/* * linux/fs/9p/vfs_inode.c * * This file contains vfs inode ops for the 9P2000 protocol. * * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to: * Free Software Foundation * 51 Franklin Street, Fifth Floor * Boston, MA 02111-1301 USA * */ #include <linux/module.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/file.h> #include <linux/pagemap.h> #include <linux/stat.h> #include <linux/string.h> #include <linux/smp_lock.h> #include <linux/inet.h> #include <linux/namei.h> #include <linux/idr.h> #include "debug.h" #include "v9fs.h" #include "9p.h" #include "v9fs_vfs.h" #include "fid.h" static struct inode_operations v9fs_dir_inode_operations; static struct inode_operations v9fs_dir_inode_operations_ext; static struct inode_operations v9fs_file_inode_operations; static struct inode_operations v9fs_symlink_inode_operations; /** * unixmode2p9mode - convert unix mode bits to plan 9 * @v9ses: v9fs session information * @mode: mode to convert * */ static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode) { int res; res = mode & 0777; if (S_ISDIR(mode)) res |= V9FS_DMDIR; if (v9ses->extended) { if (S_ISLNK(mode)) res |= V9FS_DMSYMLINK; if (v9ses->nodev == 0) { if (S_ISSOCK(mode)) res |= V9FS_DMSOCKET; if (S_ISFIFO(mode)) res |= V9FS_DMNAMEDPIPE; if (S_ISBLK(mode)) res |= V9FS_DMDEVICE; if (S_ISCHR(mode)) res |= V9FS_DMDEVICE; } if ((mode & S_ISUID) == S_ISUID) res |= V9FS_DMSETUID; if ((mode & S_ISGID) == S_ISGID) res |= V9FS_DMSETGID; if ((mode & V9FS_DMLINK)) res |= V9FS_DMLINK; } return res; } /** * p9mode2unixmode- convert plan9 mode bits to unix mode bits * @v9ses: v9fs session information * @mode: mode to convert * */ static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode) { int res; res = mode & 0777; if ((mode & V9FS_DMDIR) == V9FS_DMDIR) res |= S_IFDIR; else if ((mode & V9FS_DMSYMLINK) && (v9ses->extended)) res |= S_IFLNK; else if ((mode & V9FS_DMSOCKET) && (v9ses->extended) && (v9ses->nodev == 0)) res |= S_IFSOCK; else if ((mode & V9FS_DMNAMEDPIPE) && (v9ses->extended) && (v9ses->nodev == 0)) res |= S_IFIFO; else if ((mode & V9FS_DMDEVICE) && (v9ses->extended) && (v9ses->nodev == 0)) res |= S_IFBLK; else res |= S_IFREG; if (v9ses->extended) { if ((mode & V9FS_DMSETUID) == V9FS_DMSETUID) res |= S_ISUID; if ((mode & V9FS_DMSETGID) == V9FS_DMSETGID) res |= S_ISGID; } return res; } int v9fs_uflags2omode(int uflags) { int ret; ret = 0; switch (uflags&3) { default: case O_RDONLY: ret = V9FS_OREAD; break; case O_WRONLY: ret = V9FS_OWRITE; break; case O_RDWR: ret = V9FS_ORDWR; break; } if (uflags & O_EXCL) ret |= V9FS_OEXCL; if (uflags & O_TRUNC) ret |= V9FS_OTRUNC; if (uflags & O_APPEND) ret |= V9FS_OAPPEND; return ret; } /** * v9fs_blank_wstat - helper function to setup a 9P stat structure * @v9ses: 9P session info (for determining extended mode) * @wstat: structure to initialize * */ static void v9fs_blank_wstat(struct v9fs_wstat *wstat) { wstat->type = ~0; wstat->dev = ~0; wstat->qid.type = ~0; wstat->qid.version = ~0; *((long long *)&wstat->qid.path) = ~0; wstat->mode = ~0; wstat->atime = ~0; wstat->mtime = ~0; wstat->length = ~0; wstat->name = NULL; wstat->uid = NULL; wstat->gid = NULL; wstat->muid = NULL; wstat->n_uid = ~0; wstat->n_gid = ~0; wstat->n_muid = ~0; wstat->extension = NULL; } /** * v9fs_get_inode - helper function to setup an inode * @sb: superblock * @mode: mode to setup inode with * */ struct inode *v9fs_get_inode(struct super_block *sb, int mode) { struct inode *inode; struct v9fs_session_info *v9ses = sb->s_fs_info; dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode); inode = new_inode(sb); if (inode) { inode->i_mode = mode; inode->i_uid = current->fsuid; inode->i_gid = current->fsgid; inode->i_blksize = sb->s_blocksize; inode->i_blocks = 0; inode->i_rdev = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; inode->i_mapping->a_ops = &v9fs_addr_operations; switch (mode & S_IFMT) { case S_IFIFO: case S_IFBLK: case S_IFCHR: case S_IFSOCK: if(!v9ses->extended) { dprintk(DEBUG_ERROR, "special files without extended mode\n"); return ERR_PTR(-EINVAL); } init_special_inode(inode, inode->i_mode, inode->i_rdev); break; case S_IFREG: inode->i_op = &v9fs_file_inode_operations; inode->i_fop = &v9fs_file_operations; break; case S_IFLNK: if(!v9ses->extended) { dprintk(DEBUG_ERROR, "extended modes used w/o 9P2000.u\n"); return ERR_PTR(-EINVAL); } inode->i_op = &v9fs_symlink_inode_operations; break; case S_IFDIR: inode->i_nlink++; if(v9ses->extended) inode->i_op = &v9fs_dir_inode_operations_ext; else inode->i_op = &v9fs_dir_inode_operations; inode->i_fop = &v9fs_dir_operations; break; default: dprintk(DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n", mode, mode & S_IFMT); return ERR_PTR(-EINVAL); } } else { eprintk(KERN_WARNING, "Problem allocating inode\n"); return ERR_PTR(-ENOMEM); } return inode; } static int v9fs_create(struct v9fs_session_info *v9ses, u32 pfid, char *name, u32 perm, u8 mode, u32 *fidp, struct v9fs_qid *qid, u32 *iounit) { u32 fid; int err; struct v9fs_fcall *fcall; fid = v9fs_get_idpool(&v9ses->fidpool); if (fid < 0) { eprintk(KERN_WARNING, "no free fids available\n"); return -ENOSPC; } err = v9fs_t_walk(v9ses, pfid, fid, NULL, &fcall); if (err < 0) { PRINT_FCALL_ERROR("clone error", fcall); goto error; } kfree(fcall); err = v9fs_t_create(v9ses, fid, name, perm, mode, &fcall); if (err < 0) { PRINT_FCALL_ERROR("create fails", fcall); goto error; } if (iounit) *iounit = fcall->params.rcreate.iounit; if (qid) *qid = fcall->params.rcreate.qid; if (fidp) *fidp = fid; kfree(fcall); return 0; error: if (fid >= 0) v9fs_put_idpool(fid, &v9ses->fidpool); kfree(fcall); return err; } static struct v9fs_fid* v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry) { int err; u32 nfid; struct v9fs_fid *ret; struct v9fs_fcall *fcall; nfid = v9fs_get_idpool(&v9ses->fidpool); if (nfid < 0) { eprintk(KERN_WARNING, "no free fids available\n"); return ERR_PTR(-ENOSPC); } err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name, &fcall); if (err < 0) { PRINT_FCALL_ERROR("walk error", fcall); v9fs_put_idpool(nfid, &v9ses->fidpool); goto error; } kfree(fcall); fcall = NULL; ret = v9fs_fid_create(v9ses, nfid); if (!ret) { err = -ENOMEM; goto clunk_fid; } err = v9fs_fid_insert(ret, dentry); if (err < 0) { v9fs_fid_destroy(ret); goto clunk_fid; } return ret; clunk_fid: v9fs_t_clunk(v9ses, nfid); error: kfree(fcall); return ERR_PTR(err); } struct inode * v9fs_inode_from_fid(struct v9fs_session_info *v9ses, u32 fid, struct super_block *sb) { int err, umode; struct inode *ret; struct v9fs_fcall *fcall; ret = NULL; err = v9fs_t_stat(v9ses, fid, &fcall); if (err) { PRINT_FCALL_ERROR("stat error", fcall); goto error; } umode = p9mode2unixmode(v9ses, fcall->params.rstat.stat.mode); ret = v9fs_get_inode(sb, umode); if (IS_ERR(ret)) { err = PTR_ERR(ret); ret = NULL; goto error; } v9fs_stat2inode(&fcall->params.rstat.stat, ret, sb); kfree(fcall); return ret; error: kfree(fcall); if (ret) iput(ret); return ERR_PTR(err); } /** * v9fs_remove - helper function to remove files and directories * @dir: directory inode that is being deleted * @file: dentry that is being deleted * @rmdir: removing a directory * */ static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir) { struct v9fs_fcall *fcall = NULL; struct super_block *sb = NULL; struct v9fs_session_info *v9ses = NULL; struct v9fs_fid *v9fid = NULL; struct inode *file_inode = NULL; int fid = -1; int result = 0; dprintk(DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file, rmdir); file_inode = file->d_inode; sb = file_inode->i_sb; v9ses = v9fs_inode2v9ses(file_inode); v9fid = v9fs_fid_lookup(file); if (!v9fid) { dprintk(DEBUG_ERROR, "no v9fs_fid\n"); return -EBADF; } fid = v9fid->fid; if (fid < 0) { dprintk(DEBUG_ERROR, "inode #%lu, no fid!\n", file_inode->i_ino); return -EBADF; } result = v9fs_t_remove(v9ses, fid, &fcall); if (result < 0) { PRINT_FCALL_ERROR("remove fails", fcall); } else { v9fs_put_idpool(fid, &v9ses->fidpool); v9fs_fid_destroy(v9fid); } kfree(fcall); return result; } static int v9fs_open_created(struct inode *inode, struct file *file) { return 0; } /** * v9fs_vfs_create - VFS hook to create files * @inode: directory inode that is being deleted * @dentry: dentry that is being deleted * @mode: create permissions * @nd: path information * */ static int v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) { int err; u32 fid, perm, iounit; int flags; struct v9fs_session_info *v9ses; struct v9fs_fid *dfid, *vfid, *ffid; struct inode *inode; struct v9fs_qid qid; struct file *filp; inode = NULL; vfid = NULL; v9ses = v9fs_inode2v9ses(dir); dfid = v9fs_fid_lookup(dentry->d_parent); perm = unixmode2p9mode(v9ses, mode); if (nd && nd->flags & LOOKUP_OPEN) flags = nd->intent.open.flags - 1; else flags = O_RDWR; err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name, perm, v9fs_uflags2omode(flags), &fid, &qid, &iounit); if (err) goto error; vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry); if (IS_ERR(vfid)) { err = PTR_ERR(vfid); vfid = NULL; goto error; } inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto error; } dentry->d_op = &v9fs_dentry_operations; d_instantiate(dentry, inode); if (nd && nd->flags & LOOKUP_OPEN) { ffid = v9fs_fid_create(v9ses, fid); if (!ffid) return -ENOMEM; filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created); if (IS_ERR(filp)) { v9fs_fid_destroy(ffid); return PTR_ERR(filp); } ffid->rdir_pos = 0; ffid->rdir_fcall = NULL; ffid->fidopen = 1; ffid->iounit = iounit; ffid->filp = filp; filp->private_data = ffid; } return 0; error: if (vfid) v9fs_fid_destroy(vfid); if (inode) iput(inode); return err; } /** * v9fs_vfs_mkdir - VFS mkdir hook to create a directory * @inode: inode that is being unlinked * @dentry: dentry that is being unlinked * @mode: mode for new directory * */ static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) { int err; u32 fid, perm; struct v9fs_session_info *v9ses; struct v9fs_fid *dfid, *vfid; struct inode *inode; inode = NULL; vfid = NULL; v9ses = v9fs_inode2v9ses(dir); dfid = v9fs_fid_lookup(dentry->d_parent); perm = unixmode2p9mode(v9ses, mode | S_IFDIR); err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name, perm, V9FS_OREAD, &fid, NULL, NULL); if (err) { dprintk(DEBUG_ERROR, "create error %d\n", err); goto error; } err = v9fs_t_clunk(v9ses, fid); if (err) { dprintk(DEBUG_ERROR, "clunk error %d\n", err); goto error; } vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry); if (IS_ERR(vfid)) { err = PTR_ERR(vfid); vfid = NULL; goto error; } inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto error; } dentry->d_op = &v9fs_dentry_operations; d_instantiate(dentry, inode); return 0; error: if (vfid) v9fs_fid_destroy(vfid); return err; } /** * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode * @dir: inode that is being walked from * @dentry: dentry that is being walked to? * @nameidata: path data * */ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nameidata) { struct super_block *sb; struct v9fs_session_info *v9ses; struct v9fs_fid *dirfid; struct v9fs_fid *fid; struct inode *inode; struct v9fs_fcall *fcall = NULL; int dirfidnum = -1; int newfid = -1; int result = 0; dprintk(DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n", dir, dentry->d_name.name, dentry, nameidata); sb = dir->i_sb; v9ses = v9fs_inode2v9ses(dir); dentry->d_op = &v9fs_dentry_operations; dirfid = v9fs_fid_lookup(dentry->d_parent); if (!dirfid) { dprintk(DEBUG_ERROR, "no dirfid\n"); return ERR_PTR(-EINVAL); } dirfidnum = dirfid->fid; if (dirfidnum < 0) { dprintk(DEBUG_ERROR, "no dirfid for inode %p, #%lu\n", dir, dir->i_ino); return ERR_PTR(-EBADF); } newfid = v9fs_get_idpool(&v9ses->fidpool); if (newfid < 0) { eprintk(KERN_WARNING, "newfid fails!\n"); return ERR_PTR(-ENOSPC); } result = v9fs_t_walk(v9ses, dirfidnum, newfid, (char *)dentry->d_name.name, NULL); if (result < 0) { v9fs_put_idpool(newfid, &v9ses->fidpool); if (result == -ENOENT) { d_add(dentry, NULL); dprintk(DEBUG_VFS, "Return negative dentry %p count %d\n", dentry, atomic_read(&dentry->d_count)); return NULL; } dprintk(DEBUG_ERROR, "walk error:%d\n", result); goto FreeFcall; } result = v9fs_t_stat(v9ses, newfid, &fcall); if (result < 0) { dprintk(DEBUG_ERROR, "stat error\n"); goto FreeFcall; } inode = v9fs_get_inode(sb, p9mode2unixmode(v9ses, fcall->params.rstat.stat.mode)); if (IS_ERR(inode) && (PTR_ERR(inode) == -ENOSPC)) { eprintk(KERN_WARNING, "inode alloc failes, returns %ld\n", PTR_ERR(inode)); result = -ENOSPC; goto FreeFcall; } inode->i_ino = v9fs_qid2ino(&fcall->params.rstat.stat.qid); fid = v9fs_fid_create(v9ses, newfid); if (fid == NULL) { dprintk(DEBUG_ERROR, "couldn't insert\n"); result = -ENOMEM; goto FreeFcall; } result = v9fs_fid_insert(fid, dentry); if (result < 0) goto FreeFcall; fid->qid = fcall->params.rstat.stat.qid; v9fs_stat2inode(&fcall->params.rstat.stat, inode, inode->i_sb); d_add(dentry, inode); kfree(fcall); return NULL; FreeFcall: kfree(fcall); return ERR_PTR(result); } /** * v9fs_vfs_unlink - VFS unlink hook to delete an inode * @i: inode that is being unlinked * @d: dentry that is being unlinked * */ static int v9fs_vfs_unlink(struct inode *i, struct dentry *d) { return v9fs_remove(i, d, 0); } /** * v9fs_vfs_rmdir - VFS unlink hook to delete a directory * @i: inode that is being unlinked * @d: dentry that is being unlinked * */ static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d) { return v9fs_remove(i, d, 1); } /** * v9fs_vfs_rename - VFS hook to rename an inode * @old_dir: old dir inode * @old_dentry: old dentry * @new_dir: new dir inode * @new_dentry: new dentry * */ static int v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { struct inode *old_inode = old_dentry->d_inode; struct v9fs_session_info *v9ses = v9fs_inode2v9ses(old_inode); struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry); struct v9fs_fid *olddirfid = v9fs_fid_lookup(old_dentry->d_parent); struct v9fs_fid *newdirfid = v9fs_fid_lookup(new_dentry->d_parent); struct v9fs_wstat wstat; struct v9fs_fcall *fcall = NULL; int fid = -1; int olddirfidnum = -1; int newdirfidnum = -1; int retval = 0; dprintk(DEBUG_VFS, "\n"); if ((!oldfid) || (!olddirfid) || (!newdirfid)) { dprintk(DEBUG_ERROR, "problem with arguments\n"); return -EBADF; } /* 9P can only handle file rename in the same directory */ if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) { dprintk(DEBUG_ERROR, "old dir and new dir are different\n"); retval = -EPERM; goto FreeFcallnBail; } fid = oldfid->fid; olddirfidnum = olddirfid->fid; newdirfidnum = newdirfid->fid; if (fid < 0) { dprintk(DEBUG_ERROR, "no fid for old file #%lu\n", old_inode->i_ino); retval = -EBADF; goto FreeFcallnBail; } v9fs_blank_wstat(&wstat); wstat.muid = v9ses->name; wstat.name = (char *) new_dentry->d_name.name; retval = v9fs_t_wstat(v9ses, fid, &wstat, &fcall); FreeFcallnBail: if (retval < 0) PRINT_FCALL_ERROR("wstat error", fcall); kfree(fcall); return retval; } /** * v9fs_vfs_getattr - retrieve file metadata * @mnt - mount information * @dentry - file to get attributes on * @stat - metadata structure to populate * */ static int v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) { struct v9fs_fcall *fcall = NULL; struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode); struct v9fs_fid *fid = v9fs_fid_lookup(dentry); int err = -EPERM; dprintk(DEBUG_VFS, "dentry: %p\n", dentry); if (!fid) { dprintk(DEBUG_ERROR, "couldn't find fid associated with dentry\n"); return -EBADF; } err = v9fs_t_stat(v9ses, fid->fid, &fcall); if (err < 0) dprintk(DEBUG_ERROR, "stat error\n"); else { v9fs_stat2inode(&fcall->params.rstat.stat, dentry->d_inode, dentry->d_inode->i_sb); generic_fillattr(dentry->d_inode, stat); } kfree(fcall); return err; } /** * v9fs_vfs_setattr - set file metadata * @dentry: file whose metadata to set * @iattr: metadata assignment structure * */ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr) { struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode); struct v9fs_fid *fid = v9fs_fid_lookup(dentry); struct v9fs_fcall *fcall = NULL; struct v9fs_wstat wstat; int res = -EPERM; dprintk(DEBUG_VFS, "\n"); if (!fid) { dprintk(DEBUG_ERROR, "Couldn't find fid associated with dentry\n"); return -EBADF; } v9fs_blank_wstat(&wstat); if (iattr->ia_valid & ATTR_MODE) wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode); if (iattr->ia_valid & ATTR_MTIME) wstat.mtime = iattr->ia_mtime.tv_sec; if (iattr->ia_valid & ATTR_ATIME) wstat.atime = iattr->ia_atime.tv_sec; if (iattr->ia_valid & ATTR_SIZE) wstat.length = iattr->ia_size; if (v9ses->extended) { if (iattr->ia_valid & ATTR_UID) wstat.n_uid = iattr->ia_uid; if (iattr->ia_valid & ATTR_GID) wstat.n_gid = iattr->ia_gid; } res = v9fs_t_wstat(v9ses, fid->fid, &wstat, &fcall); if (res < 0) PRINT_FCALL_ERROR("wstat error", fcall); kfree(fcall); if (res >= 0) res = inode_setattr(dentry->d_inode, iattr); return res; } /** * v9fs_stat2inode - populate an inode structure with mistat info * @stat: Plan 9 metadata (mistat) structure * @inode: inode to populate * @sb: superblock of filesystem * */ void v9fs_stat2inode(struct v9fs_stat *stat, struct inode *inode, struct super_block *sb) { int n; char ext[32]; struct v9fs_session_info *v9ses = sb->s_fs_info; inode->i_nlink = 1; inode->i_atime.tv_sec = stat->atime; inode->i_mtime.tv_sec = stat->mtime; inode->i_ctime.tv_sec = stat->mtime; inode->i_uid = v9ses->uid; inode->i_gid = v9ses->gid; if (v9ses->extended) { inode->i_uid = stat->n_uid; inode->i_gid = stat->n_gid; } inode->i_mode = p9mode2unixmode(v9ses, stat->mode); if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) { char type = 0; int major = -1; int minor = -1; n = stat->extension.len; if (n > sizeof(ext)-1) n = sizeof(ext)-1; memmove(ext, stat->extension.str, n); ext[n] = 0; sscanf(ext, "%c %u %u", &type, &major, &minor); switch (type) { case 'c': inode->i_mode &= ~S_IFBLK; inode->i_mode |= S_IFCHR; break; case 'b': break; default: dprintk(DEBUG_ERROR, "Unknown special type %c (%.*s)\n", type, stat->extension.len, stat->extension.str); }; inode->i_rdev = MKDEV(major, minor); } else inode->i_rdev = 0; inode->i_size = stat->length; inode->i_blksize = sb->s_blocksize; inode->i_blocks = (inode->i_size + inode->i_blksize - 1) >> sb->s_blocksize_bits; } /** * v9fs_qid2ino - convert qid into inode number * @qid: qid to hash * * BUG: potential for inode number collisions? */ ino_t v9fs_qid2ino(struct v9fs_qid *qid) { u64 path = qid->path + 2; ino_t i = 0; if (sizeof(ino_t) == sizeof(path)) memcpy(&i, &path, sizeof(ino_t)); else i = (ino_t) (path ^ (path >> 32)); return i; } /** * v9fs_readlink - read a symlink's location (internal version) * @dentry: dentry for symlink * @buffer: buffer to load symlink location into * @buflen: length of buffer * */ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) { int retval = -EPERM; struct v9fs_fcall *fcall = NULL; struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode); struct v9fs_fid *fid = v9fs_fid_lookup(dentry); if (!fid) { dprintk(DEBUG_ERROR, "could not resolve fid from dentry\n"); retval = -EBADF; goto FreeFcall; } if (!v9ses->extended) { retval = -EBADF; dprintk(DEBUG_ERROR, "not extended\n"); goto FreeFcall; } dprintk(DEBUG_VFS, " %s\n", dentry->d_name.name); retval = v9fs_t_stat(v9ses, fid->fid, &fcall); if (retval < 0) { dprintk(DEBUG_ERROR, "stat error\n"); goto FreeFcall; } if (!fcall) return -EIO; if (!(fcall->params.rstat.stat.mode & V9FS_DMSYMLINK)) { retval = -EINVAL; goto FreeFcall; } /* copy extension buffer into buffer */ if (fcall->params.rstat.stat.extension.len < buflen) buflen = fcall->params.rstat.stat.extension.len; memcpy(buffer, fcall->params.rstat.stat.extension.str, buflen - 1); buffer[buflen-1] = 0; retval = buflen; FreeFcall: kfree(fcall); return retval; } /** * v9fs_vfs_readlink - read a symlink's location * @dentry: dentry for symlink * @buf: buffer to load symlink location into * @buflen: length of buffer * */ static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer, int buflen) { int retval; int ret; char *link = __getname(); if (buflen > PATH_MAX) buflen = PATH_MAX; dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry); retval = v9fs_readlink(dentry, link, buflen); if (retval > 0) { if ((ret = copy_to_user(buffer, link, retval)) != 0) { dprintk(DEBUG_ERROR, "problem copying to user: %d\n", ret); retval = ret; } } __putname(link); return retval; } /** * v9fs_vfs_follow_link - follow a symlink path * @dentry: dentry for symlink * @nd: nameidata * */ static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd) { int len = 0; char *link = __getname(); dprintk(DEBUG_VFS, "%s n", dentry->d_name.name); if (!link) link = ERR_PTR(-ENOMEM); else { len = v9fs_readlink(dentry, link, strlen(link)); if (len < 0) { __putname(link); link = ERR_PTR(len); } else link[len] = 0; } nd_set_link(nd, link); return NULL; } /** * v9fs_vfs_put_link - release a symlink path * @dentry: dentry for symlink * @nd: nameidata * */ static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p) { char *s = nd_get_link(nd); dprintk(DEBUG_VFS, " %s %s\n", dentry->d_name.name, s); if (!IS_ERR(s)) __putname(s); } static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry, int mode, const char *extension) { int err; u32 fid, perm; struct v9fs_session_info *v9ses; struct v9fs_fid *dfid, *vfid; struct inode *inode; struct v9fs_fcall *fcall; struct v9fs_wstat wstat; fcall = NULL; inode = NULL; vfid = NULL; v9ses = v9fs_inode2v9ses(dir); dfid = v9fs_fid_lookup(dentry->d_parent); perm = unixmode2p9mode(v9ses, mode); if (!v9ses->extended) { dprintk(DEBUG_ERROR, "not extended\n"); return -EPERM; } err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name, perm, V9FS_OREAD, &fid, NULL, NULL); if (err) goto error; err = v9fs_t_clunk(v9ses, fid); if (err) goto error; vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry); if (IS_ERR(vfid)) { err = PTR_ERR(vfid); vfid = NULL; goto error; } inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb); if (IS_ERR(inode)) { err = PTR_ERR(inode); inode = NULL; goto error; } /* issue a Twstat */ v9fs_blank_wstat(&wstat); wstat.muid = v9ses->name; wstat.extension = (char *) extension; err = v9fs_t_wstat(v9ses, vfid->fid, &wstat, &fcall); if (err < 0) { PRINT_FCALL_ERROR("wstat error", fcall); goto error; } kfree(fcall); dentry->d_op = &v9fs_dentry_operations; d_instantiate(dentry, inode); return 0; error: kfree(fcall); if (vfid) v9fs_fid_destroy(vfid); if (inode) iput(inode); return err; } /** * v9fs_vfs_symlink - helper function to create symlinks * @dir: directory inode containing symlink * @dentry: dentry for symlink * @symname: symlink data * * See 9P2000.u RFC for more information * */ static int v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) { dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name, symname); return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname); } /** * v9fs_vfs_link - create a hardlink * @old_dentry: dentry for file to link to * @dir: inode destination for new link * @dentry: dentry for link * */ /* XXX - lots of code dup'd from symlink and creates, * figure out a better reuse strategy */ static int v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) { int retval; struct v9fs_fid *oldfid; char *name; dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name, old_dentry->d_name.name); oldfid = v9fs_fid_lookup(old_dentry); if (!oldfid) { dprintk(DEBUG_ERROR, "can't find oldfid\n"); return -EPERM; } name = __getname(); sprintf(name, "hardlink(%d)\n", oldfid->fid); retval = v9fs_vfs_mkspecial(dir, dentry, V9FS_DMLINK, name); __putname(name); return retval; } /** * v9fs_vfs_mknod - create a special file * @dir: inode destination for new link * @dentry: dentry for file * @mode: mode for creation * @dev_t: device associated with special file * */ static int v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev) { int retval; char *name; dprintk(DEBUG_VFS, " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino, dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev)); if (!new_valid_dev(rdev)) return -EINVAL; name = __getname(); /* build extension */ if (S_ISBLK(mode)) sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev)); else if (S_ISCHR(mode)) sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev)); else if (S_ISFIFO(mode)) *name = 0; else { __putname(name); return -EINVAL; } retval = v9fs_vfs_mkspecial(dir, dentry, mode, name); __putname(name); return retval; } static struct inode_operations v9fs_dir_inode_operations_ext = { .create = v9fs_vfs_create, .lookup = v9fs_vfs_lookup, .symlink = v9fs_vfs_symlink, .link = v9fs_vfs_link, .unlink = v9fs_vfs_unlink, .mkdir = v9fs_vfs_mkdir, .rmdir = v9fs_vfs_rmdir, .mknod = v9fs_vfs_mknod, .rename = v9fs_vfs_rename, .readlink = v9fs_vfs_readlink, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, }; static struct inode_operations v9fs_dir_inode_operations = { .create = v9fs_vfs_create, .lookup = v9fs_vfs_lookup, .unlink = v9fs_vfs_unlink, .mkdir = v9fs_vfs_mkdir, .rmdir = v9fs_vfs_rmdir, .mknod = v9fs_vfs_mknod, .rename = v9fs_vfs_rename, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, }; static struct inode_operations v9fs_file_inode_operations = { .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, }; static struct inode_operations v9fs_symlink_inode_operations = { .readlink = v9fs_vfs_readlink, .follow_link = v9fs_vfs_follow_link, .put_link = v9fs_vfs_put_link, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, };