/* * fs/cifs/dir.c * * vfs operations that deal with dentries * * Copyright (C) International Business Machines Corp., 2002,2008 * 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 <linux/fs.h> #include <linux/stat.h> #include <linux/slab.h> #include <linux/namei.h> #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)); } /* Note: caller must free return buffer */ char * build_path_from_dentry(struct dentry *direntry) { struct dentry *temp; int namelen; int pplen; int dfsplen; char *full_path; char dirsep; struct cifs_sb_info *cifs_sb; if (direntry == NULL) return NULL; /* not much we can do if dentry is freed and we need to reopen the file after it was closed implicitly when the server crashed */ cifs_sb = CIFS_SB(direntry->d_sb); dirsep = CIFS_DIR_SEP(cifs_sb); pplen = cifs_sb->prepathlen; if (cifs_sb->tcon && (cifs_sb->tcon->Flags & SMB_SHARE_IS_IN_DFS)) dfsplen = strnlen(cifs_sb->tcon->treeName, MAX_TREE_SIZE + 1); else dfsplen = 0; cifs_bp_rename_retry: namelen = pplen + dfsplen; for (temp = direntry; !IS_ROOT(temp);) { namelen += (1 + temp->d_name.len); temp = temp->d_parent; if (temp == NULL) { cERROR(1, ("corrupt dentry")); return NULL; } } full_path = kmalloc(namelen+1, GFP_KERNEL); if (full_path == NULL) return full_path; full_path[namelen] = 0; /* trailing null */ for (temp = direntry; !IS_ROOT(temp);) { namelen -= 1 + temp->d_name.len; if (namelen < 0) { break; } else { full_path[namelen] = dirsep; strncpy(full_path + namelen + 1, temp->d_name.name, temp->d_name.len); cFYI(0, ("name: %s", full_path + namelen)); } temp = temp->d_parent; if (temp == NULL) { cERROR(1, ("corrupt dentry")); kfree(full_path); return NULL; } } if (namelen != pplen + dfsplen) { cERROR(1, ("did not end path lookup where expected namelen is %d", namelen)); /* 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, cifs_sb->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] = '/'; } } } strncpy(full_path + dfsplen, CIFS_SB(direntry->d_sb)->prepath, pplen); return full_path; } /* Inode operations in similar order to how they appear in Linux file fs.h */ int cifs_create(struct inode *inode, struct dentry *direntry, int mode, struct nameidata *nd) { int rc = -ENOENT; int xid; int create_options = CREATE_NOT_DIR; int oplock = 0; int desiredAccess = GENERIC_READ | GENERIC_WRITE; __u16 fileHandle; struct cifs_sb_info *cifs_sb; struct cifsTconInfo *pTcon; char *full_path = NULL; FILE_ALL_INFO *buf = NULL; struct inode *newinode = NULL; struct cifsFileInfo *pCifsFile = NULL; struct cifsInodeInfo *pCifsInode; int disposition = FILE_OVERWRITE_IF; bool write_only = false; xid = GetXid(); cifs_sb = CIFS_SB(inode->i_sb); pTcon = cifs_sb->tcon; full_path = build_path_from_dentry(direntry); if (full_path == NULL) { FreeXid(xid); return -ENOMEM; } if (nd && (nd->flags & LOOKUP_OPEN)) { int oflags = nd->intent.open.flags; desiredAccess = 0; if (oflags & FMODE_READ) desiredAccess |= GENERIC_READ; if (oflags & FMODE_WRITE) { desiredAccess |= GENERIC_WRITE; if (!(oflags & FMODE_READ)) write_only = true; } 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 cFYI(1, ("Create flag not set in create function")); } /* BB add processing to set equivalent of mode - e.g. via CreateX with ACLs */ if (oplockEnabled) oplock = REQ_OPLOCK; buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL); if (buf == NULL) { kfree(full_path); FreeXid(xid); return -ENOMEM; } mode &= ~current->fs->umask; /* * if we're not using unix extensions, see if we need to set * ATTR_READONLY on the create call */ if (!pTcon->unix_ext && (mode & S_IWUGO) == 0) create_options |= CREATE_OPTION_READONLY; if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS) rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess, create_options, &fileHandle, &oplock, buf, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); else rc = -EIO; /* no NT SMB support fall into legacy open below */ if (rc == -EIO) { /* old server, retry the open legacy style */ rc = SMBLegacyOpen(xid, pTcon, full_path, disposition, desiredAccess, create_options, &fileHandle, &oplock, buf, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } if (rc) { cFYI(1, ("cifs_create returned 0x%x", rc)); } else { /* If Open reported that we actually created a file then we now have to set the mode if possible */ if ((pTcon->unix_ext) && (oplock & CIFS_CREATE_ACTION)) { if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) { CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)current->fsuid, (__u64)current->fsgid, 0 /* dev */, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } else { CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)-1, (__u64)-1, 0 /* dev */, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } } else { /* BB implement mode setting via Windows security descriptors e.g. */ /* CIFSSMBWinSetPerms(xid,pTcon,path,mode,-1,-1,nls);*/ /* Could set r/o dos attribute if mode & 0222 == 0 */ } /* server might mask mode so we have to query for it */ if (pTcon->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, &fileHandle); if (newinode) { 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; newinode->i_gid = current->fsgid; } } } if (rc != 0) { cFYI(1, ("Create worked but get_inode_info failed rc = %d", rc)); } else { if (pTcon->nocase) direntry->d_op = &cifs_ci_dentry_ops; else direntry->d_op = &cifs_dentry_ops; d_instantiate(direntry, newinode); } if ((nd == NULL /* nfsd case - nfs srv does not set nd */) || (!(nd->flags & LOOKUP_OPEN))) { /* mknod case - do not leave file open */ CIFSSMBClose(xid, pTcon, fileHandle); } else if (newinode) { pCifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); if (pCifsFile == NULL) goto cifs_create_out; pCifsFile->netfid = fileHandle; pCifsFile->pid = current->tgid; pCifsFile->pInode = newinode; pCifsFile->invalidHandle = false; pCifsFile->closePend = false; init_MUTEX(&pCifsFile->fh_sem); mutex_init(&pCifsFile->lock_mutex); INIT_LIST_HEAD(&pCifsFile->llist); atomic_set(&pCifsFile->wrtPending, 0); /* set the following in open now pCifsFile->pfile = file; */ write_lock(&GlobalSMBSeslock); list_add(&pCifsFile->tlist, &pTcon->openFileList); pCifsInode = CIFS_I(newinode); if (pCifsInode) { /* if readable file instance put first in list*/ if (write_only) { list_add_tail(&pCifsFile->flist, &pCifsInode->openFileList); } else { list_add(&pCifsFile->flist, &pCifsInode->openFileList); } if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) { pCifsInode->clientCanCacheAll = true; pCifsInode->clientCanCacheRead = true; cFYI(1, ("Exclusive Oplock inode %p", newinode)); } else if ((oplock & 0xF) == OPLOCK_READ) pCifsInode->clientCanCacheRead = true; } write_unlock(&GlobalSMBSeslock); } } cifs_create_out: kfree(buf); kfree(full_path); FreeXid(xid); return rc; } int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, dev_t device_number) { int rc = -EPERM; int xid; struct cifs_sb_info *cifs_sb; struct cifsTconInfo *pTcon; char *full_path = NULL; struct inode *newinode = NULL; if (!old_valid_dev(device_number)) return -EINVAL; xid = GetXid(); cifs_sb = CIFS_SB(inode->i_sb); pTcon = cifs_sb->tcon; full_path = build_path_from_dentry(direntry); if (full_path == NULL) rc = -ENOMEM; else if (pTcon->unix_ext) { mode &= ~current->fs->umask; if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) { rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)current->fsuid, (__u64)current->fsgid, device_number, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } else { rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)-1, (__u64)-1, device_number, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } if (!rc) { rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb, xid); if (pTcon->nocase) direntry->d_op = &cifs_ci_dentry_ops; else direntry->d_op = &cifs_dentry_ops; if (rc == 0) d_instantiate(direntry, newinode); } } else { if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) { int oplock = 0; u16 fileHandle; FILE_ALL_INFO *buf; cFYI(1, ("sfu compat create special file")); buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL); if (buf == NULL) { kfree(full_path); FreeXid(xid); return -ENOMEM; } rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_CREATE, /* fail if exists */ GENERIC_WRITE /* BB would WRITE_OWNER | WRITE_DAC be better? */, /* Create a file and set the file attribute to SYSTEM */ CREATE_NOT_DIR | CREATE_OPTION_SPECIAL, &fileHandle, &oplock, buf, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); /* BB FIXME - add handling for backlevel servers which need legacy open and check for all calls to SMBOpen for fallback to SMBLeagcyOpen */ if (!rc) { /* BB Do not bother to decode buf since no local inode yet to put timestamps in, but we can reuse it safely */ unsigned int bytes_written; struct win_dev *pdev; pdev = (struct win_dev *)buf; 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, pTcon, fileHandle, sizeof(struct win_dev), 0, &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, pTcon, fileHandle, sizeof(struct win_dev), 0, &bytes_written, (char *)pdev, NULL, 0); } /* else if(S_ISFIFO */ CIFSSMBClose(xid, pTcon, fileHandle); d_drop(direntry); } kfree(buf); /* add code here to set EAs */ } } kfree(full_path); FreeXid(xid); return rc; } struct dentry * cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, struct nameidata *nd) { int xid; int rc = 0; /* to get around spurious gcc warning, set to zero here */ struct cifs_sb_info *cifs_sb; struct cifsTconInfo *pTcon; struct inode *newInode = NULL; char *full_path = NULL; xid = GetXid(); cFYI(1, (" parent inode = 0x%p name is: %s and dentry = 0x%p", parent_dir_inode, direntry->d_name.name, direntry)); /* check whether path exists */ cifs_sb = CIFS_SB(parent_dir_inode->i_sb); pTcon = cifs_sb->tcon; /* * Don't allow the separator character in a path component. * The VFS will not allow "/", but "\" is allowed by posix. */ if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) { int i; for (i = 0; i < direntry->d_name.len; i++) if (direntry->d_name.name[i] == '\\') { cFYI(1, ("Invalid file name")); FreeXid(xid); return ERR_PTR(-EINVAL); } } /* 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) { FreeXid(xid); return ERR_PTR(-ENOMEM); } if (direntry->d_inode != NULL) { cFYI(1, (" non-NULL inode in lookup")); } else { cFYI(1, (" NULL inode in lookup")); } cFYI(1, (" Full path: %s inode = 0x%p", 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)) { if (pTcon->nocase) direntry->d_op = &cifs_ci_dentry_ops; else direntry->d_op = &cifs_dentry_ops; 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; if (pTcon->nocase) direntry->d_op = &cifs_ci_dentry_ops; else direntry->d_op = &cifs_dentry_ops; 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) { cERROR(1, ("Unexpected lookup error %d", rc)); /* We special case check for Access Denied - since that is a common return code */ } kfree(full_path); FreeXid(xid); return ERR_PTR(rc); } static int cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd) { int isValid = 1; if (direntry->d_inode) { if (cifs_revalidate(direntry)) return 0; } else { cFYI(1, ("neg dentry 0x%p name = %s", direntry, direntry->d_name.name)); if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled) { d_drop(direntry); isValid = 0; } } return isValid; } /* static int cifs_d_delete(struct dentry *direntry) { int rc = 0; cFYI(1, ("In cifs d_delete, name = %s", direntry->d_name.name)); return rc; } */ struct dentry_operations cifs_dentry_ops = { .d_revalidate = cifs_d_revalidate, /* d_delete: cifs_d_delete, */ /* not needed except for debugging */ }; static int cifs_ci_hash(struct dentry *dentry, struct qstr *q) { struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_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(struct dentry *dentry, struct qstr *a, struct qstr *b) { struct nls_table *codepage = CIFS_SB(dentry->d_inode->i_sb)->local_nls; if ((a->len == b->len) && (nls_strnicmp(codepage, a->name, b->name, a->len) == 0)) { /* * To preserve case, don't let an existing negative dentry's * case take precedence. If a is not a negative dentry, this * should have no side effects */ memcpy((void *)a->name, b->name, a->len); return 0; } return 1; } struct dentry_operations cifs_ci_dentry_ops = { .d_revalidate = cifs_d_revalidate, .d_hash = cifs_ci_hash, .d_compare = cifs_ci_compare, };