/* * fs/cifs/dir.c * * vfs operations that deal with dentries * * Copyright (C) International Business Machines Corp., 2002,2009 * Author(s): Steve French (sfrench@us.ibm.com) * * This library is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published * by the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This library 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include "cifsfs.h" #include "cifspdu.h" #include "cifsglob.h" #include "cifsproto.h" #include "cifs_debug.h" #include "cifs_fs_sb.h" static void renew_parental_timestamps(struct dentry *direntry) { /* BB check if there is a way to get the kernel to do this or if we really need this */ do { direntry->d_time = jiffies; direntry = direntry->d_parent; } while (!IS_ROOT(direntry)); } char * cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb, struct cifs_tcon *tcon) { int pplen = vol->prepath ? strlen(vol->prepath) + 1 : 0; int dfsplen; char *full_path = NULL; /* if no prefix path, simply set path to the root of share to "" */ if (pplen == 0) { full_path = kzalloc(1, GFP_KERNEL); return full_path; } if (tcon->Flags & SMB_SHARE_IS_IN_DFS) dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1); else dfsplen = 0; full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL); if (full_path == NULL) return full_path; if (dfsplen) strncpy(full_path, tcon->treeName, dfsplen); full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb); strncpy(full_path + dfsplen + 1, vol->prepath, pplen); convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb)); full_path[dfsplen + pplen] = 0; /* add trailing null */ return full_path; } /* Note: caller must free return buffer */ char * build_path_from_dentry(struct dentry *direntry) { struct dentry *temp; int namelen; int dfsplen; char *full_path; char dirsep; struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb); struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb); unsigned seq; dirsep = CIFS_DIR_SEP(cifs_sb); if (tcon->Flags & SMB_SHARE_IS_IN_DFS) dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1); else dfsplen = 0; cifs_bp_rename_retry: namelen = dfsplen; seq = read_seqbegin(&rename_lock); rcu_read_lock(); for (temp = direntry; !IS_ROOT(temp);) { namelen += (1 + temp->d_name.len); temp = temp->d_parent; if (temp == NULL) { cifs_dbg(VFS, "corrupt dentry\n"); rcu_read_unlock(); return NULL; } } rcu_read_unlock(); full_path = kmalloc(namelen+1, GFP_KERNEL); if (full_path == NULL) return full_path; full_path[namelen] = 0; /* trailing null */ rcu_read_lock(); for (temp = direntry; !IS_ROOT(temp);) { spin_lock(&temp->d_lock); namelen -= 1 + temp->d_name.len; if (namelen < 0) { spin_unlock(&temp->d_lock); break; } else { full_path[namelen] = dirsep; strncpy(full_path + namelen + 1, temp->d_name.name, temp->d_name.len); cifs_dbg(FYI, "name: %s\n", full_path + namelen); } spin_unlock(&temp->d_lock); temp = temp->d_parent; if (temp == NULL) { cifs_dbg(VFS, "corrupt dentry\n"); rcu_read_unlock(); kfree(full_path); return NULL; } } rcu_read_unlock(); if (namelen != dfsplen || read_seqretry(&rename_lock, seq)) { cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n", namelen, dfsplen); /* presumably this is only possible if racing with a rename of one of the parent directories (we can not lock the dentries above us to prevent this, but retrying should be harmless) */ kfree(full_path); goto cifs_bp_rename_retry; } /* DIR_SEP already set for byte 0 / vs \ but not for subsequent slashes in prepath which currently must be entered the right way - not sure if there is an alternative since the '\' is a valid posix character so we can not switch those safely to '/' if any are found in the middle of the prepath */ /* BB test paths to Windows with '/' in the midst of prepath */ if (dfsplen) { strncpy(full_path, tcon->treeName, dfsplen); if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) { int i; for (i = 0; i < dfsplen; i++) { if (full_path[i] == '\\') full_path[i] = '/'; } } } return full_path; } /* * Don't allow the separator character in a path component. * The VFS will not allow "/", but "\" is allowed by posix. */ static int check_name(struct dentry *direntry) { struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb); int i; if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) { for (i = 0; i < direntry->d_name.len; i++) { if (direntry->d_name.name[i] == '\\') { cifs_dbg(FYI, "Invalid file name\n"); return -EINVAL; } } } return 0; } /* Inode operations in similar order to how they appear in Linux file fs.h */ static int cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid, struct tcon_link *tlink, unsigned oflags, umode_t mode, __u32 *oplock, struct cifs_fid *fid, int *created) { int rc = -ENOENT; int create_options = CREATE_NOT_DIR; int desired_access; struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); struct cifs_tcon *tcon = tlink_tcon(tlink); char *full_path = NULL; FILE_ALL_INFO *buf = NULL; struct inode *newinode = NULL; int disposition; struct TCP_Server_Info *server = tcon->ses->server; struct cifs_open_parms oparms; *oplock = 0; if (tcon->ses->server->oplocks) *oplock = REQ_OPLOCK; full_path = build_path_from_dentry(direntry); if (full_path == NULL) { rc = -ENOMEM; goto out; } if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open && (CIFS_UNIX_POSIX_PATH_OPS_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))) { rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode, oflags, oplock, &fid->netfid, xid); switch (rc) { case 0: if (newinode == NULL) { /* query inode info */ goto cifs_create_get_file_info; } if (!S_ISREG(newinode->i_mode)) { /* * The server may allow us to open things like * FIFOs, but the client isn't set up to deal * with that. If it's not a regular file, just * close it and proceed as if it were a normal * lookup. */ CIFSSMBClose(xid, tcon, fid->netfid); goto cifs_create_get_file_info; } /* success, no need to query */ goto cifs_create_set_dentry; case -ENOENT: goto cifs_create_get_file_info; case -EIO: case -EINVAL: /* * EIO could indicate that (posix open) operation is not * supported, despite what server claimed in capability * negotiation. * * POSIX open in samba versions 3.3.1 and earlier could * incorrectly fail with invalid parameter. */ tcon->broken_posix_open = true; break; case -EREMOTE: case -EOPNOTSUPP: /* * EREMOTE indicates DFS junction, which is not handled * in posix open. If either that or op not supported * returned, follow the normal lookup. */ break; default: goto out; } /* * fallthrough to retry, using older open call, this is case * where server does not support this SMB level, and falsely * claims capability (also get here for DFS case which should be * rare for path not covered on files) */ } desired_access = 0; if (OPEN_FMODE(oflags) & FMODE_READ) desired_access |= GENERIC_READ; /* is this too little? */ if (OPEN_FMODE(oflags) & FMODE_WRITE) desired_access |= GENERIC_WRITE; disposition = FILE_OVERWRITE_IF; if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) disposition = FILE_CREATE; else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC)) disposition = FILE_OVERWRITE_IF; else if ((oflags & O_CREAT) == O_CREAT) disposition = FILE_OPEN_IF; else cifs_dbg(FYI, "Create flag not set in create function\n"); /* * BB add processing to set equivalent of mode - e.g. via CreateX with * ACLs */ if (!server->ops->open) { rc = -ENOSYS; goto out; } buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL); if (buf == NULL) { rc = -ENOMEM; goto out; } /* * if we're not using unix extensions, see if we need to set * ATTR_READONLY on the create call */ if (!tcon->unix_ext && (mode & S_IWUGO) == 0) create_options |= CREATE_OPTION_READONLY; if (backup_cred(cifs_sb)) create_options |= CREATE_OPEN_BACKUP_INTENT; oparms.tcon = tcon; oparms.cifs_sb = cifs_sb; oparms.desired_access = desired_access; oparms.create_options = create_options; oparms.disposition = disposition; oparms.path = full_path; oparms.fid = fid; rc = server->ops->open(xid, &oparms, oplock, buf); if (rc) { cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc); goto out; } /* * If Open reported that we actually created a file then we now have to * set the mode if possible. */ if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) { struct cifs_unix_set_info_args args = { .mode = mode, .ctime = NO_CHANGE_64, .atime = NO_CHANGE_64, .mtime = NO_CHANGE_64, .device = 0, }; *created |= FILE_CREATED; if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) { args.uid = current_fsuid(); if (inode->i_mode & S_ISGID) args.gid = inode->i_gid; else args.gid = current_fsgid(); } else { args.uid = INVALID_UID; /* no change */ args.gid = INVALID_GID; /* no change */ } CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid, current->tgid); } else { /* * BB implement mode setting via Windows security * descriptors e.g. */ /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/ /* Could set r/o dos attribute if mode & 0222 == 0 */ } cifs_create_get_file_info: /* server might mask mode so we have to query for it */ if (tcon->unix_ext) rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb, xid); else { rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, &fid->netfid); if (newinode) { if (server->ops->set_lease_key) server->ops->set_lease_key(newinode, fid); if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM) newinode->i_mode = mode; if ((*oplock & CIFS_CREATE_ACTION) && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) { newinode->i_uid = current_fsuid(); if (inode->i_mode & S_ISGID) newinode->i_gid = inode->i_gid; else newinode->i_gid = current_fsgid(); } } } cifs_create_set_dentry: if (rc != 0) { cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n", rc); if (server->ops->close) server->ops->close(xid, tcon, fid); goto out; } d_drop(direntry); d_add(direntry, newinode); out: kfree(buf); kfree(full_path); return rc; } int cifs_atomic_open(struct inode *inode, struct dentry *direntry, struct file *file, unsigned oflags, umode_t mode, int *opened) { int rc; unsigned int xid; struct tcon_link *tlink; struct cifs_tcon *tcon; struct TCP_Server_Info *server; struct cifs_fid fid; struct cifs_pending_open open; __u32 oplock; struct cifsFileInfo *file_info; /* * Posix open is only called (at lookup time) for file create now. For * opens (rather than creates), because we do not know if it is a file * or directory yet, and current Samba no longer allows us to do posix * open on dirs, we could end up wasting an open call on what turns out * to be a dir. For file opens, we wait to call posix open till * cifs_open. It could be added to atomic_open in the future but the * performance tradeoff of the extra network request when EISDIR or * EACCES is returned would have to be weighed against the 50% reduction * in network traffic in the other paths. */ if (!(oflags & O_CREAT)) { struct dentry *res; /* * Check for hashed negative dentry. We have already revalidated * the dentry and it is fine. No need to perform another lookup. */ if (!d_unhashed(direntry)) return -ENOENT; res = cifs_lookup(inode, direntry, 0); if (IS_ERR(res)) return PTR_ERR(res); return finish_no_open(file, res); } rc = check_name(direntry); if (rc) return rc; xid = get_xid(); cifs_dbg(FYI, "parent inode = 0x%p name is: %s and dentry = 0x%p\n", inode, direntry->d_name.name, direntry); tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb)); if (IS_ERR(tlink)) { rc = PTR_ERR(tlink); goto out_free_xid; } tcon = tlink_tcon(tlink); server = tcon->ses->server; if (server->ops->new_lease_key) server->ops->new_lease_key(&fid); cifs_add_pending_open(&fid, tlink, &open); rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, opened); if (rc) { cifs_del_pending_open(&open); goto out; } rc = finish_open(file, direntry, generic_file_open, opened); if (rc) { if (server->ops->close) server->ops->close(xid, tcon, &fid); cifs_del_pending_open(&open); goto out; } file_info = cifs_new_fileinfo(&fid, file, tlink, oplock); if (file_info == NULL) { if (server->ops->close) server->ops->close(xid, tcon, &fid); cifs_del_pending_open(&open); rc = -ENOMEM; } out: cifs_put_tlink(tlink); out_free_xid: free_xid(xid); return rc; } int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode, bool excl) { int rc; unsigned int xid = get_xid(); /* * BB below access is probably too much for mknod to request * but we have to do query and setpathinfo so requesting * less could fail (unless we want to request getatr and setatr * permissions (only). At least for POSIX we do not have to * request so much. */ unsigned oflags = O_EXCL | O_CREAT | O_RDWR; struct tcon_link *tlink; struct cifs_tcon *tcon; struct TCP_Server_Info *server; struct cifs_fid fid; __u32 oplock; int created = FILE_CREATED; cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %s and dentry = 0x%p\n", inode, direntry->d_name.name, direntry); tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb)); rc = PTR_ERR(tlink); if (IS_ERR(tlink)) goto out_free_xid; tcon = tlink_tcon(tlink); server = tcon->ses->server; if (server->ops->new_lease_key) server->ops->new_lease_key(&fid); rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &created); if (!rc && server->ops->close) server->ops->close(xid, tcon, &fid); cifs_put_tlink(tlink); out_free_xid: free_xid(xid); return rc; } int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode, dev_t device_number) { int rc = -EPERM; unsigned int xid; int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL; struct cifs_sb_info *cifs_sb; struct tcon_link *tlink; struct cifs_tcon *pTcon; struct cifs_io_parms io_parms; char *full_path = NULL; struct inode *newinode = NULL; int oplock = 0; u16 fileHandle; FILE_ALL_INFO *buf = NULL; unsigned int bytes_written; struct win_dev *pdev; if (!old_valid_dev(device_number)) return -EINVAL; cifs_sb = CIFS_SB(inode->i_sb); tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); pTcon = tlink_tcon(tlink); xid = get_xid(); full_path = build_path_from_dentry(direntry); if (full_path == NULL) { rc = -ENOMEM; goto mknod_out; } if (pTcon->unix_ext) { struct cifs_unix_set_info_args args = { .mode = mode & ~current_umask(), .ctime = NO_CHANGE_64, .atime = NO_CHANGE_64, .mtime = NO_CHANGE_64, .device = device_number, }; if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) { args.uid = current_fsuid(); args.gid = current_fsgid(); } else { args.uid = INVALID_UID; /* no change */ args.gid = INVALID_GID; /* no change */ } rc = CIFSSMBUnixSetPathInfo(xid, pTcon, full_path, &args, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); if (rc) goto mknod_out; rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb, xid); if (rc == 0) d_instantiate(direntry, newinode); goto mknod_out; } if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL)) goto mknod_out; cifs_dbg(FYI, "sfu compat create special file\n"); buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL); if (buf == NULL) { kfree(full_path); rc = -ENOMEM; free_xid(xid); return rc; } if (backup_cred(cifs_sb)) create_options |= CREATE_OPEN_BACKUP_INTENT; rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_CREATE, GENERIC_WRITE, create_options, &fileHandle, &oplock, buf, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); if (rc) goto mknod_out; /* BB Do not bother to decode buf since no local inode yet to put * timestamps in, but we can reuse it safely */ pdev = (struct win_dev *)buf; io_parms.netfid = fileHandle; io_parms.pid = current->tgid; io_parms.tcon = pTcon; io_parms.offset = 0; io_parms.length = sizeof(struct win_dev); if (S_ISCHR(mode)) { memcpy(pdev->type, "IntxCHR", 8); pdev->major = cpu_to_le64(MAJOR(device_number)); pdev->minor = cpu_to_le64(MINOR(device_number)); rc = CIFSSMBWrite(xid, &io_parms, &bytes_written, (char *)pdev, NULL, 0); } else if (S_ISBLK(mode)) { memcpy(pdev->type, "IntxBLK", 8); pdev->major = cpu_to_le64(MAJOR(device_number)); pdev->minor = cpu_to_le64(MINOR(device_number)); rc = CIFSSMBWrite(xid, &io_parms, &bytes_written, (char *)pdev, NULL, 0); } /* else if (S_ISFIFO) */ CIFSSMBClose(xid, pTcon, fileHandle); d_drop(direntry); /* FIXME: add code here to set EAs */ mknod_out: kfree(full_path); kfree(buf); free_xid(xid); cifs_put_tlink(tlink); return rc; } struct dentry * cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, unsigned int flags) { unsigned int xid; int rc = 0; /* to get around spurious gcc warning, set to zero here */ struct cifs_sb_info *cifs_sb; struct tcon_link *tlink; struct cifs_tcon *pTcon; struct inode *newInode = NULL; char *full_path = NULL; xid = get_xid(); cifs_dbg(FYI, "parent inode = 0x%p name is: %s and dentry = 0x%p\n", parent_dir_inode, direntry->d_name.name, direntry); /* check whether path exists */ cifs_sb = CIFS_SB(parent_dir_inode->i_sb); tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) { free_xid(xid); return (struct dentry *)tlink; } pTcon = tlink_tcon(tlink); rc = check_name(direntry); if (rc) goto lookup_out; /* can not grab the rename sem here since it would deadlock in the cases (beginning of sys_rename itself) in which we already have the sb rename sem */ full_path = build_path_from_dentry(direntry); if (full_path == NULL) { rc = -ENOMEM; goto lookup_out; } if (direntry->d_inode != NULL) { cifs_dbg(FYI, "non-NULL inode in lookup\n"); } else { cifs_dbg(FYI, "NULL inode in lookup\n"); } cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, direntry->d_inode); if (pTcon->unix_ext) { rc = cifs_get_inode_info_unix(&newInode, full_path, parent_dir_inode->i_sb, xid); } else { rc = cifs_get_inode_info(&newInode, full_path, NULL, parent_dir_inode->i_sb, xid, NULL); } if ((rc == 0) && (newInode != NULL)) { d_add(direntry, newInode); /* since paths are not looked up by component - the parent directories are presumed to be good here */ renew_parental_timestamps(direntry); } else if (rc == -ENOENT) { rc = 0; direntry->d_time = jiffies; d_add(direntry, NULL); /* if it was once a directory (but how can we tell?) we could do shrink_dcache_parent(direntry); */ } else if (rc != -EACCES) { cifs_dbg(VFS, "Unexpected lookup error %d\n", rc); /* We special case check for Access Denied - since that is a common return code */ } lookup_out: kfree(full_path); cifs_put_tlink(tlink); free_xid(xid); return ERR_PTR(rc); } static int cifs_d_revalidate(struct dentry *direntry, unsigned int flags) { if (flags & LOOKUP_RCU) return -ECHILD; if (direntry->d_inode) { if (cifs_revalidate_dentry(direntry)) return 0; else { /* * If the inode wasn't known to be a dfs entry when * the dentry was instantiated, such as when created * via ->readdir(), it needs to be set now since the * attributes will have been updated by * cifs_revalidate_dentry(). */ if (IS_AUTOMOUNT(direntry->d_inode) && !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) { spin_lock(&direntry->d_lock); direntry->d_flags |= DCACHE_NEED_AUTOMOUNT; spin_unlock(&direntry->d_lock); } return 1; } } /* * This may be nfsd (or something), anyway, we can't see the * intent of this. So, since this can be for creation, drop it. */ if (!flags) return 0; /* * Drop the negative dentry, in order to make sure to use the * case sensitive name which is specified by user if this is * for creation. */ if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET)) return 0; if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled) return 0; return 1; } /* static int cifs_d_delete(struct dentry *direntry) { int rc = 0; cifs_dbg(FYI, "In cifs d_delete, name = %s\n", direntry->d_name.name); return rc; } */ const struct dentry_operations cifs_dentry_ops = { .d_revalidate = cifs_d_revalidate, .d_automount = cifs_dfs_d_automount, /* d_delete: cifs_d_delete, */ /* not needed except for debugging */ }; static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q) { struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls; unsigned long hash; int i; hash = init_name_hash(); for (i = 0; i < q->len; i++) hash = partial_name_hash(nls_tolower(codepage, q->name[i]), hash); q->hash = end_name_hash(hash); return 0; } static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry, unsigned int len, const char *str, const struct qstr *name) { struct nls_table *codepage = CIFS_SB(parent->d_sb)->local_nls; if ((name->len == len) && (nls_strnicmp(codepage, name->name, str, len) == 0)) return 0; return 1; } const struct dentry_operations cifs_ci_dentry_ops = { .d_revalidate = cifs_d_revalidate, .d_hash = cifs_ci_hash, .d_compare = cifs_ci_compare, .d_automount = cifs_dfs_d_automount, };