Commit 03776f45 authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Steve French
Browse files

CIFS: Simplify byte range locking code 



Split cifs_lock into several functions and let CIFSSMBLock get pid
as an argument.

Signed-off-by: default avatarPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent 94443f43

fs/cifs/cifsglob.h

+1 −0
Original line number Diff line number Diff line
@@ -492,6 +492,7 @@ struct cifsLockInfo { 
	struct list_head llist;	/* pointer to next cifsLockInfo */

	__u64 offset;

	__u64 length;

	__u32 pid;

	__u8 type;

};

fs/cifs/cifsproto.h

+1 −1
Original line number Diff line number Diff line
@@ -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);

fs/cifs/cifssmb.c

+2 −2
Original line number Diff line number Diff line
@@ -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));

fs/cifs/file.c

+201 −169
Original line number Diff line number Diff line
@@ -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);
@@ -648,196 +648,173 @@ 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)

	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;

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 ((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) {

	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;

		rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,

					length, pfLock, posix_lock_type,

				      length, flock, 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);

	rc = CIFSSMBLock(xid, tcon, netfid, current->tgid, length,

			 flock->fl_start, 0, 1, type, 0, 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;

		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;

	}



		} else {

			/* if rc == ERR_SHARING_VIOLATION ? */

	if (type & LOCKING_ANDX_SHARED_LOCK) {

		flock->fl_type = F_WRLCK;

		rc = 0;

		return rc;

	}



			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);

	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,

						length, pfLock->fl_start, 1, 0,

						lockType |

						LOCKING_ANDX_SHARED_LOCK,

						0 /* wait flag */, 0);

					pfLock->fl_type = F_RDLCK;

		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);

					rc = 0;

				} else {

					pfLock->fl_type = F_WRLCK;

					rc = 0;

				}

			}

		}

			cERROR(1, "Error unlocking previously locked "

				  "range %d during test of lock", rc);

	} else

		flock->fl_type = F_WRLCK;



		FreeXid(xid);

	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;

	}

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_locking) {

	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);

		rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */, length,

				      flock, posix_lock_type, wait_flag);

		goto out;

	}



	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(fid, length,

						pfLock->fl_start, lockType);

			rc = store_file_lock(cfile, length, flock->fl_start,

					     type, netfid);

		}

		} else if (numUnlock) {

			/* For each stored lock that this unlock overlaps

			   completely, unlock it. */

	} else if (unlock) {

		/*

		 * For each stored lock that this unlock overlaps completely,

		 * unlock it.

		 */

		int stored_rc = 0;

		struct cifsLockInfo *li, *tmp;



			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);

		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 {
@@ -845,13 +822,67 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock) 
				kfree(li);

			}

		}

		mutex_unlock(&cfile->lock_mutex);

	}

			mutex_unlock(&fid->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);

	}