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- /*
- * fs/cifs/file.c
- *
- * vfs operations that deal with files
- *
- * Copyright (C) International Business Machines Corp., 2002,2010
- * Author(s): Steve French (sfrench@us.ibm.com)
- * Jeremy Allison (jra@samba.org)
- *
- * 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/backing-dev.h>
- #include <linux/stat.h>
- #include <linux/fcntl.h>
- #include <linux/pagemap.h>
- #include <linux/pagevec.h>
- #include <linux/writeback.h>
- #include <linux/task_io_accounting_ops.h>
- #include <linux/delay.h>
- #include <linux/mount.h>
- #include <linux/slab.h>
- #include <linux/swap.h>
- #include <asm/div64.h>
- #include "cifsfs.h"
- #include "cifspdu.h"
- #include "cifsglob.h"
- #include "cifsproto.h"
- #include "cifs_unicode.h"
- #include "cifs_debug.h"
- #include "cifs_fs_sb.h"
- #include "fscache.h"
- static inline int cifs_convert_flags(unsigned int flags)
- {
- if ((flags & O_ACCMODE) == O_RDONLY)
- return GENERIC_READ;
- else if ((flags & O_ACCMODE) == O_WRONLY)
- return GENERIC_WRITE;
- else if ((flags & O_ACCMODE) == O_RDWR) {
- /* GENERIC_ALL is too much permission to request
- can cause unnecessary access denied on create */
- /* return GENERIC_ALL; */
- return (GENERIC_READ | GENERIC_WRITE);
- }
- return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
- FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
- FILE_READ_DATA);
- }
- static u32 cifs_posix_convert_flags(unsigned int flags)
- {
- u32 posix_flags = 0;
- if ((flags & O_ACCMODE) == O_RDONLY)
- posix_flags = SMB_O_RDONLY;
- else if ((flags & O_ACCMODE) == O_WRONLY)
- posix_flags = SMB_O_WRONLY;
- else if ((flags & O_ACCMODE) == O_RDWR)
- posix_flags = SMB_O_RDWR;
- if (flags & O_CREAT) {
- posix_flags |= SMB_O_CREAT;
- if (flags & O_EXCL)
- posix_flags |= SMB_O_EXCL;
- } else if (flags & O_EXCL)
- cifs_dbg(FYI, "Application %s pid %d has incorrectly set O_EXCL flag but not O_CREAT on file open. Ignoring O_EXCL\n",
- current->comm, current->tgid);
- if (flags & O_TRUNC)
- posix_flags |= SMB_O_TRUNC;
- /* be safe and imply O_SYNC for O_DSYNC */
- if (flags & O_DSYNC)
- posix_flags |= SMB_O_SYNC;
- if (flags & O_DIRECTORY)
- posix_flags |= SMB_O_DIRECTORY;
- if (flags & O_NOFOLLOW)
- posix_flags |= SMB_O_NOFOLLOW;
- if (flags & O_DIRECT)
- posix_flags |= SMB_O_DIRECT;
- return posix_flags;
- }
- static inline int cifs_get_disposition(unsigned int flags)
- {
- if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
- return FILE_CREATE;
- else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
- return FILE_OVERWRITE_IF;
- else if ((flags & O_CREAT) == O_CREAT)
- return FILE_OPEN_IF;
- else if ((flags & O_TRUNC) == O_TRUNC)
- return FILE_OVERWRITE;
- else
- return FILE_OPEN;
- }
- int cifs_posix_open(char *full_path, struct inode **pinode,
- struct super_block *sb, int mode, unsigned int f_flags,
- __u32 *poplock, __u16 *pnetfid, unsigned int xid)
- {
- int rc;
- FILE_UNIX_BASIC_INFO *presp_data;
- __u32 posix_flags = 0;
- struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
- struct cifs_fattr fattr;
- struct tcon_link *tlink;
- struct cifs_tcon *tcon;
- cifs_dbg(FYI, "posix open %s\n", full_path);
- presp_data = kzalloc(sizeof(FILE_UNIX_BASIC_INFO), GFP_KERNEL);
- if (presp_data == NULL)
- return -ENOMEM;
- tlink = cifs_sb_tlink(cifs_sb);
- if (IS_ERR(tlink)) {
- rc = PTR_ERR(tlink);
- goto posix_open_ret;
- }
- tcon = tlink_tcon(tlink);
- mode &= ~current_umask();
- posix_flags = cifs_posix_convert_flags(f_flags);
- rc = CIFSPOSIXCreate(xid, tcon, posix_flags, mode, pnetfid, presp_data,
- poplock, full_path, cifs_sb->local_nls,
- cifs_remap(cifs_sb));
- cifs_put_tlink(tlink);
- if (rc)
- goto posix_open_ret;
- if (presp_data->Type == cpu_to_le32(-1))
- goto posix_open_ret; /* open ok, caller does qpathinfo */
- if (!pinode)
- goto posix_open_ret; /* caller does not need info */
- cifs_unix_basic_to_fattr(&fattr, presp_data, cifs_sb);
- /* get new inode and set it up */
- if (*pinode == NULL) {
- cifs_fill_uniqueid(sb, &fattr);
- *pinode = cifs_iget(sb, &fattr);
- if (!*pinode) {
- rc = -ENOMEM;
- goto posix_open_ret;
- }
- } else {
- cifs_fattr_to_inode(*pinode, &fattr);
- }
- posix_open_ret:
- kfree(presp_data);
- return rc;
- }
- static int
- cifs_nt_open(char *full_path, struct inode *inode, struct cifs_sb_info *cifs_sb,
- struct cifs_tcon *tcon, unsigned int f_flags, __u32 *oplock,
- struct cifs_fid *fid, unsigned int xid)
- {
- int rc;
- int desired_access;
- int disposition;
- int create_options = CREATE_NOT_DIR;
- FILE_ALL_INFO *buf;
- struct TCP_Server_Info *server = tcon->ses->server;
- struct cifs_open_parms oparms;
- if (!server->ops->open)
- return -ENOSYS;
- desired_access = cifs_convert_flags(f_flags);
- /*********************************************************************
- * open flag mapping table:
- *
- * POSIX Flag CIFS Disposition
- * ---------- ----------------
- * O_CREAT FILE_OPEN_IF
- * O_CREAT | O_EXCL FILE_CREATE
- * O_CREAT | O_TRUNC FILE_OVERWRITE_IF
- * O_TRUNC FILE_OVERWRITE
- * none of the above FILE_OPEN
- *
- * Note that there is not a direct match between disposition
- * FILE_SUPERSEDE (ie create whether or not file exists although
- * O_CREAT | O_TRUNC is similar but truncates the existing
- * file rather than creating a new file as FILE_SUPERSEDE does
- * (which uses the attributes / metadata passed in on open call)
- *?
- *? O_SYNC is a reasonable match to CIFS writethrough flag
- *? and the read write flags match reasonably. O_LARGEFILE
- *? is irrelevant because largefile support is always used
- *? by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
- * O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
- *********************************************************************/
- disposition = cifs_get_disposition(f_flags);
- /* BB pass O_SYNC flag through on file attributes .. BB */
- buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- if (backup_cred(cifs_sb))
- create_options |= CREATE_OPEN_BACKUP_INTENT;
- /* O_SYNC also has bit for O_DSYNC so following check picks up either */
- if (f_flags & O_SYNC)
- create_options |= CREATE_WRITE_THROUGH;
- if (f_flags & O_DIRECT)
- create_options |= CREATE_NO_BUFFER;
- 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;
- oparms.reconnect = false;
- rc = server->ops->open(xid, &oparms, oplock, buf);
- if (rc)
- goto out;
- if (tcon->unix_ext)
- rc = cifs_get_inode_info_unix(&inode, full_path, inode->i_sb,
- xid);
- else
- rc = cifs_get_inode_info(&inode, full_path, buf, inode->i_sb,
- xid, fid);
- out:
- kfree(buf);
- return rc;
- }
- static bool
- cifs_has_mand_locks(struct cifsInodeInfo *cinode)
- {
- struct cifs_fid_locks *cur;
- bool has_locks = false;
- down_read(&cinode->lock_sem);
- list_for_each_entry(cur, &cinode->llist, llist) {
- if (!list_empty(&cur->locks)) {
- has_locks = true;
- break;
- }
- }
- up_read(&cinode->lock_sem);
- return has_locks;
- }
- struct cifsFileInfo *
- cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
- struct tcon_link *tlink, __u32 oplock)
- {
- struct dentry *dentry = file_dentry(file);
- struct inode *inode = d_inode(dentry);
- struct cifsInodeInfo *cinode = CIFS_I(inode);
- struct cifsFileInfo *cfile;
- struct cifs_fid_locks *fdlocks;
- struct cifs_tcon *tcon = tlink_tcon(tlink);
- struct TCP_Server_Info *server = tcon->ses->server;
- cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
- if (cfile == NULL)
- return cfile;
- fdlocks = kzalloc(sizeof(struct cifs_fid_locks), GFP_KERNEL);
- if (!fdlocks) {
- kfree(cfile);
- return NULL;
- }
- INIT_LIST_HEAD(&fdlocks->locks);
- fdlocks->cfile = cfile;
- cfile->llist = fdlocks;
- down_write(&cinode->lock_sem);
- list_add(&fdlocks->llist, &cinode->llist);
- up_write(&cinode->lock_sem);
- cfile->count = 1;
- cfile->pid = current->tgid;
- cfile->uid = current_fsuid();
- cfile->dentry = dget(dentry);
- cfile->f_flags = file->f_flags;
- cfile->invalidHandle = false;
- cfile->tlink = cifs_get_tlink(tlink);
- INIT_WORK(&cfile->oplock_break, cifs_oplock_break);
- mutex_init(&cfile->fh_mutex);
- spin_lock_init(&cfile->file_info_lock);
- cifs_sb_active(inode->i_sb);
- /*
- * If the server returned a read oplock and we have mandatory brlocks,
- * set oplock level to None.
- */
- if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
- cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
- oplock = 0;
- }
- spin_lock(&tcon->open_file_lock);
- if (fid->pending_open->oplock != CIFS_OPLOCK_NO_CHANGE && oplock)
- oplock = fid->pending_open->oplock;
- list_del(&fid->pending_open->olist);
- fid->purge_cache = false;
- server->ops->set_fid(cfile, fid, oplock);
- list_add(&cfile->tlist, &tcon->openFileList);
- /* if readable file instance put first in list*/
- if (file->f_mode & FMODE_READ)
- list_add(&cfile->flist, &cinode->openFileList);
- else
- list_add_tail(&cfile->flist, &cinode->openFileList);
- spin_unlock(&tcon->open_file_lock);
- if (fid->purge_cache)
- cifs_zap_mapping(inode);
- file->private_data = cfile;
- return cfile;
- }
- struct cifsFileInfo *
- cifsFileInfo_get(struct cifsFileInfo *cifs_file)
- {
- spin_lock(&cifs_file->file_info_lock);
- cifsFileInfo_get_locked(cifs_file);
- spin_unlock(&cifs_file->file_info_lock);
- return cifs_file;
- }
- /*
- * Release a reference on the file private data. This may involve closing
- * the filehandle out on the server. Must be called without holding
- * tcon->open_file_lock and cifs_file->file_info_lock.
- */
- void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
- {
- struct inode *inode = d_inode(cifs_file->dentry);
- struct cifs_tcon *tcon = tlink_tcon(cifs_file->tlink);
- struct TCP_Server_Info *server = tcon->ses->server;
- struct cifsInodeInfo *cifsi = CIFS_I(inode);
- struct super_block *sb = inode->i_sb;
- struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
- struct cifsLockInfo *li, *tmp;
- struct cifs_fid fid;
- struct cifs_pending_open open;
- bool oplock_break_cancelled;
- spin_lock(&tcon->open_file_lock);
- spin_lock(&cifs_file->file_info_lock);
- if (--cifs_file->count > 0) {
- spin_unlock(&cifs_file->file_info_lock);
- spin_unlock(&tcon->open_file_lock);
- return;
- }
- spin_unlock(&cifs_file->file_info_lock);
- if (server->ops->get_lease_key)
- server->ops->get_lease_key(inode, &fid);
- /* store open in pending opens to make sure we don't miss lease break */
- cifs_add_pending_open_locked(&fid, cifs_file->tlink, &open);
- /* remove it from the lists */
- list_del(&cifs_file->flist);
- list_del(&cifs_file->tlist);
- if (list_empty(&cifsi->openFileList)) {
- cifs_dbg(FYI, "closing last open instance for inode %p\n",
- d_inode(cifs_file->dentry));
- /*
- * In strict cache mode we need invalidate mapping on the last
- * close because it may cause a error when we open this file
- * again and get at least level II oplock.
- */
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO)
- set_bit(CIFS_INO_INVALID_MAPPING, &cifsi->flags);
- cifs_set_oplock_level(cifsi, 0);
- }
- spin_unlock(&tcon->open_file_lock);
- oplock_break_cancelled = cancel_work_sync(&cifs_file->oplock_break);
- if (!tcon->need_reconnect && !cifs_file->invalidHandle) {
- struct TCP_Server_Info *server = tcon->ses->server;
- unsigned int xid;
- xid = get_xid();
- if (server->ops->close)
- server->ops->close(xid, tcon, &cifs_file->fid);
- _free_xid(xid);
- }
- if (oplock_break_cancelled)
- cifs_done_oplock_break(cifsi);
- cifs_del_pending_open(&open);
- /*
- * Delete any outstanding lock records. We'll lose them when the file
- * is closed anyway.
- */
- down_write(&cifsi->lock_sem);
- list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
- list_del(&li->llist);
- cifs_del_lock_waiters(li);
- kfree(li);
- }
- list_del(&cifs_file->llist->llist);
- kfree(cifs_file->llist);
- up_write(&cifsi->lock_sem);
- cifs_put_tlink(cifs_file->tlink);
- dput(cifs_file->dentry);
- cifs_sb_deactive(sb);
- kfree(cifs_file);
- }
- int cifs_open(struct inode *inode, struct file *file)
- {
- int rc = -EACCES;
- unsigned int xid;
- __u32 oplock;
- struct cifs_sb_info *cifs_sb;
- struct TCP_Server_Info *server;
- struct cifs_tcon *tcon;
- struct tcon_link *tlink;
- struct cifsFileInfo *cfile = NULL;
- char *full_path = NULL;
- bool posix_open_ok = false;
- struct cifs_fid fid;
- struct cifs_pending_open open;
- xid = get_xid();
- cifs_sb = CIFS_SB(inode->i_sb);
- tlink = cifs_sb_tlink(cifs_sb);
- if (IS_ERR(tlink)) {
- free_xid(xid);
- return PTR_ERR(tlink);
- }
- tcon = tlink_tcon(tlink);
- server = tcon->ses->server;
- full_path = build_path_from_dentry(file_dentry(file));
- if (full_path == NULL) {
- rc = -ENOMEM;
- goto out;
- }
- cifs_dbg(FYI, "inode = 0x%p file flags are 0x%x for %s\n",
- inode, file->f_flags, full_path);
- if (file->f_flags & O_DIRECT &&
- cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
- file->f_op = &cifs_file_direct_nobrl_ops;
- else
- file->f_op = &cifs_file_direct_ops;
- }
- if (server->oplocks)
- oplock = REQ_OPLOCK;
- else
- oplock = 0;
- if (!tcon->broken_posix_open && tcon->unix_ext &&
- cap_unix(tcon->ses) && (CIFS_UNIX_POSIX_PATH_OPS_CAP &
- le64_to_cpu(tcon->fsUnixInfo.Capability))) {
- /* can not refresh inode info since size could be stale */
- rc = cifs_posix_open(full_path, &inode, inode->i_sb,
- cifs_sb->mnt_file_mode /* ignored */,
- file->f_flags, &oplock, &fid.netfid, xid);
- if (rc == 0) {
- cifs_dbg(FYI, "posix open succeeded\n");
- posix_open_ok = true;
- } else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
- if (tcon->ses->serverNOS)
- cifs_dbg(VFS, "server %s of type %s returned unexpected error on SMB posix open, disabling posix open support. Check if server update available.\n",
- tcon->ses->serverName,
- tcon->ses->serverNOS);
- tcon->broken_posix_open = true;
- } else if ((rc != -EIO) && (rc != -EREMOTE) &&
- (rc != -EOPNOTSUPP)) /* path not found or net err */
- goto out;
- /*
- * Else fallthrough to retry open the old way on network i/o
- * or DFS errors.
- */
- }
- if (server->ops->get_lease_key)
- server->ops->get_lease_key(inode, &fid);
- cifs_add_pending_open(&fid, tlink, &open);
- if (!posix_open_ok) {
- if (server->ops->get_lease_key)
- server->ops->get_lease_key(inode, &fid);
- rc = cifs_nt_open(full_path, inode, cifs_sb, tcon,
- file->f_flags, &oplock, &fid, xid);
- if (rc) {
- cifs_del_pending_open(&open);
- goto out;
- }
- }
- cfile = cifs_new_fileinfo(&fid, file, tlink, oplock);
- if (cfile == NULL) {
- if (server->ops->close)
- server->ops->close(xid, tcon, &fid);
- cifs_del_pending_open(&open);
- rc = -ENOMEM;
- goto out;
- }
- cifs_fscache_set_inode_cookie(inode, file);
- if ((oplock & CIFS_CREATE_ACTION) && !posix_open_ok && tcon->unix_ext) {
- /*
- * Time to set mode which we can not set earlier due to
- * problems creating new read-only files.
- */
- struct cifs_unix_set_info_args args = {
- .mode = inode->i_mode,
- .uid = INVALID_UID, /* no change */
- .gid = INVALID_GID, /* no change */
- .ctime = NO_CHANGE_64,
- .atime = NO_CHANGE_64,
- .mtime = NO_CHANGE_64,
- .device = 0,
- };
- CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid.netfid,
- cfile->pid);
- }
- out:
- kfree(full_path);
- free_xid(xid);
- cifs_put_tlink(tlink);
- return rc;
- }
- static int cifs_push_posix_locks(struct cifsFileInfo *cfile);
- /*
- * Try to reacquire byte range locks that were released when session
- * to server was lost.
- */
- static int
- cifs_relock_file(struct cifsFileInfo *cfile)
- {
- struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- int rc = 0;
- down_read_nested(&cinode->lock_sem, SINGLE_DEPTH_NESTING);
- if (cinode->can_cache_brlcks) {
- /* can cache locks - no need to relock */
- up_read(&cinode->lock_sem);
- return rc;
- }
- if (cap_unix(tcon->ses) &&
- (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
- ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
- rc = cifs_push_posix_locks(cfile);
- else
- rc = tcon->ses->server->ops->push_mand_locks(cfile);
- up_read(&cinode->lock_sem);
- return rc;
- }
- static int
- cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush)
- {
- int rc = -EACCES;
- unsigned int xid;
- __u32 oplock;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- struct cifsInodeInfo *cinode;
- struct inode *inode;
- char *full_path = NULL;
- int desired_access;
- int disposition = FILE_OPEN;
- int create_options = CREATE_NOT_DIR;
- struct cifs_open_parms oparms;
- xid = get_xid();
- mutex_lock(&cfile->fh_mutex);
- if (!cfile->invalidHandle) {
- mutex_unlock(&cfile->fh_mutex);
- rc = 0;
- free_xid(xid);
- return rc;
- }
- inode = d_inode(cfile->dentry);
- cifs_sb = CIFS_SB(inode->i_sb);
- tcon = tlink_tcon(cfile->tlink);
- server = tcon->ses->server;
- /*
- * Can not grab rename sem here because various ops, including those
- * that already have the rename sem can end up causing writepage to get
- * called and if the server was down that means we end up here, and we
- * can never tell if the caller already has the rename_sem.
- */
- full_path = build_path_from_dentry(cfile->dentry);
- if (full_path == NULL) {
- rc = -ENOMEM;
- mutex_unlock(&cfile->fh_mutex);
- free_xid(xid);
- return rc;
- }
- cifs_dbg(FYI, "inode = 0x%p file flags 0x%x for %s\n",
- inode, cfile->f_flags, full_path);
- if (tcon->ses->server->oplocks)
- oplock = REQ_OPLOCK;
- else
- oplock = 0;
- if (tcon->unix_ext && cap_unix(tcon->ses) &&
- (CIFS_UNIX_POSIX_PATH_OPS_CAP &
- le64_to_cpu(tcon->fsUnixInfo.Capability))) {
- /*
- * O_CREAT, O_EXCL and O_TRUNC already had their effect on the
- * original open. Must mask them off for a reopen.
- */
- unsigned int oflags = cfile->f_flags &
- ~(O_CREAT | O_EXCL | O_TRUNC);
- rc = cifs_posix_open(full_path, NULL, inode->i_sb,
- cifs_sb->mnt_file_mode /* ignored */,
- oflags, &oplock, &cfile->fid.netfid, xid);
- if (rc == 0) {
- cifs_dbg(FYI, "posix reopen succeeded\n");
- oparms.reconnect = true;
- goto reopen_success;
- }
- /*
- * fallthrough to retry open the old way on errors, especially
- * in the reconnect path it is important to retry hard
- */
- }
- desired_access = cifs_convert_flags(cfile->f_flags);
- if (backup_cred(cifs_sb))
- create_options |= CREATE_OPEN_BACKUP_INTENT;
- if (server->ops->get_lease_key)
- server->ops->get_lease_key(inode, &cfile->fid);
- 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 = &cfile->fid;
- oparms.reconnect = true;
- /*
- * Can not refresh inode by passing in file_info buf to be returned by
- * ops->open and then calling get_inode_info with returned buf since
- * file might have write behind data that needs to be flushed and server
- * version of file size can be stale. If we knew for sure that inode was
- * not dirty locally we could do this.
- */
- rc = server->ops->open(xid, &oparms, &oplock, NULL);
- if (rc == -ENOENT && oparms.reconnect == false) {
- /* durable handle timeout is expired - open the file again */
- rc = server->ops->open(xid, &oparms, &oplock, NULL);
- /* indicate that we need to relock the file */
- oparms.reconnect = true;
- }
- if (rc) {
- mutex_unlock(&cfile->fh_mutex);
- cifs_dbg(FYI, "cifs_reopen returned 0x%x\n", rc);
- cifs_dbg(FYI, "oplock: %d\n", oplock);
- goto reopen_error_exit;
- }
- reopen_success:
- cfile->invalidHandle = false;
- mutex_unlock(&cfile->fh_mutex);
- cinode = CIFS_I(inode);
- if (can_flush) {
- rc = filemap_write_and_wait(inode->i_mapping);
- mapping_set_error(inode->i_mapping, rc);
- if (tcon->unix_ext)
- rc = cifs_get_inode_info_unix(&inode, full_path,
- inode->i_sb, xid);
- else
- rc = cifs_get_inode_info(&inode, full_path, NULL,
- inode->i_sb, xid, NULL);
- }
- /*
- * Else we are writing out data to server already and could deadlock if
- * we tried to flush data, and since we do not know if we have data that
- * would invalidate the current end of file on the server we can not go
- * to the server to get the new inode info.
- */
- /*
- * If the server returned a read oplock and we have mandatory brlocks,
- * set oplock level to None.
- */
- if (server->ops->is_read_op(oplock) && cifs_has_mand_locks(cinode)) {
- cifs_dbg(FYI, "Reset oplock val from read to None due to mand locks\n");
- oplock = 0;
- }
- server->ops->set_fid(cfile, &cfile->fid, oplock);
- if (oparms.reconnect)
- cifs_relock_file(cfile);
- reopen_error_exit:
- kfree(full_path);
- free_xid(xid);
- return rc;
- }
- int cifs_close(struct inode *inode, struct file *file)
- {
- if (file->private_data != NULL) {
- cifsFileInfo_put(file->private_data);
- file->private_data = NULL;
- }
- /* return code from the ->release op is always ignored */
- return 0;
- }
- void
- cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
- {
- struct cifsFileInfo *open_file;
- struct list_head *tmp;
- struct list_head *tmp1;
- struct list_head tmp_list;
- if (!tcon->use_persistent || !tcon->need_reopen_files)
- return;
- tcon->need_reopen_files = false;
- cifs_dbg(FYI, "Reopen persistent handles");
- INIT_LIST_HEAD(&tmp_list);
- /* list all files open on tree connection, reopen resilient handles */
- spin_lock(&tcon->open_file_lock);
- list_for_each(tmp, &tcon->openFileList) {
- open_file = list_entry(tmp, struct cifsFileInfo, tlist);
- if (!open_file->invalidHandle)
- continue;
- cifsFileInfo_get(open_file);
- list_add_tail(&open_file->rlist, &tmp_list);
- }
- spin_unlock(&tcon->open_file_lock);
- list_for_each_safe(tmp, tmp1, &tmp_list) {
- open_file = list_entry(tmp, struct cifsFileInfo, rlist);
- if (cifs_reopen_file(open_file, false /* do not flush */))
- tcon->need_reopen_files = true;
- list_del_init(&open_file->rlist);
- cifsFileInfo_put(open_file);
- }
- }
- int cifs_closedir(struct inode *inode, struct file *file)
- {
- int rc = 0;
- unsigned int xid;
- struct cifsFileInfo *cfile = file->private_data;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- char *buf;
- cifs_dbg(FYI, "Closedir inode = 0x%p\n", inode);
- if (cfile == NULL)
- return rc;
- xid = get_xid();
- tcon = tlink_tcon(cfile->tlink);
- server = tcon->ses->server;
- cifs_dbg(FYI, "Freeing private data in close dir\n");
- spin_lock(&cfile->file_info_lock);
- if (server->ops->dir_needs_close(cfile)) {
- cfile->invalidHandle = true;
- spin_unlock(&cfile->file_info_lock);
- if (server->ops->close_dir)
- rc = server->ops->close_dir(xid, tcon, &cfile->fid);
- else
- rc = -ENOSYS;
- cifs_dbg(FYI, "Closing uncompleted readdir with rc %d\n", rc);
- /* not much we can do if it fails anyway, ignore rc */
- rc = 0;
- } else
- spin_unlock(&cfile->file_info_lock);
- buf = cfile->srch_inf.ntwrk_buf_start;
- if (buf) {
- cifs_dbg(FYI, "closedir free smb buf in srch struct\n");
- cfile->srch_inf.ntwrk_buf_start = NULL;
- if (cfile->srch_inf.smallBuf)
- cifs_small_buf_release(buf);
- else
- cifs_buf_release(buf);
- }
- cifs_put_tlink(cfile->tlink);
- kfree(file->private_data);
- file->private_data = NULL;
- /* BB can we lock the filestruct while this is going on? */
- free_xid(xid);
- return rc;
- }
- static struct cifsLockInfo *
- cifs_lock_init(__u64 offset, __u64 length, __u8 type)
- {
- struct cifsLockInfo *lock =
- kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
- if (!lock)
- return lock;
- lock->offset = offset;
- lock->length = length;
- lock->type = type;
- lock->pid = current->tgid;
- INIT_LIST_HEAD(&lock->blist);
- init_waitqueue_head(&lock->block_q);
- return lock;
- }
- void
- cifs_del_lock_waiters(struct cifsLockInfo *lock)
- {
- struct cifsLockInfo *li, *tmp;
- list_for_each_entry_safe(li, tmp, &lock->blist, blist) {
- list_del_init(&li->blist);
- wake_up(&li->block_q);
- }
- }
- #define CIFS_LOCK_OP 0
- #define CIFS_READ_OP 1
- #define CIFS_WRITE_OP 2
- /* @rw_check : 0 - no op, 1 - read, 2 - write */
- static bool
- cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
- __u64 length, __u8 type, struct cifsFileInfo *cfile,
- struct cifsLockInfo **conf_lock, int rw_check)
- {
- struct cifsLockInfo *li;
- struct cifsFileInfo *cur_cfile = fdlocks->cfile;
- struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
- list_for_each_entry(li, &fdlocks->locks, llist) {
- if (offset + length <= li->offset ||
- offset >= li->offset + li->length)
- continue;
- if (rw_check != CIFS_LOCK_OP && current->tgid == li->pid &&
- server->ops->compare_fids(cfile, cur_cfile)) {
- /* shared lock prevents write op through the same fid */
- if (!(li->type & server->vals->shared_lock_type) ||
- rw_check != CIFS_WRITE_OP)
- continue;
- }
- if ((type & server->vals->shared_lock_type) &&
- ((server->ops->compare_fids(cfile, cur_cfile) &&
- current->tgid == li->pid) || type == li->type))
- continue;
- if (conf_lock)
- *conf_lock = li;
- return true;
- }
- return false;
- }
- bool
- cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
- __u8 type, struct cifsLockInfo **conf_lock,
- int rw_check)
- {
- bool rc = false;
- struct cifs_fid_locks *cur;
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- list_for_each_entry(cur, &cinode->llist, llist) {
- rc = cifs_find_fid_lock_conflict(cur, offset, length, type,
- cfile, conf_lock, rw_check);
- if (rc)
- break;
- }
- return rc;
- }
- /*
- * Check if there is another lock that prevents us to set the lock (mandatory
- * style). If such a lock exists, update the flock structure with its
- * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
- * or leave it the same if we can't. Returns 0 if we don't need to request to
- * the server or 1 otherwise.
- */
- static int
- cifs_lock_test(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
- __u8 type, struct file_lock *flock)
- {
- int rc = 0;
- struct cifsLockInfo *conf_lock;
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
- bool exist;
- down_read(&cinode->lock_sem);
- exist = cifs_find_lock_conflict(cfile, offset, length, type,
- &conf_lock, CIFS_LOCK_OP);
- if (exist) {
- flock->fl_start = conf_lock->offset;
- flock->fl_end = conf_lock->offset + conf_lock->length - 1;
- flock->fl_pid = conf_lock->pid;
- if (conf_lock->type & server->vals->shared_lock_type)
- flock->fl_type = F_RDLCK;
- else
- flock->fl_type = F_WRLCK;
- } else if (!cinode->can_cache_brlcks)
- rc = 1;
- else
- flock->fl_type = F_UNLCK;
- up_read(&cinode->lock_sem);
- return rc;
- }
- static void
- cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock)
- {
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- down_write(&cinode->lock_sem);
- list_add_tail(&lock->llist, &cfile->llist->locks);
- up_write(&cinode->lock_sem);
- }
- /*
- * Set the byte-range lock (mandatory style). Returns:
- * 1) 0, if we set the lock and don't need to request to the server;
- * 2) 1, if no locks prevent us but we need to request to the server;
- * 3) -EACCESS, if there is a lock that prevents us and wait is false.
- */
- static int
- cifs_lock_add_if(struct cifsFileInfo *cfile, struct cifsLockInfo *lock,
- bool wait)
- {
- struct cifsLockInfo *conf_lock;
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- bool exist;
- int rc = 0;
- try_again:
- exist = false;
- down_write(&cinode->lock_sem);
- exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length,
- lock->type, &conf_lock, CIFS_LOCK_OP);
- if (!exist && cinode->can_cache_brlcks) {
- list_add_tail(&lock->llist, &cfile->llist->locks);
- up_write(&cinode->lock_sem);
- return rc;
- }
- if (!exist)
- rc = 1;
- else if (!wait)
- rc = -EACCES;
- else {
- list_add_tail(&lock->blist, &conf_lock->blist);
- up_write(&cinode->lock_sem);
- rc = wait_event_interruptible(lock->block_q,
- (lock->blist.prev == &lock->blist) &&
- (lock->blist.next == &lock->blist));
- if (!rc)
- goto try_again;
- down_write(&cinode->lock_sem);
- list_del_init(&lock->blist);
- }
- up_write(&cinode->lock_sem);
- return rc;
- }
- /*
- * Check if there is another lock that prevents us to set the lock (posix
- * style). If such a lock exists, update the flock structure with its
- * properties. Otherwise, set the flock type to F_UNLCK if we can cache brlocks
- * or leave it the same if we can't. Returns 0 if we don't need to request to
- * the server or 1 otherwise.
- */
- static int
- cifs_posix_lock_test(struct file *file, struct file_lock *flock)
- {
- int rc = 0;
- struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
- unsigned char saved_type = flock->fl_type;
- if ((flock->fl_flags & FL_POSIX) == 0)
- return 1;
- down_read(&cinode->lock_sem);
- posix_test_lock(file, flock);
- if (flock->fl_type == F_UNLCK && !cinode->can_cache_brlcks) {
- flock->fl_type = saved_type;
- rc = 1;
- }
- up_read(&cinode->lock_sem);
- return rc;
- }
- /*
- * Set the byte-range lock (posix style). Returns:
- * 1) 0, if we set the lock and don't need to request to the server;
- * 2) 1, if we need to request to the server;
- * 3) <0, if the error occurs while setting the lock.
- */
- static int
- cifs_posix_lock_set(struct file *file, struct file_lock *flock)
- {
- struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
- int rc = 1;
- if ((flock->fl_flags & FL_POSIX) == 0)
- return rc;
- try_again:
- down_write(&cinode->lock_sem);
- if (!cinode->can_cache_brlcks) {
- up_write(&cinode->lock_sem);
- return rc;
- }
- rc = posix_lock_file(file, flock, NULL);
- up_write(&cinode->lock_sem);
- if (rc == FILE_LOCK_DEFERRED) {
- rc = wait_event_interruptible(flock->fl_wait, !flock->fl_next);
- if (!rc)
- goto try_again;
- posix_unblock_lock(flock);
- }
- return rc;
- }
- int
- cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
- {
- unsigned int xid;
- int rc = 0, stored_rc;
- struct cifsLockInfo *li, *tmp;
- struct cifs_tcon *tcon;
- unsigned int num, max_num, max_buf;
- LOCKING_ANDX_RANGE *buf, *cur;
- int types[] = {LOCKING_ANDX_LARGE_FILES,
- LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES};
- int i;
- xid = get_xid();
- tcon = tlink_tcon(cfile->tlink);
- /*
- * Accessing maxBuf is racy with cifs_reconnect - need to store value
- * and check it for zero before using.
- */
- max_buf = tcon->ses->server->maxBuf;
- if (!max_buf) {
- free_xid(xid);
- return -EINVAL;
- }
- max_num = (max_buf - sizeof(struct smb_hdr)) /
- sizeof(LOCKING_ANDX_RANGE);
- buf = kcalloc(max_num, sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
- if (!buf) {
- free_xid(xid);
- return -ENOMEM;
- }
- for (i = 0; i < 2; i++) {
- cur = buf;
- num = 0;
- list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
- if (li->type != types[i])
- continue;
- cur->Pid = cpu_to_le16(li->pid);
- cur->LengthLow = cpu_to_le32((u32)li->length);
- cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
- cur->OffsetLow = cpu_to_le32((u32)li->offset);
- cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
- if (++num == max_num) {
- stored_rc = cifs_lockv(xid, tcon,
- cfile->fid.netfid,
- (__u8)li->type, 0, num,
- buf);
- if (stored_rc)
- rc = stored_rc;
- cur = buf;
- num = 0;
- } else
- cur++;
- }
- if (num) {
- stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
- (__u8)types[i], 0, num, buf);
- if (stored_rc)
- rc = stored_rc;
- }
- }
- kfree(buf);
- free_xid(xid);
- return rc;
- }
- static __u32
- hash_lockowner(fl_owner_t owner)
- {
- return cifs_lock_secret ^ hash32_ptr((const void *)owner);
- }
- struct lock_to_push {
- struct list_head llist;
- __u64 offset;
- __u64 length;
- __u32 pid;
- __u16 netfid;
- __u8 type;
- };
- static int
- cifs_push_posix_locks(struct cifsFileInfo *cfile)
- {
- struct inode *inode = d_inode(cfile->dentry);
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- struct file_lock *flock;
- struct file_lock_context *flctx = inode->i_flctx;
- unsigned int count = 0, i;
- int rc = 0, xid, type;
- struct list_head locks_to_send, *el;
- struct lock_to_push *lck, *tmp;
- __u64 length;
- xid = get_xid();
- if (!flctx)
- goto out;
- spin_lock(&flctx->flc_lock);
- list_for_each(el, &flctx->flc_posix) {
- count++;
- }
- spin_unlock(&flctx->flc_lock);
- INIT_LIST_HEAD(&locks_to_send);
- /*
- * Allocating count locks is enough because no FL_POSIX locks can be
- * added to the list while we are holding cinode->lock_sem that
- * protects locking operations of this inode.
- */
- for (i = 0; i < count; i++) {
- lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
- if (!lck) {
- rc = -ENOMEM;
- goto err_out;
- }
- list_add_tail(&lck->llist, &locks_to_send);
- }
- el = locks_to_send.next;
- spin_lock(&flctx->flc_lock);
- list_for_each_entry(flock, &flctx->flc_posix, fl_list) {
- if (el == &locks_to_send) {
- /*
- * The list ended. We don't have enough allocated
- * structures - something is really wrong.
- */
- cifs_dbg(VFS, "Can't push all brlocks!\n");
- break;
- }
- length = 1 + flock->fl_end - flock->fl_start;
- if (flock->fl_type == F_RDLCK || flock->fl_type == F_SHLCK)
- type = CIFS_RDLCK;
- else
- type = CIFS_WRLCK;
- lck = list_entry(el, struct lock_to_push, llist);
- lck->pid = hash_lockowner(flock->fl_owner);
- lck->netfid = cfile->fid.netfid;
- lck->length = length;
- lck->type = type;
- lck->offset = flock->fl_start;
- }
- spin_unlock(&flctx->flc_lock);
- list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
- int stored_rc;
- stored_rc = CIFSSMBPosixLock(xid, tcon, lck->netfid, lck->pid,
- lck->offset, lck->length, NULL,
- lck->type, 0);
- if (stored_rc)
- rc = stored_rc;
- list_del(&lck->llist);
- kfree(lck);
- }
- out:
- free_xid(xid);
- return rc;
- err_out:
- list_for_each_entry_safe(lck, tmp, &locks_to_send, llist) {
- list_del(&lck->llist);
- kfree(lck);
- }
- goto out;
- }
- static int
- cifs_push_locks(struct cifsFileInfo *cfile)
- {
- struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- int rc = 0;
- /* we are going to update can_cache_brlcks here - need a write access */
- down_write(&cinode->lock_sem);
- if (!cinode->can_cache_brlcks) {
- up_write(&cinode->lock_sem);
- return rc;
- }
- if (cap_unix(tcon->ses) &&
- (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
- ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
- rc = cifs_push_posix_locks(cfile);
- else
- rc = tcon->ses->server->ops->push_mand_locks(cfile);
- cinode->can_cache_brlcks = false;
- up_write(&cinode->lock_sem);
- return rc;
- }
- static void
- cifs_read_flock(struct file_lock *flock, __u32 *type, int *lock, int *unlock,
- bool *wait_flag, struct TCP_Server_Info *server)
- {
- if (flock->fl_flags & FL_POSIX)
- cifs_dbg(FYI, "Posix\n");
- if (flock->fl_flags & FL_FLOCK)
- cifs_dbg(FYI, "Flock\n");
- if (flock->fl_flags & FL_SLEEP) {
- cifs_dbg(FYI, "Blocking lock\n");
- *wait_flag = true;
- }
- if (flock->fl_flags & FL_ACCESS)
- cifs_dbg(FYI, "Process suspended by mandatory locking - not implemented yet\n");
- if (flock->fl_flags & FL_LEASE)
- cifs_dbg(FYI, "Lease on file - not implemented yet\n");
- if (flock->fl_flags &
- (~(FL_POSIX | FL_FLOCK | FL_SLEEP |
- FL_ACCESS | FL_LEASE | FL_CLOSE)))
- cifs_dbg(FYI, "Unknown lock flags 0x%x\n", flock->fl_flags);
- *type = server->vals->large_lock_type;
- if (flock->fl_type == F_WRLCK) {
- cifs_dbg(FYI, "F_WRLCK\n");
- *type |= server->vals->exclusive_lock_type;
- *lock = 1;
- } else if (flock->fl_type == F_UNLCK) {
- cifs_dbg(FYI, "F_UNLCK\n");
- *type |= server->vals->unlock_lock_type;
- *unlock = 1;
- /* Check if unlock includes more than one lock range */
- } else if (flock->fl_type == F_RDLCK) {
- cifs_dbg(FYI, "F_RDLCK\n");
- *type |= server->vals->shared_lock_type;
- *lock = 1;
- } else if (flock->fl_type == F_EXLCK) {
- cifs_dbg(FYI, "F_EXLCK\n");
- *type |= server->vals->exclusive_lock_type;
- *lock = 1;
- } else if (flock->fl_type == F_SHLCK) {
- cifs_dbg(FYI, "F_SHLCK\n");
- *type |= server->vals->shared_lock_type;
- *lock = 1;
- } else
- cifs_dbg(FYI, "Unknown type of lock\n");
- }
- static int
- cifs_getlk(struct file *file, struct file_lock *flock, __u32 type,
- bool wait_flag, bool posix_lck, unsigned int xid)
- {
- int rc = 0;
- __u64 length = 1 + flock->fl_end - flock->fl_start;
- struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- struct TCP_Server_Info *server = tcon->ses->server;
- __u16 netfid = cfile->fid.netfid;
- if (posix_lck) {
- int posix_lock_type;
- rc = cifs_posix_lock_test(file, flock);
- if (!rc)
- return rc;
- if (type & server->vals->shared_lock_type)
- posix_lock_type = CIFS_RDLCK;
- else
- posix_lock_type = CIFS_WRLCK;
- rc = CIFSSMBPosixLock(xid, tcon, netfid,
- hash_lockowner(flock->fl_owner),
- flock->fl_start, length, flock,
- posix_lock_type, wait_flag);
- return rc;
- }
- rc = cifs_lock_test(cfile, flock->fl_start, length, type, flock);
- if (!rc)
- return rc;
- /* BB we could chain these into one lock request BB */
- rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length, type,
- 1, 0, false);
- if (rc == 0) {
- rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
- type, 0, 1, false);
- flock->fl_type = F_UNLCK;
- if (rc != 0)
- cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
- rc);
- return 0;
- }
- if (type & server->vals->shared_lock_type) {
- flock->fl_type = F_WRLCK;
- return 0;
- }
- type &= ~server->vals->exclusive_lock_type;
- rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
- type | server->vals->shared_lock_type,
- 1, 0, false);
- if (rc == 0) {
- rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
- type | server->vals->shared_lock_type, 0, 1, false);
- flock->fl_type = F_RDLCK;
- if (rc != 0)
- cifs_dbg(VFS, "Error unlocking previously locked range %d during test of lock\n",
- rc);
- } else
- flock->fl_type = F_WRLCK;
- return 0;
- }
- void
- cifs_move_llist(struct list_head *source, struct list_head *dest)
- {
- struct list_head *li, *tmp;
- list_for_each_safe(li, tmp, source)
- list_move(li, dest);
- }
- void
- cifs_free_llist(struct list_head *llist)
- {
- struct cifsLockInfo *li, *tmp;
- list_for_each_entry_safe(li, tmp, llist, llist) {
- cifs_del_lock_waiters(li);
- list_del(&li->llist);
- kfree(li);
- }
- }
- int
- cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
- unsigned int xid)
- {
- int rc = 0, stored_rc;
- int types[] = {LOCKING_ANDX_LARGE_FILES,
- LOCKING_ANDX_SHARED_LOCK | LOCKING_ANDX_LARGE_FILES};
- unsigned int i;
- unsigned int max_num, num, max_buf;
- LOCKING_ANDX_RANGE *buf, *cur;
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
- struct cifsLockInfo *li, *tmp;
- __u64 length = 1 + flock->fl_end - flock->fl_start;
- struct list_head tmp_llist;
- INIT_LIST_HEAD(&tmp_llist);
- /*
- * Accessing maxBuf is racy with cifs_reconnect - need to store value
- * and check it for zero before using.
- */
- max_buf = tcon->ses->server->maxBuf;
- if (!max_buf)
- return -EINVAL;
- max_num = (max_buf - sizeof(struct smb_hdr)) /
- sizeof(LOCKING_ANDX_RANGE);
- buf = kcalloc(max_num, sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- down_write(&cinode->lock_sem);
- for (i = 0; i < 2; i++) {
- cur = buf;
- num = 0;
- list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
- if (flock->fl_start > li->offset ||
- (flock->fl_start + length) <
- (li->offset + li->length))
- continue;
- if (current->tgid != li->pid)
- continue;
- if (types[i] != li->type)
- continue;
- if (cinode->can_cache_brlcks) {
- /*
- * We can cache brlock requests - simply remove
- * a lock from the file's list.
- */
- list_del(&li->llist);
- cifs_del_lock_waiters(li);
- kfree(li);
- continue;
- }
- cur->Pid = cpu_to_le16(li->pid);
- cur->LengthLow = cpu_to_le32((u32)li->length);
- cur->LengthHigh = cpu_to_le32((u32)(li->length>>32));
- cur->OffsetLow = cpu_to_le32((u32)li->offset);
- cur->OffsetHigh = cpu_to_le32((u32)(li->offset>>32));
- /*
- * We need to save a lock here to let us add it again to
- * the file's list if the unlock range request fails on
- * the server.
- */
- list_move(&li->llist, &tmp_llist);
- if (++num == max_num) {
- stored_rc = cifs_lockv(xid, tcon,
- cfile->fid.netfid,
- li->type, num, 0, buf);
- if (stored_rc) {
- /*
- * We failed on the unlock range
- * request - add all locks from the tmp
- * list to the head of the file's list.
- */
- cifs_move_llist(&tmp_llist,
- &cfile->llist->locks);
- rc = stored_rc;
- } else
- /*
- * The unlock range request succeed -
- * free the tmp list.
- */
- cifs_free_llist(&tmp_llist);
- cur = buf;
- num = 0;
- } else
- cur++;
- }
- if (num) {
- stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid,
- types[i], num, 0, buf);
- if (stored_rc) {
- cifs_move_llist(&tmp_llist,
- &cfile->llist->locks);
- rc = stored_rc;
- } else
- cifs_free_llist(&tmp_llist);
- }
- }
- up_write(&cinode->lock_sem);
- kfree(buf);
- return rc;
- }
- static int
- cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
- bool wait_flag, bool posix_lck, int lock, int unlock,
- unsigned int xid)
- {
- int rc = 0;
- __u64 length = 1 + flock->fl_end - flock->fl_start;
- struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- struct TCP_Server_Info *server = tcon->ses->server;
- struct inode *inode = d_inode(cfile->dentry);
- if (posix_lck) {
- int posix_lock_type;
- rc = cifs_posix_lock_set(file, flock);
- if (!rc || rc < 0)
- return rc;
- if (type & server->vals->shared_lock_type)
- posix_lock_type = CIFS_RDLCK;
- else
- posix_lock_type = CIFS_WRLCK;
- if (unlock == 1)
- posix_lock_type = CIFS_UNLCK;
- rc = CIFSSMBPosixLock(xid, tcon, cfile->fid.netfid,
- hash_lockowner(flock->fl_owner),
- flock->fl_start, length,
- NULL, posix_lock_type, wait_flag);
- goto out;
- }
- if (lock) {
- struct cifsLockInfo *lock;
- lock = cifs_lock_init(flock->fl_start, length, type);
- if (!lock)
- return -ENOMEM;
- rc = cifs_lock_add_if(cfile, lock, wait_flag);
- if (rc < 0) {
- kfree(lock);
- return rc;
- }
- if (!rc)
- goto out;
- /*
- * Windows 7 server can delay breaking lease from read to None
- * if we set a byte-range lock on a file - break it explicitly
- * before sending the lock to the server to be sure the next
- * read won't conflict with non-overlapted locks due to
- * pagereading.
- */
- if (!CIFS_CACHE_WRITE(CIFS_I(inode)) &&
- CIFS_CACHE_READ(CIFS_I(inode))) {
- cifs_zap_mapping(inode);
- cifs_dbg(FYI, "Set no oplock for inode=%p due to mand locks\n",
- inode);
- CIFS_I(inode)->oplock = 0;
- }
- rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
- type, 1, 0, wait_flag);
- if (rc) {
- kfree(lock);
- return rc;
- }
- cifs_lock_add(cfile, lock);
- } else if (unlock)
- rc = server->ops->mand_unlock_range(cfile, flock, xid);
- out:
- if (flock->fl_flags & FL_POSIX && !rc)
- rc = locks_lock_file_wait(file, flock);
- return rc;
- }
- int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
- {
- int rc, xid;
- int lock = 0, unlock = 0;
- bool wait_flag = false;
- bool posix_lck = false;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- struct cifsInodeInfo *cinode;
- struct cifsFileInfo *cfile;
- __u16 netfid;
- __u32 type;
- rc = -EACCES;
- xid = get_xid();
- cifs_dbg(FYI, "Lock parm: 0x%x flockflags: 0x%x flocktype: 0x%x start: %lld end: %lld\n",
- cmd, flock->fl_flags, flock->fl_type,
- flock->fl_start, flock->fl_end);
- cfile = (struct cifsFileInfo *)file->private_data;
- tcon = tlink_tcon(cfile->tlink);
- cifs_read_flock(flock, &type, &lock, &unlock, &wait_flag,
- tcon->ses->server);
- cifs_sb = CIFS_FILE_SB(file);
- netfid = cfile->fid.netfid;
- cinode = CIFS_I(file_inode(file));
- if (cap_unix(tcon->ses) &&
- (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
- ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
- posix_lck = true;
- /*
- * BB add code here to normalize offset and length to account for
- * negative length which we can not accept over the wire.
- */
- if (IS_GETLK(cmd)) {
- rc = cifs_getlk(file, flock, type, wait_flag, posix_lck, xid);
- free_xid(xid);
- return rc;
- }
- if (!lock && !unlock) {
- /*
- * if no lock or unlock then nothing to do since we do not
- * know what it is
- */
- free_xid(xid);
- return -EOPNOTSUPP;
- }
- rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock,
- xid);
- free_xid(xid);
- return rc;
- }
- /*
- * update the file size (if needed) after a write. Should be called with
- * the inode->i_lock held
- */
- void
- cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
- unsigned int bytes_written)
- {
- loff_t end_of_write = offset + bytes_written;
- if (end_of_write > cifsi->server_eof)
- cifsi->server_eof = end_of_write;
- }
- static ssize_t
- cifs_write(struct cifsFileInfo *open_file, __u32 pid, const char *write_data,
- size_t write_size, loff_t *offset)
- {
- int rc = 0;
- unsigned int bytes_written = 0;
- unsigned int total_written;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- unsigned int xid;
- struct dentry *dentry = open_file->dentry;
- struct cifsInodeInfo *cifsi = CIFS_I(d_inode(dentry));
- struct cifs_io_parms io_parms;
- cifs_sb = CIFS_SB(dentry->d_sb);
- cifs_dbg(FYI, "write %zd bytes to offset %lld of %pd\n",
- write_size, *offset, dentry);
- tcon = tlink_tcon(open_file->tlink);
- server = tcon->ses->server;
- if (!server->ops->sync_write)
- return -ENOSYS;
- xid = get_xid();
- for (total_written = 0; write_size > total_written;
- total_written += bytes_written) {
- rc = -EAGAIN;
- while (rc == -EAGAIN) {
- struct kvec iov[2];
- unsigned int len;
- if (open_file->invalidHandle) {
- /* we could deadlock if we called
- filemap_fdatawait from here so tell
- reopen_file not to flush data to
- server now */
- rc = cifs_reopen_file(open_file, false);
- if (rc != 0)
- break;
- }
- len = min(server->ops->wp_retry_size(d_inode(dentry)),
- (unsigned int)write_size - total_written);
- /* iov[0] is reserved for smb header */
- iov[1].iov_base = (char *)write_data + total_written;
- iov[1].iov_len = len;
- io_parms.pid = pid;
- io_parms.tcon = tcon;
- io_parms.offset = *offset;
- io_parms.length = len;
- rc = server->ops->sync_write(xid, &open_file->fid,
- &io_parms, &bytes_written, iov, 1);
- }
- if (rc || (bytes_written == 0)) {
- if (total_written)
- break;
- else {
- free_xid(xid);
- return rc;
- }
- } else {
- spin_lock(&d_inode(dentry)->i_lock);
- cifs_update_eof(cifsi, *offset, bytes_written);
- spin_unlock(&d_inode(dentry)->i_lock);
- *offset += bytes_written;
- }
- }
- cifs_stats_bytes_written(tcon, total_written);
- if (total_written > 0) {
- spin_lock(&d_inode(dentry)->i_lock);
- if (*offset > d_inode(dentry)->i_size)
- i_size_write(d_inode(dentry), *offset);
- spin_unlock(&d_inode(dentry)->i_lock);
- }
- mark_inode_dirty_sync(d_inode(dentry));
- free_xid(xid);
- return total_written;
- }
- struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
- bool fsuid_only)
- {
- struct cifsFileInfo *open_file = NULL;
- struct cifs_sb_info *cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
- struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
- /* only filter by fsuid on multiuser mounts */
- if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
- fsuid_only = false;
- spin_lock(&tcon->open_file_lock);
- /* we could simply get the first_list_entry since write-only entries
- are always at the end of the list but since the first entry might
- have a close pending, we go through the whole list */
- list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
- if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
- continue;
- if (OPEN_FMODE(open_file->f_flags) & FMODE_READ) {
- if (!open_file->invalidHandle) {
- /* found a good file */
- /* lock it so it will not be closed on us */
- cifsFileInfo_get(open_file);
- spin_unlock(&tcon->open_file_lock);
- return open_file;
- } /* else might as well continue, and look for
- another, or simply have the caller reopen it
- again rather than trying to fix this handle */
- } else /* write only file */
- break; /* write only files are last so must be done */
- }
- spin_unlock(&tcon->open_file_lock);
- return NULL;
- }
- struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode,
- bool fsuid_only)
- {
- struct cifsFileInfo *open_file, *inv_file = NULL;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- bool any_available = false;
- int rc;
- unsigned int refind = 0;
- /* Having a null inode here (because mapping->host was set to zero by
- the VFS or MM) should not happen but we had reports of on oops (due to
- it being zero) during stress testcases so we need to check for it */
- if (cifs_inode == NULL) {
- cifs_dbg(VFS, "Null inode passed to cifs_writeable_file\n");
- dump_stack();
- return NULL;
- }
- cifs_sb = CIFS_SB(cifs_inode->vfs_inode.i_sb);
- tcon = cifs_sb_master_tcon(cifs_sb);
- /* only filter by fsuid on multiuser mounts */
- if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
- fsuid_only = false;
- spin_lock(&tcon->open_file_lock);
- refind_writable:
- if (refind > MAX_REOPEN_ATT) {
- spin_unlock(&tcon->open_file_lock);
- return NULL;
- }
- list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
- if (!any_available && open_file->pid != current->tgid)
- continue;
- if (fsuid_only && !uid_eq(open_file->uid, current_fsuid()))
- continue;
- if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
- if (!open_file->invalidHandle) {
- /* found a good writable file */
- cifsFileInfo_get(open_file);
- spin_unlock(&tcon->open_file_lock);
- return open_file;
- } else {
- if (!inv_file)
- inv_file = open_file;
- }
- }
- }
- /* couldn't find useable FH with same pid, try any available */
- if (!any_available) {
- any_available = true;
- goto refind_writable;
- }
- if (inv_file) {
- any_available = false;
- cifsFileInfo_get(inv_file);
- }
- spin_unlock(&tcon->open_file_lock);
- if (inv_file) {
- rc = cifs_reopen_file(inv_file, false);
- if (!rc)
- return inv_file;
- else {
- spin_lock(&tcon->open_file_lock);
- list_move_tail(&inv_file->flist,
- &cifs_inode->openFileList);
- spin_unlock(&tcon->open_file_lock);
- cifsFileInfo_put(inv_file);
- ++refind;
- inv_file = NULL;
- spin_lock(&tcon->open_file_lock);
- goto refind_writable;
- }
- }
- return NULL;
- }
- static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
- {
- struct address_space *mapping = page->mapping;
- loff_t offset = (loff_t)page->index << PAGE_SHIFT;
- char *write_data;
- int rc = -EFAULT;
- int bytes_written = 0;
- struct inode *inode;
- struct cifsFileInfo *open_file;
- if (!mapping || !mapping->host)
- return -EFAULT;
- inode = page->mapping->host;
- offset += (loff_t)from;
- write_data = kmap(page);
- write_data += from;
- if ((to > PAGE_SIZE) || (from > to)) {
- kunmap(page);
- return -EIO;
- }
- /* racing with truncate? */
- if (offset > mapping->host->i_size) {
- kunmap(page);
- return 0; /* don't care */
- }
- /* check to make sure that we are not extending the file */
- if (mapping->host->i_size - offset < (loff_t)to)
- to = (unsigned)(mapping->host->i_size - offset);
- open_file = find_writable_file(CIFS_I(mapping->host), false);
- if (open_file) {
- bytes_written = cifs_write(open_file, open_file->pid,
- write_data, to - from, &offset);
- cifsFileInfo_put(open_file);
- /* Does mm or vfs already set times? */
- inode->i_atime = inode->i_mtime = current_time(inode);
- if ((bytes_written > 0) && (offset))
- rc = 0;
- else if (bytes_written < 0)
- rc = bytes_written;
- } else {
- cifs_dbg(FYI, "No writeable filehandles for inode\n");
- rc = -EIO;
- }
- kunmap(page);
- return rc;
- }
- static struct cifs_writedata *
- wdata_alloc_and_fillpages(pgoff_t tofind, struct address_space *mapping,
- pgoff_t end, pgoff_t *index,
- unsigned int *found_pages)
- {
- unsigned int nr_pages;
- struct page **pages;
- struct cifs_writedata *wdata;
- wdata = cifs_writedata_alloc((unsigned int)tofind,
- cifs_writev_complete);
- if (!wdata)
- return NULL;
- /*
- * find_get_pages_tag seems to return a max of 256 on each
- * iteration, so we must call it several times in order to
- * fill the array or the wsize is effectively limited to
- * 256 * PAGE_SIZE.
- */
- *found_pages = 0;
- pages = wdata->pages;
- do {
- nr_pages = find_get_pages_tag(mapping, index,
- PAGECACHE_TAG_DIRTY, tofind,
- pages);
- *found_pages += nr_pages;
- tofind -= nr_pages;
- pages += nr_pages;
- } while (nr_pages && tofind && *index <= end);
- return wdata;
- }
- static unsigned int
- wdata_prepare_pages(struct cifs_writedata *wdata, unsigned int found_pages,
- struct address_space *mapping,
- struct writeback_control *wbc,
- pgoff_t end, pgoff_t *index, pgoff_t *next, bool *done)
- {
- unsigned int nr_pages = 0, i;
- struct page *page;
- for (i = 0; i < found_pages; i++) {
- page = wdata->pages[i];
- /*
- * At this point we hold neither mapping->tree_lock nor
- * lock on the page itself: the page may be truncated or
- * invalidated (changing page->mapping to NULL), or even
- * swizzled back from swapper_space to tmpfs file
- * mapping
- */
- if (nr_pages == 0)
- lock_page(page);
- else if (!trylock_page(page))
- break;
- if (unlikely(page->mapping != mapping)) {
- unlock_page(page);
- break;
- }
- if (!wbc->range_cyclic && page->index > end) {
- *done = true;
- unlock_page(page);
- break;
- }
- if (*next && (page->index != *next)) {
- /* Not next consecutive page */
- unlock_page(page);
- break;
- }
- if (wbc->sync_mode != WB_SYNC_NONE)
- wait_on_page_writeback(page);
- if (PageWriteback(page) ||
- !clear_page_dirty_for_io(page)) {
- unlock_page(page);
- break;
- }
- /*
- * This actually clears the dirty bit in the radix tree.
- * See cifs_writepage() for more commentary.
- */
- set_page_writeback(page);
- if (page_offset(page) >= i_size_read(mapping->host)) {
- *done = true;
- unlock_page(page);
- end_page_writeback(page);
- break;
- }
- wdata->pages[i] = page;
- *next = page->index + 1;
- ++nr_pages;
- }
- /* reset index to refind any pages skipped */
- if (nr_pages == 0)
- *index = wdata->pages[0]->index + 1;
- /* put any pages we aren't going to use */
- for (i = nr_pages; i < found_pages; i++) {
- put_page(wdata->pages[i]);
- wdata->pages[i] = NULL;
- }
- return nr_pages;
- }
- static int
- wdata_send_pages(struct cifs_writedata *wdata, unsigned int nr_pages,
- struct address_space *mapping, struct writeback_control *wbc)
- {
- int rc = 0;
- struct TCP_Server_Info *server;
- unsigned int i;
- wdata->sync_mode = wbc->sync_mode;
- wdata->nr_pages = nr_pages;
- wdata->offset = page_offset(wdata->pages[0]);
- wdata->pagesz = PAGE_SIZE;
- wdata->tailsz = min(i_size_read(mapping->host) -
- page_offset(wdata->pages[nr_pages - 1]),
- (loff_t)PAGE_SIZE);
- wdata->bytes = ((nr_pages - 1) * PAGE_SIZE) + wdata->tailsz;
- if (wdata->cfile != NULL)
- cifsFileInfo_put(wdata->cfile);
- wdata->cfile = find_writable_file(CIFS_I(mapping->host), false);
- if (!wdata->cfile) {
- cifs_dbg(VFS, "No writable handles for inode\n");
- rc = -EBADF;
- } else {
- wdata->pid = wdata->cfile->pid;
- server = tlink_tcon(wdata->cfile->tlink)->ses->server;
- rc = server->ops->async_writev(wdata, cifs_writedata_release);
- }
- for (i = 0; i < nr_pages; ++i)
- unlock_page(wdata->pages[i]);
- return rc;
- }
- static int cifs_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
- {
- struct cifs_sb_info *cifs_sb = CIFS_SB(mapping->host->i_sb);
- struct TCP_Server_Info *server;
- bool done = false, scanned = false, range_whole = false;
- pgoff_t end, index;
- struct cifs_writedata *wdata;
- int rc = 0;
- /*
- * If wsize is smaller than the page cache size, default to writing
- * one page at a time via cifs_writepage
- */
- if (cifs_sb->wsize < PAGE_SIZE)
- return generic_writepages(mapping, wbc);
- if (wbc->range_cyclic) {
- index = mapping->writeback_index; /* Start from prev offset */
- end = -1;
- } else {
- index = wbc->range_start >> PAGE_SHIFT;
- end = wbc->range_end >> PAGE_SHIFT;
- if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
- range_whole = true;
- scanned = true;
- }
- server = cifs_sb_master_tcon(cifs_sb)->ses->server;
- retry:
- while (!done && index <= end) {
- unsigned int i, nr_pages, found_pages, wsize, credits;
- pgoff_t next = 0, tofind, saved_index = index;
- rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,
- &wsize, &credits);
- if (rc)
- break;
- tofind = min((wsize / PAGE_SIZE) - 1, end - index) + 1;
- wdata = wdata_alloc_and_fillpages(tofind, mapping, end, &index,
- &found_pages);
- if (!wdata) {
- rc = -ENOMEM;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- if (found_pages == 0) {
- kref_put(&wdata->refcount, cifs_writedata_release);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- nr_pages = wdata_prepare_pages(wdata, found_pages, mapping, wbc,
- end, &index, &next, &done);
- /* nothing to write? */
- if (nr_pages == 0) {
- kref_put(&wdata->refcount, cifs_writedata_release);
- add_credits_and_wake_if(server, credits, 0);
- continue;
- }
- wdata->credits = credits;
- rc = wdata_send_pages(wdata, nr_pages, mapping, wbc);
- /* send failure -- clean up the mess */
- if (rc != 0) {
- add_credits_and_wake_if(server, wdata->credits, 0);
- for (i = 0; i < nr_pages; ++i) {
- if (rc == -EAGAIN)
- redirty_page_for_writepage(wbc,
- wdata->pages[i]);
- else
- SetPageError(wdata->pages[i]);
- end_page_writeback(wdata->pages[i]);
- put_page(wdata->pages[i]);
- }
- if (rc != -EAGAIN)
- mapping_set_error(mapping, rc);
- }
- kref_put(&wdata->refcount, cifs_writedata_release);
- if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN) {
- index = saved_index;
- continue;
- }
- wbc->nr_to_write -= nr_pages;
- if (wbc->nr_to_write <= 0)
- done = true;
- index = next;
- }
- if (!scanned && !done) {
- /*
- * We hit the last page and there is more work to be done: wrap
- * back to the start of the file
- */
- scanned = true;
- index = 0;
- goto retry;
- }
- if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
- mapping->writeback_index = index;
- return rc;
- }
- static int
- cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
- {
- int rc;
- unsigned int xid;
- xid = get_xid();
- /* BB add check for wbc flags */
- get_page(page);
- if (!PageUptodate(page))
- cifs_dbg(FYI, "ppw - page not up to date\n");
- /*
- * Set the "writeback" flag, and clear "dirty" in the radix tree.
- *
- * A writepage() implementation always needs to do either this,
- * or re-dirty the page with "redirty_page_for_writepage()" in
- * the case of a failure.
- *
- * Just unlocking the page will cause the radix tree tag-bits
- * to fail to update with the state of the page correctly.
- */
- set_page_writeback(page);
- retry_write:
- rc = cifs_partialpagewrite(page, 0, PAGE_SIZE);
- if (rc == -EAGAIN && wbc->sync_mode == WB_SYNC_ALL)
- goto retry_write;
- else if (rc == -EAGAIN)
- redirty_page_for_writepage(wbc, page);
- else if (rc != 0)
- SetPageError(page);
- else
- SetPageUptodate(page);
- end_page_writeback(page);
- put_page(page);
- free_xid(xid);
- return rc;
- }
- static int cifs_writepage(struct page *page, struct writeback_control *wbc)
- {
- int rc = cifs_writepage_locked(page, wbc);
- unlock_page(page);
- return rc;
- }
- static int cifs_write_end(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
- {
- int rc;
- struct inode *inode = mapping->host;
- struct cifsFileInfo *cfile = file->private_data;
- struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
- __u32 pid;
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = cfile->pid;
- else
- pid = current->tgid;
- cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
- page, pos, copied);
- if (PageChecked(page)) {
- if (copied == len)
- SetPageUptodate(page);
- ClearPageChecked(page);
- } else if (!PageUptodate(page) && copied == PAGE_SIZE)
- SetPageUptodate(page);
- if (!PageUptodate(page)) {
- char *page_data;
- unsigned offset = pos & (PAGE_SIZE - 1);
- unsigned int xid;
- xid = get_xid();
- /* this is probably better than directly calling
- partialpage_write since in this function the file handle is
- known which we might as well leverage */
- /* BB check if anything else missing out of ppw
- such as updating last write time */
- page_data = kmap(page);
- rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
- /* if (rc < 0) should we set writebehind rc? */
- kunmap(page);
- free_xid(xid);
- } else {
- rc = copied;
- pos += copied;
- set_page_dirty(page);
- }
- if (rc > 0) {
- spin_lock(&inode->i_lock);
- if (pos > inode->i_size)
- i_size_write(inode, pos);
- spin_unlock(&inode->i_lock);
- }
- unlock_page(page);
- put_page(page);
- return rc;
- }
- int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
- int datasync)
- {
- unsigned int xid;
- int rc = 0;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- struct cifsFileInfo *smbfile = file->private_data;
- struct inode *inode = file_inode(file);
- struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
- rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
- if (rc)
- return rc;
- inode_lock(inode);
- xid = get_xid();
- cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
- file, datasync);
- if (!CIFS_CACHE_READ(CIFS_I(inode))) {
- rc = cifs_zap_mapping(inode);
- if (rc) {
- cifs_dbg(FYI, "rc: %d during invalidate phase\n", rc);
- rc = 0; /* don't care about it in fsync */
- }
- }
- tcon = tlink_tcon(smbfile->tlink);
- if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
- server = tcon->ses->server;
- if (server->ops->flush)
- rc = server->ops->flush(xid, tcon, &smbfile->fid);
- else
- rc = -ENOSYS;
- }
- free_xid(xid);
- inode_unlock(inode);
- return rc;
- }
- int cifs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
- {
- unsigned int xid;
- int rc = 0;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- struct cifsFileInfo *smbfile = file->private_data;
- struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
- struct inode *inode = file->f_mapping->host;
- rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
- if (rc)
- return rc;
- inode_lock(inode);
- xid = get_xid();
- cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
- file, datasync);
- tcon = tlink_tcon(smbfile->tlink);
- if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
- server = tcon->ses->server;
- if (server->ops->flush)
- rc = server->ops->flush(xid, tcon, &smbfile->fid);
- else
- rc = -ENOSYS;
- }
- free_xid(xid);
- inode_unlock(inode);
- return rc;
- }
- /*
- * As file closes, flush all cached write data for this inode checking
- * for write behind errors.
- */
- int cifs_flush(struct file *file, fl_owner_t id)
- {
- struct inode *inode = file_inode(file);
- int rc = 0;
- if (file->f_mode & FMODE_WRITE)
- rc = filemap_write_and_wait(inode->i_mapping);
- cifs_dbg(FYI, "Flush inode %p file %p rc %d\n", inode, file, rc);
- return rc;
- }
- static int
- cifs_write_allocate_pages(struct page **pages, unsigned long num_pages)
- {
- int rc = 0;
- unsigned long i;
- for (i = 0; i < num_pages; i++) {
- pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
- if (!pages[i]) {
- /*
- * save number of pages we have already allocated and
- * return with ENOMEM error
- */
- num_pages = i;
- rc = -ENOMEM;
- break;
- }
- }
- if (rc) {
- for (i = 0; i < num_pages; i++)
- put_page(pages[i]);
- }
- return rc;
- }
- static inline
- size_t get_numpages(const size_t wsize, const size_t len, size_t *cur_len)
- {
- size_t num_pages;
- size_t clen;
- clen = min_t(const size_t, len, wsize);
- num_pages = DIV_ROUND_UP(clen, PAGE_SIZE);
- if (cur_len)
- *cur_len = clen;
- return num_pages;
- }
- static void
- cifs_uncached_writedata_release(struct kref *refcount)
- {
- int i;
- struct cifs_writedata *wdata = container_of(refcount,
- struct cifs_writedata, refcount);
- for (i = 0; i < wdata->nr_pages; i++)
- put_page(wdata->pages[i]);
- cifs_writedata_release(refcount);
- }
- static void
- cifs_uncached_writev_complete(struct work_struct *work)
- {
- struct cifs_writedata *wdata = container_of(work,
- struct cifs_writedata, work);
- struct inode *inode = d_inode(wdata->cfile->dentry);
- struct cifsInodeInfo *cifsi = CIFS_I(inode);
- spin_lock(&inode->i_lock);
- cifs_update_eof(cifsi, wdata->offset, wdata->bytes);
- if (cifsi->server_eof > inode->i_size)
- i_size_write(inode, cifsi->server_eof);
- spin_unlock(&inode->i_lock);
- complete(&wdata->done);
- kref_put(&wdata->refcount, cifs_uncached_writedata_release);
- }
- static int
- wdata_fill_from_iovec(struct cifs_writedata *wdata, struct iov_iter *from,
- size_t *len, unsigned long *num_pages)
- {
- size_t save_len, copied, bytes, cur_len = *len;
- unsigned long i, nr_pages = *num_pages;
- save_len = cur_len;
- for (i = 0; i < nr_pages; i++) {
- bytes = min_t(const size_t, cur_len, PAGE_SIZE);
- copied = copy_page_from_iter(wdata->pages[i], 0, bytes, from);
- cur_len -= copied;
- /*
- * If we didn't copy as much as we expected, then that
- * may mean we trod into an unmapped area. Stop copying
- * at that point. On the next pass through the big
- * loop, we'll likely end up getting a zero-length
- * write and bailing out of it.
- */
- if (copied < bytes)
- break;
- }
- cur_len = save_len - cur_len;
- *len = cur_len;
- /*
- * If we have no data to send, then that probably means that
- * the copy above failed altogether. That's most likely because
- * the address in the iovec was bogus. Return -EFAULT and let
- * the caller free anything we allocated and bail out.
- */
- if (!cur_len)
- return -EFAULT;
- /*
- * i + 1 now represents the number of pages we actually used in
- * the copy phase above.
- */
- *num_pages = i + 1;
- return 0;
- }
- static int
- cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
- struct cifsFileInfo *open_file,
- struct cifs_sb_info *cifs_sb, struct list_head *wdata_list)
- {
- int rc = 0;
- size_t cur_len;
- unsigned long nr_pages, num_pages, i;
- struct cifs_writedata *wdata;
- struct iov_iter saved_from = *from;
- loff_t saved_offset = offset;
- pid_t pid;
- struct TCP_Server_Info *server;
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = open_file->pid;
- else
- pid = current->tgid;
- server = tlink_tcon(open_file->tlink)->ses->server;
- do {
- unsigned int wsize, credits;
- rc = server->ops->wait_mtu_credits(server, cifs_sb->wsize,
- &wsize, &credits);
- if (rc)
- break;
- nr_pages = get_numpages(wsize, len, &cur_len);
- wdata = cifs_writedata_alloc(nr_pages,
- cifs_uncached_writev_complete);
- if (!wdata) {
- rc = -ENOMEM;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- rc = cifs_write_allocate_pages(wdata->pages, nr_pages);
- if (rc) {
- kfree(wdata);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- num_pages = nr_pages;
- rc = wdata_fill_from_iovec(wdata, from, &cur_len, &num_pages);
- if (rc) {
- for (i = 0; i < nr_pages; i++)
- put_page(wdata->pages[i]);
- kfree(wdata);
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- /*
- * Bring nr_pages down to the number of pages we actually used,
- * and free any pages that we didn't use.
- */
- for ( ; nr_pages > num_pages; nr_pages--)
- put_page(wdata->pages[nr_pages - 1]);
- wdata->sync_mode = WB_SYNC_ALL;
- wdata->nr_pages = nr_pages;
- wdata->offset = (__u64)offset;
- wdata->cfile = cifsFileInfo_get(open_file);
- wdata->pid = pid;
- wdata->bytes = cur_len;
- wdata->pagesz = PAGE_SIZE;
- wdata->tailsz = cur_len - ((nr_pages - 1) * PAGE_SIZE);
- wdata->credits = credits;
- if (!wdata->cfile->invalidHandle ||
- !(rc = cifs_reopen_file(wdata->cfile, false)))
- rc = server->ops->async_writev(wdata,
- cifs_uncached_writedata_release);
- if (rc) {
- add_credits_and_wake_if(server, wdata->credits, 0);
- kref_put(&wdata->refcount,
- cifs_uncached_writedata_release);
- if (rc == -EAGAIN) {
- *from = saved_from;
- iov_iter_advance(from, offset - saved_offset);
- continue;
- }
- break;
- }
- list_add_tail(&wdata->list, wdata_list);
- offset += cur_len;
- len -= cur_len;
- } while (len > 0);
- return rc;
- }
- ssize_t cifs_user_writev(struct kiocb *iocb, struct iov_iter *from)
- {
- struct file *file = iocb->ki_filp;
- ssize_t total_written = 0;
- struct cifsFileInfo *open_file;
- struct cifs_tcon *tcon;
- struct cifs_sb_info *cifs_sb;
- struct cifs_writedata *wdata, *tmp;
- struct list_head wdata_list;
- struct iov_iter saved_from = *from;
- int rc;
- /*
- * BB - optimize the way when signing is disabled. We can drop this
- * extra memory-to-memory copying and use iovec buffers for constructing
- * write request.
- */
- rc = generic_write_checks(iocb, from);
- if (rc <= 0)
- return rc;
- INIT_LIST_HEAD(&wdata_list);
- cifs_sb = CIFS_FILE_SB(file);
- open_file = file->private_data;
- tcon = tlink_tcon(open_file->tlink);
- if (!tcon->ses->server->ops->async_writev)
- return -ENOSYS;
- rc = cifs_write_from_iter(iocb->ki_pos, iov_iter_count(from), from,
- open_file, cifs_sb, &wdata_list);
- /*
- * If at least one write was successfully sent, then discard any rc
- * value from the later writes. If the other write succeeds, then
- * we'll end up returning whatever was written. If it fails, then
- * we'll get a new rc value from that.
- */
- if (!list_empty(&wdata_list))
- rc = 0;
- /*
- * Wait for and collect replies for any successful sends in order of
- * increasing offset. Once an error is hit or we get a fatal signal
- * while waiting, then return without waiting for any more replies.
- */
- restart_loop:
- list_for_each_entry_safe(wdata, tmp, &wdata_list, list) {
- if (!rc) {
- /* FIXME: freezable too? */
- rc = wait_for_completion_killable(&wdata->done);
- if (rc)
- rc = -EINTR;
- else if (wdata->result)
- rc = wdata->result;
- else
- total_written += wdata->bytes;
- /* resend call if it's a retryable error */
- if (rc == -EAGAIN) {
- struct list_head tmp_list;
- struct iov_iter tmp_from = saved_from;
- INIT_LIST_HEAD(&tmp_list);
- list_del_init(&wdata->list);
- iov_iter_advance(&tmp_from,
- wdata->offset - iocb->ki_pos);
- rc = cifs_write_from_iter(wdata->offset,
- wdata->bytes, &tmp_from,
- open_file, cifs_sb, &tmp_list);
- list_splice(&tmp_list, &wdata_list);
- kref_put(&wdata->refcount,
- cifs_uncached_writedata_release);
- goto restart_loop;
- }
- }
- list_del_init(&wdata->list);
- kref_put(&wdata->refcount, cifs_uncached_writedata_release);
- }
- if (unlikely(!total_written))
- return rc;
- iocb->ki_pos += total_written;
- set_bit(CIFS_INO_INVALID_MAPPING, &CIFS_I(file_inode(file))->flags);
- cifs_stats_bytes_written(tcon, total_written);
- return total_written;
- }
- static ssize_t
- cifs_writev(struct kiocb *iocb, struct iov_iter *from)
- {
- struct file *file = iocb->ki_filp;
- struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
- struct inode *inode = file->f_mapping->host;
- struct cifsInodeInfo *cinode = CIFS_I(inode);
- struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
- ssize_t rc;
- /*
- * We need to hold the sem to be sure nobody modifies lock list
- * with a brlock that prevents writing.
- */
- down_read(&cinode->lock_sem);
- inode_lock(inode);
- rc = generic_write_checks(iocb, from);
- if (rc <= 0)
- goto out;
- if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(from),
- server->vals->exclusive_lock_type, NULL,
- CIFS_WRITE_OP))
- rc = __generic_file_write_iter(iocb, from);
- else
- rc = -EACCES;
- out:
- inode_unlock(inode);
- if (rc > 0)
- rc = generic_write_sync(iocb, rc);
- up_read(&cinode->lock_sem);
- return rc;
- }
- ssize_t
- cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from)
- {
- struct inode *inode = file_inode(iocb->ki_filp);
- struct cifsInodeInfo *cinode = CIFS_I(inode);
- struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
- struct cifsFileInfo *cfile = (struct cifsFileInfo *)
- iocb->ki_filp->private_data;
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- ssize_t written;
- written = cifs_get_writer(cinode);
- if (written)
- return written;
- if (CIFS_CACHE_WRITE(cinode)) {
- if (cap_unix(tcon->ses) &&
- (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
- && ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
- written = generic_file_write_iter(iocb, from);
- goto out;
- }
- written = cifs_writev(iocb, from);
- goto out;
- }
- /*
- * For non-oplocked files in strict cache mode we need to write the data
- * to the server exactly from the pos to pos+len-1 rather than flush all
- * affected pages because it may cause a error with mandatory locks on
- * these pages but not on the region from pos to ppos+len-1.
- */
- written = cifs_user_writev(iocb, from);
- if (written > 0 && CIFS_CACHE_READ(cinode)) {
- /*
- * Windows 7 server can delay breaking level2 oplock if a write
- * request comes - break it on the client to prevent reading
- * an old data.
- */
- cifs_zap_mapping(inode);
- cifs_dbg(FYI, "Set no oplock for inode=%p after a write operation\n",
- inode);
- cinode->oplock = 0;
- }
- out:
- cifs_put_writer(cinode);
- return written;
- }
- static struct cifs_readdata *
- cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete)
- {
- struct cifs_readdata *rdata;
- rdata = kzalloc(sizeof(*rdata) + (sizeof(struct page *) * nr_pages),
- GFP_KERNEL);
- if (rdata != NULL) {
- kref_init(&rdata->refcount);
- INIT_LIST_HEAD(&rdata->list);
- init_completion(&rdata->done);
- INIT_WORK(&rdata->work, complete);
- }
- return rdata;
- }
- void
- cifs_readdata_release(struct kref *refcount)
- {
- struct cifs_readdata *rdata = container_of(refcount,
- struct cifs_readdata, refcount);
- if (rdata->cfile)
- cifsFileInfo_put(rdata->cfile);
- kfree(rdata);
- }
- static int
- cifs_read_allocate_pages(struct cifs_readdata *rdata, unsigned int nr_pages)
- {
- int rc = 0;
- struct page *page;
- unsigned int i;
- for (i = 0; i < nr_pages; i++) {
- page = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
- if (!page) {
- rc = -ENOMEM;
- break;
- }
- rdata->pages[i] = page;
- }
- if (rc) {
- for (i = 0; i < nr_pages; i++) {
- put_page(rdata->pages[i]);
- rdata->pages[i] = NULL;
- }
- }
- return rc;
- }
- static void
- cifs_uncached_readdata_release(struct kref *refcount)
- {
- struct cifs_readdata *rdata = container_of(refcount,
- struct cifs_readdata, refcount);
- unsigned int i;
- for (i = 0; i < rdata->nr_pages; i++) {
- put_page(rdata->pages[i]);
- rdata->pages[i] = NULL;
- }
- cifs_readdata_release(refcount);
- }
- /**
- * cifs_readdata_to_iov - copy data from pages in response to an iovec
- * @rdata: the readdata response with list of pages holding data
- * @iter: destination for our data
- *
- * This function copies data from a list of pages in a readdata response into
- * an array of iovecs. It will first calculate where the data should go
- * based on the info in the readdata and then copy the data into that spot.
- */
- static int
- cifs_readdata_to_iov(struct cifs_readdata *rdata, struct iov_iter *iter)
- {
- size_t remaining = rdata->got_bytes;
- unsigned int i;
- for (i = 0; i < rdata->nr_pages; i++) {
- struct page *page = rdata->pages[i];
- size_t copy = min_t(size_t, remaining, PAGE_SIZE);
- size_t written;
- if (unlikely(iter->type & ITER_PIPE)) {
- void *addr = kmap_atomic(page);
- written = copy_to_iter(addr, copy, iter);
- kunmap_atomic(addr);
- } else
- written = copy_page_to_iter(page, 0, copy, iter);
- remaining -= written;
- if (written < copy && iov_iter_count(iter) > 0)
- break;
- }
- return remaining ? -EFAULT : 0;
- }
- static void
- cifs_uncached_readv_complete(struct work_struct *work)
- {
- struct cifs_readdata *rdata = container_of(work,
- struct cifs_readdata, work);
- complete(&rdata->done);
- kref_put(&rdata->refcount, cifs_uncached_readdata_release);
- }
- static int
- cifs_uncached_read_into_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata, unsigned int len)
- {
- int result = 0;
- unsigned int i;
- unsigned int nr_pages = rdata->nr_pages;
- rdata->got_bytes = 0;
- rdata->tailsz = PAGE_SIZE;
- for (i = 0; i < nr_pages; i++) {
- struct page *page = rdata->pages[i];
- size_t n;
- if (len <= 0) {
- /* no need to hold page hostage */
- rdata->pages[i] = NULL;
- rdata->nr_pages--;
- put_page(page);
- continue;
- }
- n = len;
- if (len >= PAGE_SIZE) {
- /* enough data to fill the page */
- n = PAGE_SIZE;
- len -= n;
- } else {
- zero_user(page, len, PAGE_SIZE - len);
- rdata->tailsz = len;
- len = 0;
- }
- result = cifs_read_page_from_socket(server, page, n);
- if (result < 0)
- break;
- rdata->got_bytes += result;
- }
- return rdata->got_bytes > 0 && result != -ECONNABORTED ?
- rdata->got_bytes : result;
- }
- static int
- cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
- struct cifs_sb_info *cifs_sb, struct list_head *rdata_list)
- {
- struct cifs_readdata *rdata;
- unsigned int npages, rsize, credits;
- size_t cur_len;
- int rc;
- pid_t pid;
- struct TCP_Server_Info *server;
- server = tlink_tcon(open_file->tlink)->ses->server;
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = open_file->pid;
- else
- pid = current->tgid;
- do {
- rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
- &rsize, &credits);
- if (rc)
- break;
- cur_len = min_t(const size_t, len, rsize);
- npages = DIV_ROUND_UP(cur_len, PAGE_SIZE);
- /* allocate a readdata struct */
- rdata = cifs_readdata_alloc(npages,
- cifs_uncached_readv_complete);
- if (!rdata) {
- add_credits_and_wake_if(server, credits, 0);
- rc = -ENOMEM;
- break;
- }
- rc = cifs_read_allocate_pages(rdata, npages);
- if (rc)
- goto error;
- rdata->cfile = cifsFileInfo_get(open_file);
- rdata->nr_pages = npages;
- rdata->offset = offset;
- rdata->bytes = cur_len;
- rdata->pid = pid;
- rdata->pagesz = PAGE_SIZE;
- rdata->read_into_pages = cifs_uncached_read_into_pages;
- rdata->credits = credits;
- if (!rdata->cfile->invalidHandle ||
- !(rc = cifs_reopen_file(rdata->cfile, true)))
- rc = server->ops->async_readv(rdata);
- error:
- if (rc) {
- add_credits_and_wake_if(server, rdata->credits, 0);
- kref_put(&rdata->refcount,
- cifs_uncached_readdata_release);
- if (rc == -EAGAIN)
- continue;
- break;
- }
- list_add_tail(&rdata->list, rdata_list);
- offset += cur_len;
- len -= cur_len;
- } while (len > 0);
- return rc;
- }
- ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to)
- {
- struct file *file = iocb->ki_filp;
- ssize_t rc;
- size_t len;
- ssize_t total_read = 0;
- loff_t offset = iocb->ki_pos;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- struct cifsFileInfo *open_file;
- struct cifs_readdata *rdata, *tmp;
- struct list_head rdata_list;
- len = iov_iter_count(to);
- if (!len)
- return 0;
- INIT_LIST_HEAD(&rdata_list);
- cifs_sb = CIFS_FILE_SB(file);
- open_file = file->private_data;
- tcon = tlink_tcon(open_file->tlink);
- if (!tcon->ses->server->ops->async_readv)
- return -ENOSYS;
- if ((file->f_flags & O_ACCMODE) == O_WRONLY)
- cifs_dbg(FYI, "attempting read on write only file instance\n");
- rc = cifs_send_async_read(offset, len, open_file, cifs_sb, &rdata_list);
- /* if at least one read request send succeeded, then reset rc */
- if (!list_empty(&rdata_list))
- rc = 0;
- len = iov_iter_count(to);
- /* the loop below should proceed in the order of increasing offsets */
- again:
- list_for_each_entry_safe(rdata, tmp, &rdata_list, list) {
- if (!rc) {
- /* FIXME: freezable sleep too? */
- rc = wait_for_completion_killable(&rdata->done);
- if (rc)
- rc = -EINTR;
- else if (rdata->result == -EAGAIN) {
- /* resend call if it's a retryable error */
- struct list_head tmp_list;
- unsigned int got_bytes = rdata->got_bytes;
- list_del_init(&rdata->list);
- INIT_LIST_HEAD(&tmp_list);
- /*
- * Got a part of data and then reconnect has
- * happened -- fill the buffer and continue
- * reading.
- */
- if (got_bytes && got_bytes < rdata->bytes) {
- rc = cifs_readdata_to_iov(rdata, to);
- if (rc) {
- kref_put(&rdata->refcount,
- cifs_uncached_readdata_release);
- continue;
- }
- }
- rc = cifs_send_async_read(
- rdata->offset + got_bytes,
- rdata->bytes - got_bytes,
- rdata->cfile, cifs_sb,
- &tmp_list);
- list_splice(&tmp_list, &rdata_list);
- kref_put(&rdata->refcount,
- cifs_uncached_readdata_release);
- goto again;
- } else if (rdata->result)
- rc = rdata->result;
- else
- rc = cifs_readdata_to_iov(rdata, to);
- /* if there was a short read -- discard anything left */
- if (rdata->got_bytes && rdata->got_bytes < rdata->bytes)
- rc = -ENODATA;
- }
- list_del_init(&rdata->list);
- kref_put(&rdata->refcount, cifs_uncached_readdata_release);
- }
- total_read = len - iov_iter_count(to);
- cifs_stats_bytes_read(tcon, total_read);
- /* mask nodata case */
- if (rc == -ENODATA)
- rc = 0;
- if (total_read) {
- iocb->ki_pos += total_read;
- return total_read;
- }
- return rc;
- }
- ssize_t
- cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
- {
- struct inode *inode = file_inode(iocb->ki_filp);
- struct cifsInodeInfo *cinode = CIFS_I(inode);
- struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
- struct cifsFileInfo *cfile = (struct cifsFileInfo *)
- iocb->ki_filp->private_data;
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- int rc = -EACCES;
- /*
- * In strict cache mode we need to read from the server all the time
- * if we don't have level II oplock because the server can delay mtime
- * change - so we can't make a decision about inode invalidating.
- * And we can also fail with pagereading if there are mandatory locks
- * on pages affected by this read but not on the region from pos to
- * pos+len-1.
- */
- if (!CIFS_CACHE_READ(cinode))
- return cifs_user_readv(iocb, to);
- if (cap_unix(tcon->ses) &&
- (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
- ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
- return generic_file_read_iter(iocb, to);
- /*
- * We need to hold the sem to be sure nobody modifies lock list
- * with a brlock that prevents reading.
- */
- down_read(&cinode->lock_sem);
- if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(to),
- tcon->ses->server->vals->shared_lock_type,
- NULL, CIFS_READ_OP))
- rc = generic_file_read_iter(iocb, to);
- up_read(&cinode->lock_sem);
- return rc;
- }
- static ssize_t
- cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
- {
- int rc = -EACCES;
- unsigned int bytes_read = 0;
- unsigned int total_read;
- unsigned int current_read_size;
- unsigned int rsize;
- struct cifs_sb_info *cifs_sb;
- struct cifs_tcon *tcon;
- struct TCP_Server_Info *server;
- unsigned int xid;
- char *cur_offset;
- struct cifsFileInfo *open_file;
- struct cifs_io_parms io_parms;
- int buf_type = CIFS_NO_BUFFER;
- __u32 pid;
- xid = get_xid();
- cifs_sb = CIFS_FILE_SB(file);
- /* FIXME: set up handlers for larger reads and/or convert to async */
- rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
- if (file->private_data == NULL) {
- rc = -EBADF;
- free_xid(xid);
- return rc;
- }
- open_file = file->private_data;
- tcon = tlink_tcon(open_file->tlink);
- server = tcon->ses->server;
- if (!server->ops->sync_read) {
- free_xid(xid);
- return -ENOSYS;
- }
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = open_file->pid;
- else
- pid = current->tgid;
- if ((file->f_flags & O_ACCMODE) == O_WRONLY)
- cifs_dbg(FYI, "attempting read on write only file instance\n");
- for (total_read = 0, cur_offset = read_data; read_size > total_read;
- total_read += bytes_read, cur_offset += bytes_read) {
- do {
- current_read_size = min_t(uint, read_size - total_read,
- rsize);
- /*
- * For windows me and 9x we do not want to request more
- * than it negotiated since it will refuse the read
- * then.
- */
- if ((tcon->ses) && !(tcon->ses->capabilities &
- tcon->ses->server->vals->cap_large_files)) {
- current_read_size = min_t(uint,
- current_read_size, CIFSMaxBufSize);
- }
- if (open_file->invalidHandle) {
- rc = cifs_reopen_file(open_file, true);
- if (rc != 0)
- break;
- }
- io_parms.pid = pid;
- io_parms.tcon = tcon;
- io_parms.offset = *offset;
- io_parms.length = current_read_size;
- rc = server->ops->sync_read(xid, &open_file->fid, &io_parms,
- &bytes_read, &cur_offset,
- &buf_type);
- } while (rc == -EAGAIN);
- if (rc || (bytes_read == 0)) {
- if (total_read) {
- break;
- } else {
- free_xid(xid);
- return rc;
- }
- } else {
- cifs_stats_bytes_read(tcon, total_read);
- *offset += bytes_read;
- }
- }
- free_xid(xid);
- return total_read;
- }
- /*
- * If the page is mmap'ed into a process' page tables, then we need to make
- * sure that it doesn't change while being written back.
- */
- static int
- cifs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
- {
- struct page *page = vmf->page;
- lock_page(page);
- return VM_FAULT_LOCKED;
- }
- static const struct vm_operations_struct cifs_file_vm_ops = {
- .fault = filemap_fault,
- .map_pages = filemap_map_pages,
- .page_mkwrite = cifs_page_mkwrite,
- };
- int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
- {
- int xid, rc = 0;
- struct inode *inode = file_inode(file);
- xid = get_xid();
- if (!CIFS_CACHE_READ(CIFS_I(inode)))
- rc = cifs_zap_mapping(inode);
- if (!rc)
- rc = generic_file_mmap(file, vma);
- if (!rc)
- vma->vm_ops = &cifs_file_vm_ops;
- free_xid(xid);
- return rc;
- }
- int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
- {
- int rc, xid;
- xid = get_xid();
- rc = cifs_revalidate_file(file);
- if (rc)
- cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
- rc);
- if (!rc)
- rc = generic_file_mmap(file, vma);
- if (!rc)
- vma->vm_ops = &cifs_file_vm_ops;
- free_xid(xid);
- return rc;
- }
- static void
- cifs_readv_complete(struct work_struct *work)
- {
- unsigned int i, got_bytes;
- struct cifs_readdata *rdata = container_of(work,
- struct cifs_readdata, work);
- got_bytes = rdata->got_bytes;
- for (i = 0; i < rdata->nr_pages; i++) {
- struct page *page = rdata->pages[i];
- lru_cache_add_file(page);
- if (rdata->result == 0 ||
- (rdata->result == -EAGAIN && got_bytes)) {
- flush_dcache_page(page);
- SetPageUptodate(page);
- }
- unlock_page(page);
- if (rdata->result == 0 ||
- (rdata->result == -EAGAIN && got_bytes))
- cifs_readpage_to_fscache(rdata->mapping->host, page);
- got_bytes -= min_t(unsigned int, PAGE_SIZE, got_bytes);
- put_page(page);
- rdata->pages[i] = NULL;
- }
- kref_put(&rdata->refcount, cifs_readdata_release);
- }
- static int
- cifs_readpages_read_into_pages(struct TCP_Server_Info *server,
- struct cifs_readdata *rdata, unsigned int len)
- {
- int result = 0;
- unsigned int i;
- u64 eof;
- pgoff_t eof_index;
- unsigned int nr_pages = rdata->nr_pages;
- /* determine the eof that the server (probably) has */
- eof = CIFS_I(rdata->mapping->host)->server_eof;
- eof_index = eof ? (eof - 1) >> PAGE_SHIFT : 0;
- cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index);
- rdata->got_bytes = 0;
- rdata->tailsz = PAGE_SIZE;
- for (i = 0; i < nr_pages; i++) {
- struct page *page = rdata->pages[i];
- size_t n = PAGE_SIZE;
- if (len >= PAGE_SIZE) {
- len -= PAGE_SIZE;
- } else if (len > 0) {
- /* enough for partial page, fill and zero the rest */
- zero_user(page, len, PAGE_SIZE - len);
- n = rdata->tailsz = len;
- len = 0;
- } else if (page->index > eof_index) {
- /*
- * The VFS will not try to do readahead past the
- * i_size, but it's possible that we have outstanding
- * writes with gaps in the middle and the i_size hasn't
- * caught up yet. Populate those with zeroed out pages
- * to prevent the VFS from repeatedly attempting to
- * fill them until the writes are flushed.
- */
- zero_user(page, 0, PAGE_SIZE);
- lru_cache_add_file(page);
- flush_dcache_page(page);
- SetPageUptodate(page);
- unlock_page(page);
- put_page(page);
- rdata->pages[i] = NULL;
- rdata->nr_pages--;
- continue;
- } else {
- /* no need to hold page hostage */
- lru_cache_add_file(page);
- unlock_page(page);
- put_page(page);
- rdata->pages[i] = NULL;
- rdata->nr_pages--;
- continue;
- }
- result = cifs_read_page_from_socket(server, page, n);
- if (result < 0)
- break;
- rdata->got_bytes += result;
- }
- return rdata->got_bytes > 0 && result != -ECONNABORTED ?
- rdata->got_bytes : result;
- }
- static int
- readpages_get_pages(struct address_space *mapping, struct list_head *page_list,
- unsigned int rsize, struct list_head *tmplist,
- unsigned int *nr_pages, loff_t *offset, unsigned int *bytes)
- {
- struct page *page, *tpage;
- unsigned int expected_index;
- int rc;
- gfp_t gfp = readahead_gfp_mask(mapping);
- INIT_LIST_HEAD(tmplist);
- page = list_entry(page_list->prev, struct page, lru);
- /*
- * Lock the page and put it in the cache. Since no one else
- * should have access to this page, we're safe to simply set
- * PG_locked without checking it first.
- */
- __SetPageLocked(page);
- rc = add_to_page_cache_locked(page, mapping,
- page->index, gfp);
- /* give up if we can't stick it in the cache */
- if (rc) {
- __ClearPageLocked(page);
- return rc;
- }
- /* move first page to the tmplist */
- *offset = (loff_t)page->index << PAGE_SHIFT;
- *bytes = PAGE_SIZE;
- *nr_pages = 1;
- list_move_tail(&page->lru, tmplist);
- /* now try and add more pages onto the request */
- expected_index = page->index + 1;
- list_for_each_entry_safe_reverse(page, tpage, page_list, lru) {
- /* discontinuity ? */
- if (page->index != expected_index)
- break;
- /* would this page push the read over the rsize? */
- if (*bytes + PAGE_SIZE > rsize)
- break;
- __SetPageLocked(page);
- if (add_to_page_cache_locked(page, mapping, page->index, gfp)) {
- __ClearPageLocked(page);
- break;
- }
- list_move_tail(&page->lru, tmplist);
- (*bytes) += PAGE_SIZE;
- expected_index++;
- (*nr_pages)++;
- }
- return rc;
- }
- static int cifs_readpages(struct file *file, struct address_space *mapping,
- struct list_head *page_list, unsigned num_pages)
- {
- int rc;
- struct list_head tmplist;
- struct cifsFileInfo *open_file = file->private_data;
- struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
- struct TCP_Server_Info *server;
- pid_t pid;
- /*
- * Reads as many pages as possible from fscache. Returns -ENOBUFS
- * immediately if the cookie is negative
- *
- * After this point, every page in the list might have PG_fscache set,
- * so we will need to clean that up off of every page we don't use.
- */
- rc = cifs_readpages_from_fscache(mapping->host, mapping, page_list,
- &num_pages);
- if (rc == 0)
- return rc;
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = open_file->pid;
- else
- pid = current->tgid;
- rc = 0;
- server = tlink_tcon(open_file->tlink)->ses->server;
- cifs_dbg(FYI, "%s: file=%p mapping=%p num_pages=%u\n",
- __func__, file, mapping, num_pages);
- /*
- * Start with the page at end of list and move it to private
- * list. Do the same with any following pages until we hit
- * the rsize limit, hit an index discontinuity, or run out of
- * pages. Issue the async read and then start the loop again
- * until the list is empty.
- *
- * Note that list order is important. The page_list is in
- * the order of declining indexes. When we put the pages in
- * the rdata->pages, then we want them in increasing order.
- */
- while (!list_empty(page_list)) {
- unsigned int i, nr_pages, bytes, rsize;
- loff_t offset;
- struct page *page, *tpage;
- struct cifs_readdata *rdata;
- unsigned credits;
- rc = server->ops->wait_mtu_credits(server, cifs_sb->rsize,
- &rsize, &credits);
- if (rc)
- break;
- /*
- * Give up immediately if rsize is too small to read an entire
- * page. The VFS will fall back to readpage. We should never
- * reach this point however since we set ra_pages to 0 when the
- * rsize is smaller than a cache page.
- */
- if (unlikely(rsize < PAGE_SIZE)) {
- add_credits_and_wake_if(server, credits, 0);
- return 0;
- }
- rc = readpages_get_pages(mapping, page_list, rsize, &tmplist,
- &nr_pages, &offset, &bytes);
- if (rc) {
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- rdata = cifs_readdata_alloc(nr_pages, cifs_readv_complete);
- if (!rdata) {
- /* best to give up if we're out of mem */
- list_for_each_entry_safe(page, tpage, &tmplist, lru) {
- list_del(&page->lru);
- lru_cache_add_file(page);
- unlock_page(page);
- put_page(page);
- }
- rc = -ENOMEM;
- add_credits_and_wake_if(server, credits, 0);
- break;
- }
- rdata->cfile = cifsFileInfo_get(open_file);
- rdata->mapping = mapping;
- rdata->offset = offset;
- rdata->bytes = bytes;
- rdata->pid = pid;
- rdata->pagesz = PAGE_SIZE;
- rdata->read_into_pages = cifs_readpages_read_into_pages;
- rdata->credits = credits;
- list_for_each_entry_safe(page, tpage, &tmplist, lru) {
- list_del(&page->lru);
- rdata->pages[rdata->nr_pages++] = page;
- }
- if (!rdata->cfile->invalidHandle ||
- !(rc = cifs_reopen_file(rdata->cfile, true)))
- rc = server->ops->async_readv(rdata);
- if (rc) {
- add_credits_and_wake_if(server, rdata->credits, 0);
- for (i = 0; i < rdata->nr_pages; i++) {
- page = rdata->pages[i];
- lru_cache_add_file(page);
- unlock_page(page);
- put_page(page);
- }
- /* Fallback to the readpage in error/reconnect cases */
- kref_put(&rdata->refcount, cifs_readdata_release);
- break;
- }
- kref_put(&rdata->refcount, cifs_readdata_release);
- }
- /* Any pages that have been shown to fscache but didn't get added to
- * the pagecache must be uncached before they get returned to the
- * allocator.
- */
- cifs_fscache_readpages_cancel(mapping->host, page_list);
- return rc;
- }
- /*
- * cifs_readpage_worker must be called with the page pinned
- */
- static int cifs_readpage_worker(struct file *file, struct page *page,
- loff_t *poffset)
- {
- char *read_data;
- int rc;
- /* Is the page cached? */
- rc = cifs_readpage_from_fscache(file_inode(file), page);
- if (rc == 0)
- goto read_complete;
- read_data = kmap(page);
- /* for reads over a certain size could initiate async read ahead */
- rc = cifs_read(file, read_data, PAGE_SIZE, poffset);
- if (rc < 0)
- goto io_error;
- else
- cifs_dbg(FYI, "Bytes read %d\n", rc);
- file_inode(file)->i_atime =
- current_time(file_inode(file));
- if (PAGE_SIZE > rc)
- memset(read_data + rc, 0, PAGE_SIZE - rc);
- flush_dcache_page(page);
- SetPageUptodate(page);
- /* send this page to the cache */
- cifs_readpage_to_fscache(file_inode(file), page);
- rc = 0;
- io_error:
- kunmap(page);
- unlock_page(page);
- read_complete:
- return rc;
- }
- static int cifs_readpage(struct file *file, struct page *page)
- {
- loff_t offset = (loff_t)page->index << PAGE_SHIFT;
- int rc = -EACCES;
- unsigned int xid;
- xid = get_xid();
- if (file->private_data == NULL) {
- rc = -EBADF;
- free_xid(xid);
- return rc;
- }
- cifs_dbg(FYI, "readpage %p at offset %d 0x%x\n",
- page, (int)offset, (int)offset);
- rc = cifs_readpage_worker(file, page, &offset);
- free_xid(xid);
- return rc;
- }
- static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
- {
- struct cifsFileInfo *open_file;
- struct cifs_tcon *tcon =
- cifs_sb_master_tcon(CIFS_SB(cifs_inode->vfs_inode.i_sb));
- spin_lock(&tcon->open_file_lock);
- list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
- if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
- spin_unlock(&tcon->open_file_lock);
- return 1;
- }
- }
- spin_unlock(&tcon->open_file_lock);
- return 0;
- }
- /* We do not want to update the file size from server for inodes
- open for write - to avoid races with writepage extending
- the file - in the future we could consider allowing
- refreshing the inode only on increases in the file size
- but this is tricky to do without racing with writebehind
- page caching in the current Linux kernel design */
- bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
- {
- if (!cifsInode)
- return true;
- if (is_inode_writable(cifsInode)) {
- /* This inode is open for write at least once */
- struct cifs_sb_info *cifs_sb;
- cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
- /* since no page cache to corrupt on directio
- we can change size safely */
- return true;
- }
- if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
- return true;
- return false;
- } else
- return true;
- }
- static int cifs_write_begin(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned flags,
- struct page **pagep, void **fsdata)
- {
- int oncethru = 0;
- pgoff_t index = pos >> PAGE_SHIFT;
- loff_t offset = pos & (PAGE_SIZE - 1);
- loff_t page_start = pos & PAGE_MASK;
- loff_t i_size;
- struct page *page;
- int rc = 0;
- cifs_dbg(FYI, "write_begin from %lld len %d\n", (long long)pos, len);
- start:
- page = grab_cache_page_write_begin(mapping, index, flags);
- if (!page) {
- rc = -ENOMEM;
- goto out;
- }
- if (PageUptodate(page))
- goto out;
- /*
- * If we write a full page it will be up to date, no need to read from
- * the server. If the write is short, we'll end up doing a sync write
- * instead.
- */
- if (len == PAGE_SIZE)
- goto out;
- /*
- * optimize away the read when we have an oplock, and we're not
- * expecting to use any of the data we'd be reading in. That
- * is, when the page lies beyond the EOF, or straddles the EOF
- * and the write will cover all of the existing data.
- */
- if (CIFS_CACHE_READ(CIFS_I(mapping->host))) {
- i_size = i_size_read(mapping->host);
- if (page_start >= i_size ||
- (offset == 0 && (pos + len) >= i_size)) {
- zero_user_segments(page, 0, offset,
- offset + len,
- PAGE_SIZE);
- /*
- * PageChecked means that the parts of the page
- * to which we're not writing are considered up
- * to date. Once the data is copied to the
- * page, it can be set uptodate.
- */
- SetPageChecked(page);
- goto out;
- }
- }
- if ((file->f_flags & O_ACCMODE) != O_WRONLY && !oncethru) {
- /*
- * might as well read a page, it is fast enough. If we get
- * an error, we don't need to return it. cifs_write_end will
- * do a sync write instead since PG_uptodate isn't set.
- */
- cifs_readpage_worker(file, page, &page_start);
- put_page(page);
- oncethru = 1;
- goto start;
- } else {
- /* we could try using another file handle if there is one -
- but how would we lock it to prevent close of that handle
- racing with this read? In any case
- this will be written out by write_end so is fine */
- }
- out:
- *pagep = page;
- return rc;
- }
- static int cifs_release_page(struct page *page, gfp_t gfp)
- {
- if (PagePrivate(page))
- return 0;
- return cifs_fscache_release_page(page, gfp);
- }
- static void cifs_invalidate_page(struct page *page, unsigned int offset,
- unsigned int length)
- {
- struct cifsInodeInfo *cifsi = CIFS_I(page->mapping->host);
- if (offset == 0 && length == PAGE_SIZE)
- cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
- }
- static int cifs_launder_page(struct page *page)
- {
- int rc = 0;
- loff_t range_start = page_offset(page);
- loff_t range_end = range_start + (loff_t)(PAGE_SIZE - 1);
- struct writeback_control wbc = {
- .sync_mode = WB_SYNC_ALL,
- .nr_to_write = 0,
- .range_start = range_start,
- .range_end = range_end,
- };
- cifs_dbg(FYI, "Launder page: %p\n", page);
- if (clear_page_dirty_for_io(page))
- rc = cifs_writepage_locked(page, &wbc);
- cifs_fscache_invalidate_page(page, page->mapping->host);
- return rc;
- }
- void cifs_oplock_break(struct work_struct *work)
- {
- struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
- oplock_break);
- struct inode *inode = d_inode(cfile->dentry);
- struct cifsInodeInfo *cinode = CIFS_I(inode);
- struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
- struct TCP_Server_Info *server = tcon->ses->server;
- int rc = 0;
- wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
- TASK_UNINTERRUPTIBLE);
- server->ops->downgrade_oplock(server, cinode,
- test_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2, &cinode->flags));
- if (!CIFS_CACHE_WRITE(cinode) && CIFS_CACHE_READ(cinode) &&
- cifs_has_mand_locks(cinode)) {
- cifs_dbg(FYI, "Reset oplock to None for inode=%p due to mand locks\n",
- inode);
- cinode->oplock = 0;
- }
- if (inode && S_ISREG(inode->i_mode)) {
- if (CIFS_CACHE_READ(cinode))
- break_lease(inode, O_RDONLY);
- else
- break_lease(inode, O_WRONLY);
- rc = filemap_fdatawrite(inode->i_mapping);
- if (!CIFS_CACHE_READ(cinode)) {
- rc = filemap_fdatawait(inode->i_mapping);
- mapping_set_error(inode->i_mapping, rc);
- cifs_zap_mapping(inode);
- }
- cifs_dbg(FYI, "Oplock flush inode %p rc %d\n", inode, rc);
- }
- rc = cifs_push_locks(cfile);
- if (rc)
- cifs_dbg(VFS, "Push locks rc = %d\n", rc);
- /*
- * releasing stale oplock after recent reconnect of smb session using
- * a now incorrect file handle is not a data integrity issue but do
- * not bother sending an oplock release if session to server still is
- * disconnected since oplock already released by the server
- */
- if (!cfile->oplock_break_cancelled) {
- rc = tcon->ses->server->ops->oplock_response(tcon, &cfile->fid,
- cinode);
- cifs_dbg(FYI, "Oplock release rc = %d\n", rc);
- }
- cifs_done_oplock_break(cinode);
- }
- /*
- * The presence of cifs_direct_io() in the address space ops vector
- * allowes open() O_DIRECT flags which would have failed otherwise.
- *
- * In the non-cached mode (mount with cache=none), we shunt off direct read and write requests
- * so this method should never be called.
- *
- * Direct IO is not yet supported in the cached mode.
- */
- static ssize_t
- cifs_direct_io(struct kiocb *iocb, struct iov_iter *iter)
- {
- /*
- * FIXME
- * Eventually need to support direct IO for non forcedirectio mounts
- */
- return -EINVAL;
- }
- const struct address_space_operations cifs_addr_ops = {
- .readpage = cifs_readpage,
- .readpages = cifs_readpages,
- .writepage = cifs_writepage,
- .writepages = cifs_writepages,
- .write_begin = cifs_write_begin,
- .write_end = cifs_write_end,
- .set_page_dirty = __set_page_dirty_nobuffers,
- .releasepage = cifs_release_page,
- .direct_IO = cifs_direct_io,
- .invalidatepage = cifs_invalidate_page,
- .launder_page = cifs_launder_page,
- };
- /*
- * cifs_readpages requires the server to support a buffer large enough to
- * contain the header plus one complete page of data. Otherwise, we need
- * to leave cifs_readpages out of the address space operations.
- */
- const struct address_space_operations cifs_addr_ops_smallbuf = {
- .readpage = cifs_readpage,
- .writepage = cifs_writepage,
- .writepages = cifs_writepages,
- .write_begin = cifs_write_begin,
- .write_end = cifs_write_end,
- .set_page_dirty = __set_page_dirty_nobuffers,
- .releasepage = cifs_release_page,
- .invalidatepage = cifs_invalidate_page,
- .launder_page = cifs_launder_page,
- };
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