diff options
Diffstat (limited to 'sys/fs/pseudofs/pseudofs_vnops.c')
| -rw-r--r-- | sys/fs/pseudofs/pseudofs_vnops.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/sys/fs/pseudofs/pseudofs_vnops.c b/sys/fs/pseudofs/pseudofs_vnops.c new file mode 100644 index 0000000..5516100 --- /dev/null +++ b/sys/fs/pseudofs/pseudofs_vnops.c @@ -0,0 +1,419 @@ +/*- + * 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. + * + * $FreeBSD$ + */ + +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/systm.h> +#include <sys/ctype.h> +#include <sys/dirent.h> +#include <sys/mount.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> + +/* + * Verify permissions + */ +static int +pfs_access(struct vop_access_args *va) +{ + struct vnode *vn = va->a_vp; + struct vattr vattr; + int error; + + error = VOP_GETATTR(vn, &vattr, va->a_cred, va->a_p); + if (error) + return (error); + error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid, + vattr.va_gid, va->a_mode, va->a_cred, NULL); + return (error); +} + +/* + * Close a file or directory + */ +static int +pfs_close(struct vop_close_args *va) +{ + return (0); +} + +/* + * Get file attributes + */ +static int +pfs_getattr(struct vop_getattr_args *va) +{ + struct vnode *vn = va->a_vp; + struct pfs_node *pn = (struct pfs_node *)vn->v_data; + struct vattr *vap = va->a_vap; + + VATTR_NULL(vap); + vap->va_type = vn->v_type; + vap->va_mode = pn->pn_mode; + vap->va_fileid = pn->pn_fileno; + vap->va_flags = 0; + vap->va_blocksize = PAGE_SIZE; + vap->va_bytes = vap->va_size = 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; + vap->va_uid = pn->pn_uid; + vap->va_gid = pn->pn_gid; + + return (0); +} + +/* + * Look up a file or directory + */ +static int +pfs_lookup(struct vop_lookup_args *va) +{ + struct vnode *dvp = va->a_dvp; + struct vnode **vpp = va->a_vpp; + struct componentname *cnp = va->a_cnp; +#if 0 + struct pfs_info *pi = (struct pfs_info *)dvp->v_mount->mnt_data; +#endif + struct pfs_node *pd = (struct pfs_node *)dvp->v_data, *pn; + struct proc *p; + char *pname; + int error, i; + pid_t pid; + + if (dvp->v_type != VDIR) + return (ENOTDIR); + + /* don't support CREATE, RENAME or DELETE */ + if (cnp->cn_nameiop != LOOKUP) + return (EROFS); + + /* shortcut */ + if (cnp->cn_namelen >= PFS_NAMELEN) + return (ENOENT); + + /* self */ + pname = cnp->cn_nameptr; + if (cnp->cn_namelen == 1 && *pname == '.') { + pn = pd; + *vpp = dvp; + VREF(dvp); + goto got_vnode; + } + + /* parent */ + if (cnp->cn_flags & ISDOTDOT) { + if (pd->pn_type == pfstype_root) + return (EIO); + KASSERT(pd->pn_parent, ("non-root directory has no parent")); + return pfs_vncache_alloc(dvp->v_mount, vpp, pd->pn_parent); + } + + /* process dependent */ + for (i = 0, pid = 0; i < cnp->cn_namelen && isdigit(pname[i]); ++i) + pid = pid * 10 + pname[i] - '0'; + /* XXX assume that 8 digits is the maximum safe length for a pid */ + if (i == cnp->cn_namelen && i < 8) { + /* see if this directory has process-dependent children */ + for (pn = pd->pn_nodes; pn->pn_type; ++pn) + if (pn->pn_type == pfstype_procdep) + break; + if (pn->pn_type) { + /* XXX pfind(0) should DTRT here */ + p = pid ? pfind(pid) : &proc0; + if (p == NULL) + return (ENOENT); + if (p_can(cnp->cn_proc, p, P_CAN_SEE, NULL)) + /* pretend it doesn't exist */ + return (ENOENT); +#if 0 + if (!pn->pn_shadow) + pfs_create_shadow(pn, p); + pn = pn->pn_shadow; + goto got_pnode; +#else + /* not yet implemented */ + return (EIO); +#endif + } + } + + /* something else */ + for (pn = pd->pn_nodes; pn->pn_type; ++pn) { + for (i = 0; i < cnp->cn_namelen && pn->pn_name[i]; ++i) + if (pname[i] != pn->pn_name[i]) + break; + if (i == cnp->cn_namelen) + goto got_pnode; + } + + return (ENOENT); + got_pnode: + if (!pn->pn_parent) + pn->pn_parent = pd; + error = pfs_vncache_alloc(dvp->v_mount, vpp, pn); + if (error) + return error; + got_vnode: + if (cnp->cn_flags & MAKEENTRY) + cache_enter(dvp, *vpp, cnp); + return (0); +} + +/* + * Open a file or directory. + */ +static int +pfs_open(struct vop_open_args *va) +{ + /* XXX */ + return (0); +} + +/* + * Read from a file + */ +static int +pfs_read(struct vop_read_args *va) +{ + struct vnode *vn = va->a_vp; + struct pfs_node *pn = vn->v_data; + struct uio *uio = va->a_uio; + struct sbuf sb; + char *ps; + int error, xlen; + + if (vn->v_type != VREG) + return (EINVAL); + + error = sbuf_new(&sb, NULL, uio->uio_offset + uio->uio_resid, 0); + if (error) + return (EIO); + + error = (pn->pn_func)(pn, curproc, &sb); + + /* XXX we should possibly detect and handle overflows */ + sbuf_finish(&sb); + ps = sbuf_data(&sb) + uio->uio_offset; + xlen = sbuf_len(&sb) - uio->uio_offset; + xlen = imin(xlen, uio->uio_resid); + error = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio)); + sbuf_delete(&sb); + return (error); +} + +/* + * Return directory entries. + */ +static int +pfs_readdir(struct vop_readdir_args *va) +{ + struct vnode *vn = va->a_vp; + struct pfs_info *pi; + struct pfs_node *pd, *pn; + struct dirent entry; + struct uio *uio; +#if 0 + struct proc *p; +#endif + off_t offset; + int error, i, resid; + + if (vn->v_type != VDIR) + return (ENOTDIR); + pi = (struct pfs_info *)vn->v_mount->mnt_data; + pd = (struct pfs_node *)vn->v_data; + pn = pd->pn_nodes; + 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 < PFS_DELEN) + return (EINVAL); + + /* skip unwanted entries */ + for (; pn->pn_type && offset > 0; ++pn, offset -= PFS_DELEN) + /* nothing */ ; + + /* fill in entries */ + entry.d_reclen = PFS_DELEN; + for (; pn->pn_type && resid > 0; ++pn) { + if (!pn->pn_parent) + pn->pn_parent = pd; + if (!pn->pn_fileno) + pfs_fileno_alloc(pi, pn); + entry.d_fileno = pn->pn_fileno; + /* PFS_DELEN was picked to fit PFS_NAMLEN */ + for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i) + entry.d_name[i] = pn->pn_name[i]; + entry.d_name[i] = 0; + entry.d_namlen = i; + switch (pn->pn_type) { + case pfstype_root: + case pfstype_dir: + case pfstype_this: + case pfstype_parent: + entry.d_type = DT_DIR; + break; + case pfstype_file: + entry.d_type = DT_REG; + break; + case pfstype_symlink: + entry.d_type = DT_LNK; + break; + case pfstype_procdep: + /* don't handle process-dependent nodes here */ + continue; + default: + panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type); + } + if ((error = uiomove((caddr_t)&entry, PFS_DELEN, uio))) + return (error); + offset += PFS_DELEN; + resid -= PFS_DELEN; + } +#if 0 + for (pn = pd->pn_nodes; pn->pn_type && resid > 0; ++pn) { + if (pn->pn_type != pfstype_procdep) + continue; + + sx_slock(&allproc_lock); + p = LIST_FIRST(&allproc); + + sx_sunlock(&allproc_lock); + offset += PFS_DELEN; + resid -= PFS_DELEN; + break; + } +#endif + + uio->uio_offset += offset; + return (0); +} + +/* + * Read a symbolic link + */ +static int +pfs_readlink(struct vop_readlink_args *va) +{ + struct vnode *vn = va->a_vp; + struct pfs_node *pn = vn->v_data; + struct uio *uio = va->a_uio; + char buf[MAXPATHLEN], *ps; + struct sbuf sb; + int error, xlen; + + if (vn->v_type != VLNK) + return (EINVAL); + + /* sbuf_new() can't fail with a static buffer */ + sbuf_new(&sb, buf, sizeof buf, 0); + + error = (pn->pn_func)(pn, curproc, &sb); + + /* XXX we should detect and handle overflows */ + sbuf_finish(&sb); + ps = sbuf_data(&sb) + uio->uio_offset; + xlen = sbuf_len(&sb) - uio->uio_offset; + xlen = imin(xlen, uio->uio_resid); + error = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio)); + sbuf_delete(&sb); + return (error); +} + +/* + * Reclaim a vnode + */ +static int +pfs_reclaim(struct vop_reclaim_args *va) +{ + return (pfs_vncache_free(va->a_vp)); +} + +/* + * Set attributes + */ +static int +pfs_setattr(struct vop_setattr_args *va) +{ + if (va->a_vap->va_flags != VNOVAL) + return (EOPNOTSUPP); + return (0); +} + +/* + * Dummy operations + */ +static int pfs_erofs(void *va) { return (EROFS); } +static int pfs_null(void *va) { return (0); } + +/* + * Vnode operations + */ +vop_t **pfs_vnodeop_p; +static struct vnodeopv_entry_desc pfs_vnodeop_entries[] = { + { &vop_default_desc, (vop_t *)vop_defaultop }, + { &vop_access_desc, (vop_t *)pfs_access }, + { &vop_close_desc, (vop_t *)pfs_close }, + { &vop_create_desc, (vop_t *)pfs_erofs }, + { &vop_getattr_desc, (vop_t *)pfs_getattr }, + { &vop_link_desc, (vop_t *)pfs_erofs }, + { &vop_lookup_desc, (vop_t *)pfs_lookup }, + { &vop_mkdir_desc, (vop_t *)pfs_erofs }, + { &vop_open_desc, (vop_t *)pfs_open }, + { &vop_read_desc, (vop_t *)pfs_read }, + { &vop_readdir_desc, (vop_t *)pfs_readdir }, + { &vop_readlink_desc, (vop_t *)pfs_readlink }, + { &vop_reclaim_desc, (vop_t *)pfs_reclaim }, + { &vop_remove_desc, (vop_t *)pfs_erofs }, + { &vop_rename_desc, (vop_t *)pfs_erofs }, + { &vop_rmdir_desc, (vop_t *)pfs_erofs }, + { &vop_setattr_desc, (vop_t *)pfs_setattr }, + { &vop_symlink_desc, (vop_t *)pfs_erofs }, + { &vop_write_desc, (vop_t *)pfs_erofs }, + /* XXX I've probably forgotten a few that need pfs_erofs */ + { NULL, (vop_t *)NULL } +}; + +static struct vnodeopv_desc pfs_vnodeop_opv_desc = + { &pfs_vnodeop_p, pfs_vnodeop_entries }; + +VNODEOP_SET(pfs_vnodeop_opv_desc); + |
