From 03776f4516bc299b3145595bdd704d40d69adc02 Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Tue, 17 Aug 2010 11:26:00 +0400 Subject: [PATCH] CIFS: Simplify byte range locking code Split cifs_lock into several functions and let CIFSSMBLock get pid as an argument. Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/cifsglob.h | 1 + fs/cifs/cifsproto.h | 2 +- fs/cifs/cifssmb.c | 4 +- fs/cifs/file.c | 370 ++++++++++++++++++++++++++++------------------------ 4 files changed, 205 insertions(+), 172 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 3b83fe7..1f265ff 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -492,6 +492,7 @@ struct cifsLockInfo { struct list_head llist; /* pointer to next cifsLockInfo */ __u64 offset; __u64 length; + __u32 pid; __u8 type; }; diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 9ddb1ec..94834db 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -361,7 +361,7 @@ extern int CIFSGetSrvInodeNumber(const int xid, struct cifs_tcon *tcon, int remap_special_chars); extern int CIFSSMBLock(const int xid, struct cifs_tcon *tcon, - const __u16 netfid, const __u64 len, + const __u16 netfid, const __u32 netpid, const __u64 len, const __u64 offset, const __u32 numUnlock, const __u32 numLock, const __u8 lockType, const bool waitFlag, const __u8 oplock_level); diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 602326f..e33093f 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -1963,7 +1963,7 @@ CIFSSMBWrite2(const int xid, struct cifs_io_parms *io_parms, int CIFSSMBLock(const int xid, struct cifs_tcon *tcon, - const __u16 smb_file_id, const __u64 len, + const __u16 smb_file_id, const __u32 netpid, const __u64 len, const __u64 offset, const __u32 numUnlock, const __u32 numLock, const __u8 lockType, const bool waitFlag, const __u8 oplock_level) @@ -1999,7 +1999,7 @@ CIFSSMBLock(const int xid, struct cifs_tcon *tcon, pSMB->Fid = smb_file_id; /* netfid stays le */ if ((numLock != 0) || (numUnlock != 0)) { - pSMB->Locks[0].Pid = cpu_to_le16(current->tgid); + pSMB->Locks[0].Pid = cpu_to_le16(netpid); /* BB where to store pid high? */ pSMB->Locks[0].LengthLow = cpu_to_le32((u32)len); pSMB->Locks[0].LengthHigh = cpu_to_le32((u32)(len>>32)); diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 237192a..ab85699 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -639,8 +639,8 @@ int cifs_closedir(struct inode *inode, struct file *file) return rc; } -static int store_file_lock(struct cifsFileInfo *fid, __u64 len, - __u64 offset, __u8 lockType) +static int store_file_lock(struct cifsFileInfo *cfile, __u64 len, + __u64 offset, __u8 type, __u16 netfid) { struct cifsLockInfo *li = kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL); @@ -648,210 +648,241 @@ static int store_file_lock(struct cifsFileInfo *fid, __u64 len, return -ENOMEM; li->offset = offset; li->length = len; - li->type = lockType; - mutex_lock(&fid->lock_mutex); - list_add(&li->llist, &fid->llist); - mutex_unlock(&fid->lock_mutex); + li->type = type; + li->pid = current->tgid; + mutex_lock(&cfile->lock_mutex); + list_add_tail(&li->llist, &cfile->llist); + mutex_unlock(&cfile->lock_mutex); return 0; } -int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock) +static void +cifs_read_flock(struct file_lock *flock, __u8 *type, int *lock, int *unlock, + bool *wait_flag) { - int rc, xid; - __u32 numLock = 0; - __u32 numUnlock = 0; - __u64 length; - bool wait_flag = false; - struct cifs_sb_info *cifs_sb; - struct cifs_tcon *tcon; - __u16 netfid; - __u8 lockType = LOCKING_ANDX_LARGE_FILES; - bool posix_locking = 0; - - length = 1 + pfLock->fl_end - pfLock->fl_start; - rc = -EACCES; - xid = GetXid(); - - cFYI(1, "Lock parm: 0x%x flockflags: " - "0x%x flocktype: 0x%x start: %lld end: %lld", - cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start, - pfLock->fl_end); - - if (pfLock->fl_flags & FL_POSIX) + if (flock->fl_flags & FL_POSIX) cFYI(1, "Posix"); - if (pfLock->fl_flags & FL_FLOCK) + if (flock->fl_flags & FL_FLOCK) cFYI(1, "Flock"); - if (pfLock->fl_flags & FL_SLEEP) { + if (flock->fl_flags & FL_SLEEP) { cFYI(1, "Blocking lock"); - wait_flag = true; + *wait_flag = true; } - if (pfLock->fl_flags & FL_ACCESS) + if (flock->fl_flags & FL_ACCESS) cFYI(1, "Process suspended by mandatory locking - " - "not implemented yet"); - if (pfLock->fl_flags & FL_LEASE) + "not implemented yet"); + if (flock->fl_flags & FL_LEASE) cFYI(1, "Lease on file - not implemented yet"); - if (pfLock->fl_flags & + if (flock->fl_flags & (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE))) - cFYI(1, "Unknown lock flags 0x%x", pfLock->fl_flags); + cFYI(1, "Unknown lock flags 0x%x", flock->fl_flags); - if (pfLock->fl_type == F_WRLCK) { + *type = LOCKING_ANDX_LARGE_FILES; + if (flock->fl_type == F_WRLCK) { cFYI(1, "F_WRLCK "); - numLock = 1; - } else if (pfLock->fl_type == F_UNLCK) { + *lock = 1; + } else if (flock->fl_type == F_UNLCK) { cFYI(1, "F_UNLCK"); - numUnlock = 1; - /* Check if unlock includes more than - one lock range */ - } else if (pfLock->fl_type == F_RDLCK) { + *unlock = 1; + /* Check if unlock includes more than one lock range */ + } else if (flock->fl_type == F_RDLCK) { cFYI(1, "F_RDLCK"); - lockType |= LOCKING_ANDX_SHARED_LOCK; - numLock = 1; - } else if (pfLock->fl_type == F_EXLCK) { + *type |= LOCKING_ANDX_SHARED_LOCK; + *lock = 1; + } else if (flock->fl_type == F_EXLCK) { cFYI(1, "F_EXLCK"); - numLock = 1; - } else if (pfLock->fl_type == F_SHLCK) { + *lock = 1; + } else if (flock->fl_type == F_SHLCK) { cFYI(1, "F_SHLCK"); - lockType |= LOCKING_ANDX_SHARED_LOCK; - numLock = 1; + *type |= LOCKING_ANDX_SHARED_LOCK; + *lock = 1; } else cFYI(1, "Unknown type of lock"); +} - cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); - tcon = tlink_tcon(((struct cifsFileInfo *)file->private_data)->tlink); - netfid = ((struct cifsFileInfo *)file->private_data)->netfid; - - if ((tcon->ses->capabilities & CAP_UNIX) && - (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) && - ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) - posix_locking = 1; - /* 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)) { - if (posix_locking) { - int posix_lock_type; - if (lockType & LOCKING_ANDX_SHARED_LOCK) - posix_lock_type = CIFS_RDLCK; - else - posix_lock_type = CIFS_WRLCK; - rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */, - length, pfLock, posix_lock_type, - wait_flag); - FreeXid(xid); - return rc; - } - - /* BB we could chain these into one lock request BB */ - rc = CIFSSMBLock(xid, tcon, netfid, length, pfLock->fl_start, - 0, 1, lockType, 0 /* wait flag */, 0); - if (rc == 0) { - rc = CIFSSMBLock(xid, tcon, netfid, length, - pfLock->fl_start, 1 /* numUnlock */ , - 0 /* numLock */ , lockType, - 0 /* wait flag */, 0); - pfLock->fl_type = F_UNLCK; - if (rc != 0) - cERROR(1, "Error unlocking previously locked " - "range %d during test of lock", rc); - rc = 0; - - } else { - /* if rc == ERR_SHARING_VIOLATION ? */ - rc = 0; +static int +cifs_getlk(struct cifsFileInfo *cfile, struct file_lock *flock, __u8 type, + bool wait_flag, bool posix_lck, int xid) +{ + int rc = 0; + __u64 length = 1 + flock->fl_end - flock->fl_start; + __u16 netfid = cfile->netfid; + struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); - if (lockType & LOCKING_ANDX_SHARED_LOCK) { - pfLock->fl_type = F_WRLCK; - } else { - rc = CIFSSMBLock(xid, tcon, netfid, length, - pfLock->fl_start, 0, 1, - lockType | LOCKING_ANDX_SHARED_LOCK, - 0 /* wait flag */, 0); - if (rc == 0) { - rc = CIFSSMBLock(xid, tcon, netfid, - length, pfLock->fl_start, 1, 0, - lockType | - LOCKING_ANDX_SHARED_LOCK, - 0 /* wait flag */, 0); - pfLock->fl_type = F_RDLCK; - if (rc != 0) - cERROR(1, "Error unlocking " - "previously locked range %d " - "during test of lock", rc); - rc = 0; - } else { - pfLock->fl_type = F_WRLCK; - rc = 0; - } - } - } + if (posix_lck) { + int posix_lock_type; + if (type & LOCKING_ANDX_SHARED_LOCK) + posix_lock_type = CIFS_RDLCK; + else + posix_lock_type = CIFS_WRLCK; + rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */, + length, flock, posix_lock_type, + wait_flag); + return rc; + } - FreeXid(xid); + /* BB we could chain these into one lock request BB */ + rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, length, + flock->fl_start, 0, 1, type, 0, 0); + if (rc == 0) { + rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, + length, flock->fl_start, 1, 0, + type, 0, 0); + flock->fl_type = F_UNLCK; + if (rc != 0) + cERROR(1, "Error unlocking previously locked " + "range %d during test of lock", rc); + rc = 0; return rc; } - if (!numLock && !numUnlock) { - /* if no lock or unlock then nothing - to do since we do not know what it is */ - FreeXid(xid); - return -EOPNOTSUPP; + if (type & LOCKING_ANDX_SHARED_LOCK) { + flock->fl_type = F_WRLCK; + rc = 0; + return rc; } - if (posix_locking) { + rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, length, + flock->fl_start, 0, 1, + type | LOCKING_ANDX_SHARED_LOCK, 0, 0); + if (rc == 0) { + rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, + length, flock->fl_start, 1, 0, + type | LOCKING_ANDX_SHARED_LOCK, + 0, 0); + flock->fl_type = F_RDLCK; + if (rc != 0) + cERROR(1, "Error unlocking previously locked " + "range %d during test of lock", rc); + } else + flock->fl_type = F_WRLCK; + + rc = 0; + return rc; +} + +static int +cifs_setlk(struct file *file, struct file_lock *flock, __u8 type, + bool wait_flag, bool posix_lck, int lock, int unlock, 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); + __u16 netfid = cfile->netfid; + + if (posix_lck) { int posix_lock_type; - if (lockType & LOCKING_ANDX_SHARED_LOCK) + if (type & LOCKING_ANDX_SHARED_LOCK) posix_lock_type = CIFS_RDLCK; else posix_lock_type = CIFS_WRLCK; - if (numUnlock == 1) + if (unlock == 1) posix_lock_type = CIFS_UNLCK; - rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */, - length, pfLock, posix_lock_type, - wait_flag); - } else { - struct cifsFileInfo *fid = file->private_data; - - if (numLock) { - rc = CIFSSMBLock(xid, tcon, netfid, length, - pfLock->fl_start, 0, numLock, lockType, - wait_flag, 0); - - if (rc == 0) { - /* For Windows locks we must store them. */ - rc = store_file_lock(fid, length, - pfLock->fl_start, lockType); - } - } else if (numUnlock) { - /* For each stored lock that this unlock overlaps - completely, unlock it. */ - int stored_rc = 0; - struct cifsLockInfo *li, *tmp; + rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */, length, + flock, posix_lock_type, wait_flag); + goto out; + } - rc = 0; - mutex_lock(&fid->lock_mutex); - list_for_each_entry_safe(li, tmp, &fid->llist, llist) { - if (pfLock->fl_start <= li->offset && - (pfLock->fl_start + length) >= - (li->offset + li->length)) { - stored_rc = CIFSSMBLock(xid, tcon, - netfid, li->length, - li->offset, 1, 0, - li->type, false, 0); - if (stored_rc) - rc = stored_rc; - else { - list_del(&li->llist); - kfree(li); - } - } + if (lock) { + rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, length, + flock->fl_start, 0, lock, type, wait_flag, 0); + if (rc == 0) { + /* For Windows locks we must store them. */ + rc = store_file_lock(cfile, length, flock->fl_start, + type, netfid); + } + } else if (unlock) { + /* + * For each stored lock that this unlock overlaps completely, + * unlock it. + */ + int stored_rc = 0; + struct cifsLockInfo *li, *tmp; + + mutex_lock(&cfile->lock_mutex); + list_for_each_entry_safe(li, tmp, &cfile->llist, llist) { + if (flock->fl_start > li->offset || + (flock->fl_start + length) < + (li->offset + li->length)) + continue; + if (current->tgid != li->pid) + continue; + + stored_rc = CIFSSMBLock(xid, tcon, netfid, + current->tgid, li->length, + li->offset, 1, 0, li->type, + 0, 0); + if (stored_rc) + rc = stored_rc; + else { + list_del(&li->llist); + kfree(li); } - mutex_unlock(&fid->lock_mutex); } + mutex_unlock(&cfile->lock_mutex); + } +out: + if (flock->fl_flags & FL_POSIX) + 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; + __u8 type; + + rc = -EACCES; + xid = GetXid(); + + cFYI(1, "Lock parm: 0x%x flockflags: 0x%x flocktype: 0x%x start: %lld " + "end: %lld", cmd, flock->fl_flags, flock->fl_type, + flock->fl_start, flock->fl_end); + + cifs_read_flock(flock, &type, &lock, &unlock, &wait_flag); + + cifs_sb = CIFS_SB(file->f_path.dentry->d_sb); + cfile = (struct cifsFileInfo *)file->private_data; + tcon = tlink_tcon(cfile->tlink); + netfid = cfile->netfid; + cinode = CIFS_I(file->f_path.dentry->d_inode); + + if ((tcon->ses->capabilities & CAP_UNIX) && + (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(cfile, flock, type, wait_flag, posix_lck, xid); + FreeXid(xid); + return rc; + } + + if (!lock && !unlock) { + /* + * if no lock or unlock then nothing to do since we do not + * know what it is + */ + FreeXid(xid); + return -EOPNOTSUPP; } - if (pfLock->fl_flags & FL_POSIX) - posix_lock_file_wait(file, pfLock); + rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock, + xid); FreeXid(xid); return rc; } @@ -2423,8 +2454,9 @@ void cifs_oplock_break(struct work_struct *work) * disconnected since oplock already released by the server */ if (!cfile->oplock_break_cancelled) { - rc = CIFSSMBLock(0, tlink_tcon(cfile->tlink), cfile->netfid, 0, - 0, 0, 0, LOCKING_ANDX_OPLOCK_RELEASE, false, + rc = CIFSSMBLock(0, tlink_tcon(cfile->tlink), cfile->netfid, + current->tgid, 0, 0, 0, 0, + LOCKING_ANDX_OPLOCK_RELEASE, false, cinode->clientCanCacheRead ? 1 : 0); cFYI(1, "Oplock release rc = %d", rc); } -- 2.7.4