpp = pvp;
}
vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY);
return (0);
}
return (-1);
}
/*
* gfs_file_create(): create a new GFS file
*
* size - size of private data structure (v_data)
* pvp - parent vnode (GFS directory)
* ops - vnode operations vector
*
* In order to use this interface, the parent vnode must have been created by
* gfs_dir_create(), and the private data stored in v_data must have a
* 'gfs_file_t' as its first field.
*
* Given these constraints, this routine will automatically:
*
* - Allocate v_data for the vnode
* - Initialize necessary fields in the vnode
* - Hold the parent
*/
vnode_t *
gfs_file_create(size_t size, vnode_t *pvp, vfs_t *vfsp, vnodeops_t *ops)
{
gfs_file_t *fp;
vnode_t *vp;
int error;
/*
* Allocate vnode and internal data structure
*/
fp = kmem_zalloc(size, KM_SLEEP);
error = getnewvnode("zfs", vfsp, ops, &vp);
ASSERT(error == 0);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
vp->v_data = (caddr_t)fp;
/*
* Set up various pointers
*/
fp->gfs_vnode = vp;
fp->gfs_parent = pvp;
fp->gfs_size = size;
fp->gfs_type = GFS_FILE;
vp->v_vflag |= VV_FORCEINSMQ;
error = insmntque(vp, vfsp);
vp->v_vflag &= ~VV_FORCEINSMQ;
KASSERT(error == 0, ("insmntque() failed: error %d", error));
/*
* Initialize vnode and hold parent.
*/
if (pvp)
VN_HOLD(pvp);
return (vp);
}
/*
* gfs_dir_create: creates a new directory in the parent
*
* size - size of private data structure (v_data)
* pvp - parent vnode (GFS directory)
* ops - vnode operations vector
* entries - NULL-terminated list of static entries (if any)
* maxlen - maximum length of a directory entry
* readdir_cb - readdir callback (see gfs_dir_readdir)
* inode_cb - inode callback (see gfs_dir_readdir)
* lookup_cb - lookup callback (see gfs_dir_lookup)
*
* In order to use this function, the first member of the private vnode
* structure (v_data) must be a gfs_dir_t. For each directory, there are
* static entries, defined when the structure is initialized, and dynamic
* entries, retrieved through callbacks.
*
* If a directory has static entries, then it must supply a inode callback,
* which will compute the inode number based on the parent and the index.
* For a directory with dynamic entries, the caller must supply a readdir
* callback and a lookup callback. If a static lookup fails, we fall back to
* the supplied lookup callback, if any.
*
* This function also performs the same initialization as gfs_file_create().
*/
vnode_t *
gfs_dir_create(size_t struct_size, vnode_t *pvp, vfs_t *vfsp, vnodeops_t *ops,
gfs_dirent_t *entries, gfs_inode_cb inode_cb, int maxlen,
gfs_readdir_cb readdir_cb, gfs_lookup_cb lookup_cb)
{
vnode_t *vp;
gfs_dir_t *dp;
gfs_dirent_t *de;
vp = gfs_file_create(struct_size, pvp, vfsp, ops);
vp->v_type = VDIR;
dp = vp->v_data;
dp->gfsd_file.gfs_type = GFS_DIR;
dp->gfsd_maxlen = maxlen;
if (entries != NULL) {
for (de = entries; de->gfse_name != NULL; de++)
dp->gfsd_nstatic++;
dp->gfsd_static = kmem_alloc(
dp->gfsd_nstatic * sizeof (gfs_dirent_t), KM_SLEEP);
bcopy(entries, dp->gfsd_static,
dp->gfsd_nstatic * sizeof (gfs_dirent_t));
}
dp->gfsd_readdir = readdir_cb;
dp->gfsd_lookup = lookup_cb;
dp->gfsd_inode = inode_cb;
mutex_init(&dp->gfsd_lock, NULL, MUTEX_DEFAULT, NULL);
return (vp);
}
/*
* gfs_root_create(): create a root vnode for a GFS filesystem
*
* Similar to gfs_dir_create(), this creates a root vnode for a filesystem. The
* only difference is that it takes a vfs_t instead of a vnode_t as its parent.
*/
vnode_t *
gfs_root_create(size_t size, vfs_t *vfsp, vnodeops_t *ops, ino64_t ino,
gfs_dirent_t *entries, gfs_inode_cb inode_cb, int maxlen,
gfs_readdir_cb readdir_cb, gfs_lookup_cb lookup_cb)
{
vnode_t *vp;
VFS_HOLD(vfsp);
vp = gfs_dir_create(size, NULL, vfsp, ops, entries, inode_cb,
maxlen, readdir_cb, lookup_cb);
/* Manually set the inode */
((gfs_file_t *)vp->v_data)->gfs_ino = ino;
vp->v_flag |= VROOT;
return (vp);
}
#ifdef sun
/*
* gfs_root_create_file(): create a root vnode for a GFS file as a filesystem
*
* Similar to gfs_root_create(), this creates a root vnode for a file to
* be the pseudo-filesystem.
*/
vnode_t *
gfs_root_create_file(size_t size, vfs_t *vfsp, vnodeops_t *ops, ino64_t ino)
{
vnode_t *vp = gfs_file_create(size, NULL, ops);
((gfs_file_t *)vp->v_data)->gfs_ino = ino;
VFS_HOLD(vfsp);
VN_SET_VFS_TYPE_DEV(vp, vfsp, VREG, 0);
vp->v_flag |= VROOT | VNOCACHE | VNOMAP | VNOSWAP | VNOMOUNT;
return (vp);
}
#endif /* sun */
/*
* gfs_file_inactive()
*
* Called from the VOP_INACTIVE() routine. If necessary, this routine will
* remove the given vnode from the parent directory and clean up any references
* in the VFS layer.
*
* If the vnode was not removed (due to a race with vget), then NULL is
* returned. Otherwise, a pointer to the private data is returned.
*/
void *
gfs_file_inactive(vnode_t *vp)
{
int i;
gfs_dirent_t *ge = NULL;
gfs_file_t *fp = vp->v_data;
gfs_dir_t *dp = NULL;
void *data;
if (fp->gfs_parent == NULL || (vp->v_flag & V_XATTRDIR))
goto found;
/*
* XXX cope with a FreeBSD-specific race wherein the parent's
* snapshot data can be freed before the parent is
*/
if ((dp = fp->gfs_parent->v_data) == NULL)
return (NULL);
/*
* First, see if this vnode is cached in the parent.
*/
gfs_dir_lock(dp);
/*
* Find it in the set of static entries.
*/
for (i = 0; i < dp->gfsd_nstatic; i++) {
ge = &dp->gfsd_static[i];
if (ge->gfse_vnode == vp)
goto found;
}
/*
* If 'ge' is NULL, then it is a dynamic entry.
*/
ge = NULL;
found:
if (vp->v_flag & V_XATTRDIR)
VI_LOCK(fp->gfs_parent);
VI_LOCK(vp);
/*
* Really remove this vnode
*/
data = vp->v_data;
if (ge != NULL) {
/*
* If this was a statically cached entry, simply set the
* cached vnode to NULL.
*/
ge->gfse_vnode = NULL;
}
VI_UNLOCK(vp);
/*
* Free vnode and release parent
*/
if (fp->gfs_parent) {
if (dp)
gfs_dir_unlock(dp);
VI_LOCK(fp->gfs_parent);
fp->gfs_parent->v_usecount--;
VI_UNLOCK(fp->gfs_parent);
} else {
ASSERT(vp->v_vfsp != NULL);
VFS_RELE(vp->v_vfsp);
}
if (vp->v_flag & V_XATTRDIR)
VI_UNLOCK(fp->gfs_parent);
return (data);
}
/*
* gfs_dir_inactive()
*
* Same as above, but for directories.
*/
void *
gfs_dir_inactive(vnode_t *vp)
{
gfs_dir_t *dp;
ASSERT(vp->v_type == VDIR);
if ((dp = gfs_file_inactive(vp)) != NULL) {
mutex_destroy(&dp->gfsd_lock);
if (dp->gfsd_nstatic)
kmem_free(dp->gfsd_static,
dp->gfsd_nstatic * sizeof (gfs_dirent_t));
}
return (dp);
}
/*
* gfs_dir_lookup_dynamic()
*
* This routine looks up the provided name amongst the dynamic entries
* in the gfs directory and returns the corresponding vnode, if found.
*
* The gfs directory is expected to be locked by the caller prior to
* calling this function. The directory will be unlocked during the
* execution of this function, but will be locked upon return from the
* function. This function returns 0 on success, non-zero on error.
*
* The dynamic lookups are performed by invoking the lookup
* callback, which is passed to this function as the first argument.
* The arguments to the callback are:
*
* int gfs_lookup_cb(vnode_t *pvp, const char *nm, vnode_t **vpp, cred_t *cr,
* int flags, int *deflgs, pathname_t *rpnp);
*
* pvp - parent vnode
* nm - name of entry
* vpp - pointer to resulting vnode
* cr - pointer to cred
* flags - flags value from lookup request
* ignored here; currently only used to request
* insensitive lookups
* direntflgs - output parameter, directory entry flags
* ignored here; currently only used to indicate a lookup
* has more than one possible match when case is not considered
* realpnp - output parameter, real pathname
* ignored here; when lookup was performed case-insensitively,
* this field contains the "real" name of the file.
*
* Returns 0 on success, non-zero on error.
*/
static int
gfs_dir_lookup_dynamic(gfs_lookup_cb callback, gfs_dir_t *dp,
const char *nm, vnode_t *dvp, vnode_t **vpp, cred_t *cr, int flags,
int *direntflags, pathname_t *realpnp)
{
gfs_file_t *fp;
ino64_t ino;
int ret;
ASSERT(GFS_DIR_LOCKED(dp));
/*
* Drop the directory lock, as the lookup routine
* will need to allocate memory, or otherwise deadlock on this
* directory.
*/
gfs_dir_unlock(dp);
ret = callback(dvp, nm, vpp, &ino, cr, flags, direntflags, realpnp);
gfs_dir_lock(dp);
/*
* The callback for extended attributes returns a vnode
* with v_data from an underlying fs.
*/
if (ret == 0 && !IS_XATTRDIR(dvp)) {
fp = (gfs_file_t *)((*vpp)->v_data);
fp->gfs_index = -1;
fp->gfs_ino = ino;
}
return (ret);
}
/*
* gfs_dir_lookup_static()
*
* This routine looks up the provided name amongst the static entries
* in the gfs directory and returns the corresponding vnode, if found.
* The first argument to the function is a pointer to the comparison
* function this function should use to decide if names are a match.
*
* If a match is found, and GFS_CACHE_VNODE is set and the vnode
* exists, we simply return the existing vnode. Otherwise, we call
* the static entry's callback routine, caching the result if
* necessary. If the idx pointer argument is non-NULL, we use it to
* return the index of the matching static entry.
*
* The gfs directory is expected to be locked by the caller prior to calling
* this function. The directory may be unlocked during the execution of
* this function, but will be locked upon return from the function.
*
* This function returns 0 if a match is found, ENOENT if not.
*/
static int
gfs_dir_lookup_static(int (*compare)(const char *, const char *),
gfs_dir_t *dp, const char *nm, vnode_t *dvp, int *idx,
vnode_t **vpp, pathname_t *rpnp)
{
gfs_dirent_t *ge;
vnode_t *vp = NULL;
int i;
ASSERT(GFS_DIR_LOCKED(dp));
/*
* Search static entries.
*/
for (i = 0; i < dp->gfsd_nstatic; i++) {
ge = &dp->gfsd_static[i];
if (compare(ge->gfse_name, nm) == 0) {
if (rpnp)
(void) strlcpy(rpnp->pn_buf, ge->gfse_name,
rpnp->pn_bufsize);
if (ge->gfse_vnode) {
ASSERT(ge->gfse_flags & GFS_CACHE_VNODE);
vp = ge->gfse_vnode;
VN_HOLD(vp);
break;
}
/*
* We drop the directory lock, as the constructor will
* need to do KM_SLEEP allocations. If we return from
* the constructor only to find that a parallel
* operation has completed, and GFS_CACHE_VNODE is set
* for this entry, we discard the result in favor of
* the cached vnode.
*/
gfs_dir_unlock(dp);
vp = ge->gfse_ctor(dvp);
gfs_dir_lock(dp);
((gfs_file_t *)vp->v_data)->gfs_index = i;
/* Set the inode according to the callback. */
((gfs_file_t *)vp->v_data)->gfs_ino =
dp->gfsd_inode(dvp, i);
if (ge->gfse_flags & GFS_CACHE_VNODE) {
if (ge->gfse_vnode == NULL) {
ge->gfse_vnode = vp;
} else {
/*
* A parallel constructor beat us to it;
* return existing vnode. We have to be
* careful because we can't release the
* current vnode while holding the
* directory lock; its inactive routine
* will try to lock this directory.
*/
vnode_t *oldvp = vp;
vp = ge->gfse_vnode;
VN_HOLD(vp);
gfs_dir_unlock(dp);
VN_RELE(oldvp);
gfs_dir_lock(dp);
}
}
break;
}
}
if (vp == NULL)
return (ENOENT);
else if (idx)
*idx = i;
*vpp = vp;
return (0);
}
/*
* gfs_dir_lookup()
*
* Looks up the given name in the directory and returns the corresponding
* vnode, if found.
*
* First, we search statically defined entries, if any, with a call to
* gfs_dir_lookup_static(). If no static entry is found, and we have
* a callback function we try a dynamic lookup via gfs_dir_lookup_dynamic().
*
* This function returns 0 on success, non-zero on error.
*/
int
gfs_dir_lookup(vnode_t *dvp, const char *nm, vnode_t **vpp, cred_t *cr,
int flags, int *direntflags, pathname_t *realpnp)
{
gfs_dir_t *dp = dvp->v_data;
boolean_t casecheck;
vnode_t *dynvp = NULL;
vnode_t *vp = NULL;
int (*compare)(const char *, const char *);
int error, idx;
ASSERT(dvp->v_type == VDIR);
if (gfs_lookup_dot(vpp, dvp, dp->gfsd_file.gfs_parent, nm) == 0)
return (0);
casecheck = (flags & FIGNORECASE) != 0 && direntflags != NULL;
if (vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) ||
(flags & FIGNORECASE))
compare = strcasecmp;
else
compare = strcmp;
gfs_dir_lock(dp);
error = gfs_dir_lookup_static(compare, dp, nm, dvp, &idx, &vp, realpnp);
if (vp && casecheck) {
gfs_dirent_t *ge;
int i;
for (i = idx + 1; i < dp->gfsd_nstatic; i++) {
ge = &dp->gfsd_static[i];
if (strcasecmp(ge->gfse_name, nm) == 0) {
*direntflags |= ED_CASE_CONFLICT;
goto out;
}
}
}
if ((error || casecheck) && dp->gfsd_lookup)
error = gfs_dir_lookup_dynamic(dp->gfsd_lookup, dp, nm, dvp,
&dynvp, cr, flags, direntflags, vp ? NULL : realpnp);
if (vp && dynvp) {
/* static and dynamic entries are case-insensitive conflict */
ASSERT(casecheck);
*direntflags |= ED_CASE_CONFLICT;
VN_RELE(dynvp);
} else if (vp == NULL) {
vp = dynvp;
} else if (error == ENOENT) {
error = 0;
} else if (error) {
VN_RELE(vp);
vp = NULL;
}
out:
gfs_dir_unlock(dp);
*vpp = vp;
return (error);
}
/*
* gfs_dir_readdir: does a readdir() on the given directory
*
* dvp - directory vnode
* uiop - uio structure
* eofp - eof pointer
* data - arbitrary data passed to readdir callback
*
* This routine does all the readdir() dirty work. Even so, the caller must
* supply two callbacks in order to get full compatibility.
*
* If the directory contains static entries, an inode callback must be
* specified. This avoids having to create every vnode and call VOP_GETATTR()
* when reading the directory. This function has the following arguments:
*
* ino_t gfs_inode_cb(vnode_t *vp, int index);
*
* vp - vnode for the directory
* index - index in original gfs_dirent_t array
*
* Returns the inode number for the given entry.
*
* For directories with dynamic entries, a readdir callback must be provided.
* This is significantly more complex, thanks to the particulars of
* VOP_READDIR().
*
* int gfs_readdir_cb(vnode_t *vp, void *dp, int *eofp,
* offset_t *off, offset_t *nextoff, void *data, int flags)
*
* vp - directory vnode
* dp - directory entry, sized according to maxlen given to
* gfs_dir_create(). callback must fill in d_name and
* d_ino (if a dirent64_t), or ed_name, ed_ino, and ed_eflags
* (if an edirent_t). edirent_t is used if V_RDDIR_ENTFLAGS
* is set in 'flags'.
* eofp - callback must set to 1 when EOF has been reached
* off - on entry, the last offset read from the directory. Callback
* must set to the offset of the current entry, typically left
* untouched.
* nextoff - callback must set to offset of next entry. Typically
* (off + 1)
* data - caller-supplied data
* flags - VOP_READDIR flags
*
* Return 0 on success, or error on failure.
*/
int
gfs_dir_readdir(vnode_t *dvp, uio_t *uiop, int *eofp, int *ncookies,
u_long **cookies, void *data, cred_t *cr, int flags)
{
gfs_readdir_state_t gstate;
int error, eof = 0;
ino64_t ino, pino;
offset_t off, next;
gfs_dir_t *dp = dvp->v_data;
error = gfs_get_parent_ino(dvp, cr, NULL, &pino, &ino);
if (error)
return (error);
if ((error = gfs_readdir_init(&gstate, dp->gfsd_maxlen, 1, uiop,
pino, ino, flags)) != 0)
return (error);
while ((error = gfs_readdir_pred(&gstate, uiop, &off, ncookies,
cookies)) == 0 && !eof) {
if (off >= 0 && off < dp->gfsd_nstatic) {
ino = dp->gfsd_inode(dvp, off);
if ((error = gfs_readdir_emit(&gstate, uiop,
off, ino, dp->gfsd_static[off].gfse_name, 0,
ncookies, cookies)) != 0)
break;
} else if (dp->gfsd_readdir) {
off -= dp->gfsd_nstatic;
if ((error = dp->gfsd_readdir(dvp,
gstate.grd_dirent, &eof, &off, &next,
data, flags)) != 0 || eof)
break;
off += dp->gfsd_nstatic + 2;
next += dp->gfsd_nstatic + 2;
if ((error = gfs_readdir_emit_int(&gstate, uiop,
next, ncookies, cookies)) != 0)
break;
} else {
/*
* Offset is beyond the end of the static entries, and
* we have no dynamic entries. Set EOF.
*/
eof = 1;
}
}
return (gfs_readdir_fini(&gstate, error, eofp, eof));
}
/*
* gfs_vop_lookup: VOP_LOOKUP() entry point
*
* For use directly in vnode ops table. Given a GFS directory, calls
* gfs_dir_lookup() as necessary.
*/
/* ARGSUSED */
int
gfs_vop_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, pathname_t *pnp,
int flags, vnode_t *rdir, cred_t *cr, caller_context_t *ct,
int *direntflags, pathname_t *realpnp)
{
return (gfs_dir_lookup(dvp, nm, vpp, cr, flags, direntflags, realpnp));
}
/*
* gfs_vop_readdir: VOP_READDIR() entry point
*
* For use directly in vnode ops table. Given a GFS directory, calls
* gfs_dir_readdir() as necessary.
*/
/* ARGSUSED */
int
gfs_vop_readdir(ap)
struct vop_readdir_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
int *a_eofflag;
int *ncookies;
u_long **a_cookies;
} */ *ap;
{
vnode_t *vp = ap->a_vp;
uio_t *uiop = ap->a_uio;
cred_t *cr = ap->a_cred;
int *eofp = ap->a_eofflag;
int ncookies = 0;
u_long *cookies = NULL;
int error;
if (ap->a_ncookies) {
/*
* Minimum entry size is dirent size and 1 byte for a file name.
*/
ncookies = uiop->uio_resid / (sizeof(struct dirent) - sizeof(((struct dirent *)NULL)->d_name) + 1);
cookies = malloc(ncookies * sizeof(u_long), M_TEMP, M_WAITOK);
*ap->a_cookies = cookies;
*ap->a_ncookies = ncookies;
}
error = gfs_dir_readdir(vp, uiop, eofp, &ncookies, &cookies, NULL,
cr, 0);
if (error == 0) {
/* Subtract unused cookies */
if (ap->a_ncookies)
*ap->a_ncookies -= ncookies;
} else if (ap->a_ncookies) {
free(*ap->a_cookies, M_TEMP);
*ap->a_cookies = NULL;
*ap->a_ncookies = 0;
}
return (error);
}
#ifdef sun
/*
* gfs_vop_map: VOP_MAP() entry point
*
* Convenient routine for handling pseudo-files that wish to allow mmap() calls.
* This function only works for readonly files, and uses the read function for
* the vnode to fill in the data. The mapped data is immediately faulted in and
* filled with the necessary data during this call; there are no getpage() or
* putpage() routines.
*/
/* ARGSUSED */
int
gfs_vop_map(vnode_t *vp, offset_t off, struct as *as, caddr_t *addrp,
size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cred,
caller_context_t *ct)
{
int rv;
ssize_t resid = len;
/*
* Check for bad parameters
*/
#ifdef _ILP32
if (len > MAXOFF_T)
return (ENOMEM);
#endif
if (vp->v_flag & VNOMAP)
return (ENOTSUP);
if (off > MAXOFF_T)
return (EFBIG);
if ((long)off < 0 || (long)(off + len) < 0)
return (EINVAL);
if (vp->v_type != VREG)
return (ENODEV);
if ((prot & (PROT_EXEC | PROT_WRITE)) != 0)
return (EACCES);
/*
* Find appropriate address if needed, otherwise clear address range.
*/
as_rangelock(as);
rv = choose_addr(as, addrp, len, off, ADDR_VACALIGN, flags);
if (rv != 0) {
as_rangeunlock(as);
return (rv);
}
/*
* Create mapping
*/
rv = as_map(as, *addrp, len, segvn_create, zfod_argsp);
as_rangeunlock(as);
if (rv != 0)
return (rv);
/*
* Fill with data from read()
*/
rv = vn_rdwr(UIO_READ, vp, *addrp, len, off, UIO_USERSPACE,
0, (rlim64_t)0, cred, &resid);
if (rv == 0 && resid != 0)
rv = ENXIO;
if (rv != 0) {
as_rangelock(as);
(void) as_unmap(as, *addrp, len);
as_rangeunlock(as);
}
return (rv);
}
#endif /* sun */
/*
* gfs_vop_inactive: VOP_INACTIVE() entry point
*
* Given a vnode that is a GFS file or directory, call gfs_file_inactive() or
* gfs_dir_inactive() as necessary, and kmem_free()s associated private data.
*/
/* ARGSUSED */
int
gfs_vop_inactive(ap)
struct vop_inactive_args /* {
struct vnode *a_vp;
struct thread *a_td;
} */ *ap;
{
vnode_t *vp = ap->a_vp;
gfs_file_t *fp = vp->v_data;
if (fp->gfs_type == GFS_DIR)
gfs_dir_inactive(vp);
else
gfs_file_inactive(vp);
VI_LOCK(vp);
vp->v_data = NULL;
VI_UNLOCK(vp);
kmem_free(fp, fp->gfs_size);
return (0);
}