| /* |
| * 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; |
| |
| 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->f_path.dentry; |
| 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); |
| |
| 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(&cifs_file_list_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(&cifs_file_list_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_list_lock); |
| cifsFileInfo_get_locked(cifs_file); |
| spin_unlock(&cifs_file_list_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 |
| * cifs_file_list_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(&cifs_file_list_lock); |
| if (--cifs_file->count > 0) { |
| spin_unlock(&cifs_file_list_lock); |
| return; |
| } |
| |
| 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(&cifs_file_list_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->f_path.dentry); |
| 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(&cinode->lock_sem); |
| 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. |
| */ |
| |
| 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; |
| } |
| |
| 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(&cifs_file_list_lock); |
| if (server->ops->dir_needs_close(cfile)) { |
| cfile->invalidHandle = true; |
| spin_unlock(&cifs_file_list_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(&cifs_file_list_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; |
| } |
| |
| 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 = flock->fl_pid; |
| 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, current->tgid, |
| 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, |
| current->tgid, 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 = posix_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); |
| |
| /* only filter by fsuid on multiuser mounts */ |
| if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER)) |
| fsuid_only = false; |
| |
| spin_lock(&cifs_file_list_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_locked(open_file); |
| spin_unlock(&cifs_file_list_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(&cifs_file_list_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; |
| 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); |
| |
| /* only filter by fsuid on multiuser mounts */ |
| if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER)) |
| fsuid_only = false; |
| |
| spin_lock(&cifs_file_list_lock); |
| refind_writable: |
| if (refind > MAX_REOPEN_ATT) { |
| spin_unlock(&cifs_file_list_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_locked(open_file); |
| spin_unlock(&cifs_file_list_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_locked(inv_file); |
| } |
| |
| spin_unlock(&cifs_file_list_lock); |
| |
| if (inv_file) { |
| rc = cifs_reopen_file(inv_file, false); |
| if (!rc) |
| return inv_file; |
| else { |
| spin_lock(&cifs_file_list_lock); |
| list_move_tail(&inv_file->flist, |
| &cifs_inode->openFileList); |
| spin_unlock(&cifs_file_list_lock); |
| cifsFileInfo_put(inv_file); |
| spin_lock(&cifs_file_list_lock); |
| ++refind; |
| inv_file = NULL; |
| 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_CACHE_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_CACHE_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_fs_time(inode->i_sb); |
| 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_CACHE_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++) { |
| page_cache_release(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_CACHE_SIZE; |
| wdata->tailsz = min(i_size_read(mapping->host) - |
| page_offset(wdata->pages[nr_pages - 1]), |
| (loff_t)PAGE_CACHE_SIZE); |
| wdata->bytes = ((nr_pages - 1) * PAGE_CACHE_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_CACHE_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_CACHE_SHIFT; |
| end = wbc->range_end >> PAGE_CACHE_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_CACHE_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]); |
| page_cache_release(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 */ |
| page_cache_get(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_CACHE_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); |
| page_cache_release(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_CACHE_SIZE) |
| SetPageUptodate(page); |
| |
| if (!PageUptodate(page)) { |
| char *page_data; |
| unsigned offset = pos & (PAGE_CACHE_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); |
| page_cache_release(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; |
| mutex_lock(&inode->i_mutex); |
| |
| 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); |
| mutex_unlock(&inode->i_mutex); |
| 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; |
| mutex_lock(&inode->i_mutex); |
| |
| 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); |
| mutex_unlock(&inode->i_mutex); |
| 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; |
| 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; |
| memcpy(&saved_from, from, sizeof(struct iov_iter)); |
| |
| 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 || |
| !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) { |
| memcpy(from, &saved_from, |
| sizeof(struct iov_iter)); |
| 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; |
| 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; |
| |
| memcpy(&saved_from, from, sizeof(struct iov_iter)); |
| |
| 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; |
| |
| INIT_LIST_HEAD(&tmp_list); |
| list_del_init(&wdata->list); |
| |
| memcpy(&tmp_from, &saved_from, |
| sizeof(struct iov_iter)); |
| 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); |
| mutex_lock(&inode->i_mutex); |
| |
| 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: |
| mutex_unlock(&inode->i_mutex); |
| |
| if (rc > 0) { |
| ssize_t err = generic_write_sync(file, iocb->ki_pos - rc, rc); |
| if (err < 0) |
| rc = err; |
| } |
| 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 = 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; |
| struct kvec iov; |
| |
| rdata->got_bytes = 0; |
| rdata->tailsz = PAGE_SIZE; |
| for (i = 0; i < nr_pages; i++) { |
| struct page *page = rdata->pages[i]; |
| |
| if (len >= PAGE_SIZE) { |
| /* enough data to fill the page */ |
| iov.iov_base = kmap(page); |
| iov.iov_len = PAGE_SIZE; |
| cifs_dbg(FYI, "%u: iov_base=%p iov_len=%zu\n", |
| i, iov.iov_base, iov.iov_len); |
| len -= PAGE_SIZE; |
| } else if (len > 0) { |
| /* enough for partial page, fill and zero the rest */ |
| iov.iov_base = kmap(page); |
| iov.iov_len = len; |
| cifs_dbg(FYI, "%u: iov_base=%p iov_len=%zu\n", |
| i, iov.iov_base, iov.iov_len); |
| memset(iov.iov_base + len, '\0', PAGE_SIZE - len); |
| rdata->tailsz = len; |
| len = 0; |
| } else { |
| /* no need to hold page hostage */ |
| rdata->pages[i] = NULL; |
| rdata->nr_pages--; |
| put_page(page); |
| continue; |
| } |
| |
| result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len); |
| kunmap(page); |
| 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 || |
| !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 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 rc, xid; |
| struct inode *inode = file_inode(file); |
| |
| xid = get_xid(); |
| |
| if (!CIFS_CACHE_READ(CIFS_I(inode))) { |
| rc = cifs_zap_mapping(inode); |
| if (rc) |
| return rc; |
| } |
| |
| rc = generic_file_mmap(file, vma); |
| if (rc == 0) |
| 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); |
| free_xid(xid); |
| return rc; |
| } |
| rc = generic_file_mmap(file, vma); |
| if (rc == 0) |
| 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_CACHE_SIZE, got_bytes); |
| |
| page_cache_release(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; |
| struct kvec iov; |
| |
| /* determine the eof that the server (probably) has */ |
| eof = CIFS_I(rdata->mapping->host)->server_eof; |
| eof_index = eof ? (eof - 1) >> PAGE_CACHE_SHIFT : 0; |
| cifs_dbg(FYI, "eof=%llu eof_index=%lu\n", eof, eof_index); |
| |
| rdata->got_bytes = 0; |
| rdata->tailsz = PAGE_CACHE_SIZE; |
| for (i = 0; i < nr_pages; i++) { |
| struct page *page = rdata->pages[i]; |
| |
| if (len >= PAGE_CACHE_SIZE) { |
| /* enough data to fill the page */ |
| iov.iov_base = kmap(page); |
| iov.iov_len = PAGE_CACHE_SIZE; |
| cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n", |
| i, page->index, iov.iov_base, iov.iov_len); |
| len -= PAGE_CACHE_SIZE; |
| } else if (len > 0) { |
| /* enough for partial page, fill and zero the rest */ |
| iov.iov_base = kmap(page); |
| iov.iov_len = len; |
| cifs_dbg(FYI, "%u: idx=%lu iov_base=%p iov_len=%zu\n", |
| i, page->index, iov.iov_base, iov.iov_len); |
| memset(iov.iov_base + len, |
| '\0', PAGE_CACHE_SIZE - len); |
| 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_CACHE_SIZE); |
| lru_cache_add_file(page); |
| flush_dcache_page(page); |
| SetPageUptodate(page); |
| unlock_page(page); |
| page_cache_release(page); |
| rdata->pages[i] = NULL; |
| rdata->nr_pages--; |
| continue; |
| } else { |
| /* no need to hold page hostage */ |
| lru_cache_add_file(page); |
| unlock_page(page); |
| page_cache_release(page); |
| rdata->pages[i] = NULL; |
| rdata->nr_pages--; |
| continue; |
| } |
| |
| result = cifs_readv_from_socket(server, &iov, 1, iov.iov_len); |
| kunmap(page); |
| 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; |
| |
| 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. |
| */ |
| __set_page_locked(page); |
| rc = add_to_page_cache_locked(page, mapping, |
| page->index, GFP_KERNEL); |
| |
| /* give up if we can't stick it in the cache */ |
| if (rc) { |
| __clear_page_locked(page); |
| return rc; |
| } |
| |
| /* move first page to the tmplist */ |
| *offset = (loff_t)page->index << PAGE_CACHE_SHIFT; |
| *bytes = PAGE_CACHE_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_CACHE_SIZE > rsize) |
| break; |
| |
| __set_page_locked(page); |
| if (add_to_page_cache_locked(page, mapping, page->index, |
| GFP_KERNEL)) { |
| __clear_page_locked(page); |
| break; |
| } |
| list_move_tail(&page->lru, tmplist); |
| (*bytes) += PAGE_CACHE_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_CACHE_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); |
| page_cache_release(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_CACHE_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 || |
| !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); |
| page_cache_release(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_CACHE_SIZE, poffset); |
| |
| if (rc < 0) |
| goto io_error; |
| else |
| cifs_dbg(FYI, "Bytes read %d\n", rc); |
| |
| file_inode(file)->i_atime = |
| current_fs_time(file_inode(file)->i_sb); |
| |
| if (PAGE_CACHE_SIZE > rc) |
| memset(read_data + rc, 0, PAGE_CACHE_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_CACHE_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; |
| |
| spin_lock(&cifs_file_list_lock); |
| list_for_each_entry(open_file, &cifs_inode->openFileList, flist) { |
| if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) { |
| spin_unlock(&cifs_file_list_lock); |
| return 1; |
| } |
| } |
| spin_unlock(&cifs_file_list_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_CACHE_SHIFT; |
| loff_t offset = pos & (PAGE_CACHE_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_CACHE_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_CACHE_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); |
| page_cache_release(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_CACHE_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_CACHE_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, loff_t pos) |
| { |
| /* |
| * 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, |
| }; |