[mirror_ubuntu-focal-kernel.git] / fs / ceph / locks.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/ceph/ceph_debug.h>

#include <linux/file.h>
#include <linux/namei.h>
#include <linux/random.h>

#include "super.h"
#include "mds_client.h"
#include <linux/ceph/pagelist.h>

static u64 lock_secret;
static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
                                         struct ceph_mds_request *req);

static inline u64 secure_addr(void *addr)
{
	u64 v = lock_secret ^ (u64)(unsigned long)addr;
	/*
	 * Set the most significant bit, so that MDS knows the 'owner'
	 * is sufficient to identify the owner of lock. (old code uses
	 * both 'owner' and 'pid')
	 */
	v |= (1ULL << 63);
	return v;
}

void __init ceph_flock_init(void)
{
	get_random_bytes(&lock_secret, sizeof(lock_secret));
}

static void ceph_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
{
	struct ceph_file_info *fi = dst->fl_file->private_data;
	struct inode *inode = file_inode(dst->fl_file);
	atomic_inc(&ceph_inode(inode)->i_filelock_ref);
	atomic_inc(&fi->num_locks);
}

static void ceph_fl_release_lock(struct file_lock *fl)
{
	struct ceph_file_info *fi = fl->fl_file->private_data;
	struct inode *inode = file_inode(fl->fl_file);
	struct ceph_inode_info *ci = ceph_inode(inode);
	atomic_dec(&fi->num_locks);
	if (atomic_dec_and_test(&ci->i_filelock_ref)) {
		/* clear error when all locks are released */
		spin_lock(&ci->i_ceph_lock);
		ci->i_ceph_flags &= ~CEPH_I_ERROR_FILELOCK;
		spin_unlock(&ci->i_ceph_lock);
	}
}

static const struct file_lock_operations ceph_fl_lock_ops = {
	.fl_copy_lock = ceph_fl_copy_lock,
	.fl_release_private = ceph_fl_release_lock,
};

/**
 * Implement fcntl and flock locking functions.
 */
static int ceph_lock_message(u8 lock_type, u16 operation, struct inode *inode,
			     int cmd, u8 wait, struct file_lock *fl)
{
	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
	struct ceph_mds_request *req;
	int err;
	u64 length = 0;
	u64 owner;

	if (operation == CEPH_MDS_OP_SETFILELOCK) {
		/*
		 * increasing i_filelock_ref closes race window between
		 * handling request reply and adding file_lock struct to
		 * inode. Otherwise, auth caps may get trimmed in the
		 * window. Caller function will decrease the counter.
		 */
		fl->fl_ops = &ceph_fl_lock_ops;
		fl->fl_ops->fl_copy_lock(fl, NULL);
	}

	if (operation != CEPH_MDS_OP_SETFILELOCK || cmd == CEPH_LOCK_UNLOCK)
		wait = 0;

	req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
	if (IS_ERR(req))
		return PTR_ERR(req);
	req->r_inode = inode;
	ihold(inode);
	req->r_num_caps = 1;

	/* mds requires start and length rather than start and end */
	if (LLONG_MAX == fl->fl_end)
		length = 0;
	else
		length = fl->fl_end - fl->fl_start + 1;

	owner = secure_addr(fl->fl_owner);

	dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
	     "start: %llu, length: %llu, wait: %d, type: %d\n", (int)lock_type,
	     (int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
	     wait, fl->fl_type);

	req->r_args.filelock_change.rule = lock_type;
	req->r_args.filelock_change.type = cmd;
	req->r_args.filelock_change.owner = cpu_to_le64(owner);
	req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
	req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
	req->r_args.filelock_change.length = cpu_to_le64(length);
	req->r_args.filelock_change.wait = wait;

	if (wait)
		req->r_wait_for_completion = ceph_lock_wait_for_completion;

	err = ceph_mdsc_do_request(mdsc, inode, req);
	if (!err && operation == CEPH_MDS_OP_GETFILELOCK) {
		fl->fl_pid = -le64_to_cpu(req->r_reply_info.filelock_reply->pid);
		if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
			fl->fl_type = F_RDLCK;
		else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
			fl->fl_type = F_WRLCK;
		else
			fl->fl_type = F_UNLCK;

		fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
		length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
						 le64_to_cpu(req->r_reply_info.filelock_reply->length);
		if (length >= 1)
			fl->fl_end = length -1;
		else
			fl->fl_end = 0;

	}
	ceph_mdsc_put_request(req);
	dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
	     "length: %llu, wait: %d, type: %d, err code %d\n", (int)lock_type,
	     (int)operation, (u64)fl->fl_pid, fl->fl_start,
	     length, wait, fl->fl_type, err);
	return err;
}

static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
                                         struct ceph_mds_request *req)
{
	struct ceph_mds_request *intr_req;
	struct inode *inode = req->r_inode;
	int err, lock_type;

	BUG_ON(req->r_op != CEPH_MDS_OP_SETFILELOCK);
	if (req->r_args.filelock_change.rule == CEPH_LOCK_FCNTL)
		lock_type = CEPH_LOCK_FCNTL_INTR;
	else if (req->r_args.filelock_change.rule == CEPH_LOCK_FLOCK)
		lock_type = CEPH_LOCK_FLOCK_INTR;
	else
		BUG_ON(1);
	BUG_ON(req->r_args.filelock_change.type == CEPH_LOCK_UNLOCK);

	err = wait_for_completion_interruptible(&req->r_completion);
	if (!err)
		return 0;

	dout("ceph_lock_wait_for_completion: request %llu was interrupted\n",
	     req->r_tid);

	mutex_lock(&mdsc->mutex);
	if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
		err = 0;
	} else {
		/*
		 * ensure we aren't running concurrently with
		 * ceph_fill_trace or ceph_readdir_prepopulate, which
		 * rely on locks (dir mutex) held by our caller.
		 */
		mutex_lock(&req->r_fill_mutex);
		req->r_err = err;
		set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
		mutex_unlock(&req->r_fill_mutex);

		if (!req->r_session) {
			// haven't sent the request
			err = 0;
		}
	}
	mutex_unlock(&mdsc->mutex);
	if (!err)
		return 0;

	intr_req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETFILELOCK,
					    USE_AUTH_MDS);
	if (IS_ERR(intr_req))
		return PTR_ERR(intr_req);

	intr_req->r_inode = inode;
	ihold(inode);
	intr_req->r_num_caps = 1;

	intr_req->r_args.filelock_change = req->r_args.filelock_change;
	intr_req->r_args.filelock_change.rule = lock_type;
	intr_req->r_args.filelock_change.type = CEPH_LOCK_UNLOCK;

	err = ceph_mdsc_do_request(mdsc, inode, intr_req);
	ceph_mdsc_put_request(intr_req);

	if (err && err != -ERESTARTSYS)
		return err;

	wait_for_completion_killable(&req->r_safe_completion);
	return 0;
}

/**
 * Attempt to set an fcntl lock.
 * For now, this just goes away to the server. Later it may be more awesome.
 */
int ceph_lock(struct file *file, int cmd, struct file_lock *fl)
{
	struct inode *inode = file_inode(file);
	struct ceph_inode_info *ci = ceph_inode(inode);
	int err = 0;
	u16 op = CEPH_MDS_OP_SETFILELOCK;
	u8 wait = 0;
	u8 lock_cmd;

	if (!(fl->fl_flags & FL_POSIX))
		return -ENOLCK;
	/* No mandatory locks */
	if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
		return -ENOLCK;

	dout("ceph_lock, fl_owner: %p\n", fl->fl_owner);

	/* set wait bit as appropriate, then make command as Ceph expects it*/
	if (IS_GETLK(cmd))
		op = CEPH_MDS_OP_GETFILELOCK;
	else if (IS_SETLKW(cmd))
		wait = 1;

	spin_lock(&ci->i_ceph_lock);
	if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
		err = -EIO;
	}
	spin_unlock(&ci->i_ceph_lock);
	if (err < 0) {
		if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK == fl->fl_type)
			posix_lock_file(file, fl, NULL);
		return err;
	}

	if (F_RDLCK == fl->fl_type)
		lock_cmd = CEPH_LOCK_SHARED;
	else if (F_WRLCK == fl->fl_type)
		lock_cmd = CEPH_LOCK_EXCL;
	else
		lock_cmd = CEPH_LOCK_UNLOCK;

	err = ceph_lock_message(CEPH_LOCK_FCNTL, op, inode, lock_cmd, wait, fl);
	if (!err) {
		if (op == CEPH_MDS_OP_SETFILELOCK) {
			dout("mds locked, locking locally\n");
			err = posix_lock_file(file, fl, NULL);
			if (err) {
				/* undo! This should only happen if
				 * the kernel detects local
				 * deadlock. */
				ceph_lock_message(CEPH_LOCK_FCNTL, op, inode,
						  CEPH_LOCK_UNLOCK, 0, fl);
				dout("got %d on posix_lock_file, undid lock\n",
				     err);
			}
		}
	}
	return err;
}

int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
{
	struct inode *inode = file_inode(file);
	struct ceph_inode_info *ci = ceph_inode(inode);
	int err = 0;
	u8 wait = 0;
	u8 lock_cmd;

	if (!(fl->fl_flags & FL_FLOCK))
		return -ENOLCK;
	/* No mandatory locks */
	if (fl->fl_type & LOCK_MAND)
		return -EOPNOTSUPP;

	dout("ceph_flock, fl_file: %p\n", fl->fl_file);

	spin_lock(&ci->i_ceph_lock);
	if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
		err = -EIO;
	}
	spin_unlock(&ci->i_ceph_lock);
	if (err < 0) {
		if (F_UNLCK == fl->fl_type)
			locks_lock_file_wait(file, fl);
		return err;
	}

	if (IS_SETLKW(cmd))
		wait = 1;

	if (F_RDLCK == fl->fl_type)
		lock_cmd = CEPH_LOCK_SHARED;
	else if (F_WRLCK == fl->fl_type)
		lock_cmd = CEPH_LOCK_EXCL;
	else
		lock_cmd = CEPH_LOCK_UNLOCK;

	err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
				inode, lock_cmd, wait, fl);
	if (!err) {
		err = locks_lock_file_wait(file, fl);
		if (err) {
			ceph_lock_message(CEPH_LOCK_FLOCK,
					  CEPH_MDS_OP_SETFILELOCK,
					  inode, CEPH_LOCK_UNLOCK, 0, fl);
			dout("got %d on locks_lock_file_wait, undid lock\n", err);
		}
	}
	return err;
}

/*
 * Fills in the passed counter variables, so you can prepare pagelist metadata
 * before calling ceph_encode_locks.
 */
void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
{
	struct file_lock *lock;
	struct file_lock_context *ctx;

	*fcntl_count = 0;
	*flock_count = 0;

	ctx = inode->i_flctx;
	if (ctx) {
		spin_lock(&ctx->flc_lock);
		list_for_each_entry(lock, &ctx->flc_posix, fl_list)
			++(*fcntl_count);
		list_for_each_entry(lock, &ctx->flc_flock, fl_list)
			++(*flock_count);
		spin_unlock(&ctx->flc_lock);
	}
	dout("counted %d flock locks and %d fcntl locks\n",
	     *flock_count, *fcntl_count);
}

/*
 * Given a pointer to a lock, convert it to a ceph filelock
 */
static int lock_to_ceph_filelock(struct file_lock *lock,
				 struct ceph_filelock *cephlock)
{
	int err = 0;
	cephlock->start = cpu_to_le64(lock->fl_start);
	cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
	cephlock->client = cpu_to_le64(0);
	cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
	cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));

	switch (lock->fl_type) {
	case F_RDLCK:
		cephlock->type = CEPH_LOCK_SHARED;
		break;
	case F_WRLCK:
		cephlock->type = CEPH_LOCK_EXCL;
		break;
	case F_UNLCK:
		cephlock->type = CEPH_LOCK_UNLOCK;
		break;
	default:
		dout("Have unknown lock type %d\n", lock->fl_type);
		err = -EINVAL;
	}

	return err;
}

/**
 * Encode the flock and fcntl locks for the given inode into the ceph_filelock
 * array. Must be called with inode->i_lock already held.
 * If we encounter more of a specific lock type than expected, return -ENOSPC.
 */
int ceph_encode_locks_to_buffer(struct inode *inode,
				struct ceph_filelock *flocks,
				int num_fcntl_locks, int num_flock_locks)
{
	struct file_lock *lock;
	struct file_lock_context *ctx = inode->i_flctx;
	int err = 0;
	int seen_fcntl = 0;
	int seen_flock = 0;
	int l = 0;

	dout("encoding %d flock and %d fcntl locks\n", num_flock_locks,
	     num_fcntl_locks);

	if (!ctx)
		return 0;

	spin_lock(&ctx->flc_lock);
	list_for_each_entry(lock, &ctx->flc_posix, fl_list) {
		++seen_fcntl;
		if (seen_fcntl > num_fcntl_locks) {
			err = -ENOSPC;
			goto fail;
		}
		err = lock_to_ceph_filelock(lock, &flocks[l]);
		if (err)
			goto fail;
		++l;
	}
	list_for_each_entry(lock, &ctx->flc_flock, fl_list) {
		++seen_flock;
		if (seen_flock > num_flock_locks) {
			err = -ENOSPC;
			goto fail;
		}
		err = lock_to_ceph_filelock(lock, &flocks[l]);
		if (err)
			goto fail;
		++l;
	}
fail:
	spin_unlock(&ctx->flc_lock);
	return err;
}

/**
 * Copy the encoded flock and fcntl locks into the pagelist.
 * Format is: #fcntl locks, sequential fcntl locks, #flock locks,
 * sequential flock locks.
 * Returns zero on success.
 */
int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
			   struct ceph_pagelist *pagelist,
			   int num_fcntl_locks, int num_flock_locks)
{
	int err = 0;
	__le32 nlocks;

	nlocks = cpu_to_le32(num_fcntl_locks);
	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
	if (err)
		goto out_fail;

	if (num_fcntl_locks > 0) {
		err = ceph_pagelist_append(pagelist, flocks,
					   num_fcntl_locks * sizeof(*flocks));
		if (err)
			goto out_fail;
	}

	nlocks = cpu_to_le32(num_flock_locks);
	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
	if (err)
		goto out_fail;

	if (num_flock_locks > 0) {
		err = ceph_pagelist_append(pagelist, &flocks[num_fcntl_locks],
					   num_flock_locks * sizeof(*flocks));
	}
out_fail:
	return err;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
3d14c5d2	2	#include <linux/ceph/ceph_debug.h>
40819f6f GF	3
	4	#include <linux/file.h>
	5	#include <linux/namei.h>
eb13e832	6	#include <linux/random.h>
40819f6f GF	7
	8	#include "super.h"
	9	#include "mds_client.h"
3d14c5d2	10	#include <linux/ceph/pagelist.h>
40819f6f	11
eb13e832	12	static u64 lock_secret;
9280be24 YZ	13	static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
9280be24 YZ	14	struct ceph_mds_request *req);
eb13e832 YZ	15
	16	static inline u64 secure_addr(void *addr)
	17	{
	18	u64 v = lock_secret ^ (u64)(unsigned long)addr;
	19	/*
	20	* Set the most significant bit, so that MDS knows the 'owner'
	21	* is sufficient to identify the owner of lock. (old code uses
	22	* both 'owner' and 'pid')
	23	*/
	24	v \|= (1ULL << 63);
	25	return v;
	26	}
	27
	28	void __init ceph_flock_init(void)
	29	{
	30	get_random_bytes(&lock_secret, sizeof(lock_secret));
	31	}
	32
89aa5930 YZ	33	static void ceph_fl_copy_lock(struct file_lock dst, struct file_lock src)
89aa5930 YZ	34	{
ff5d913d YZ	35	struct ceph_file_info *fi = dst->fl_file->private_data;
ff5d913d YZ	36	struct inode *inode = file_inode(dst->fl_file);
89aa5930	37	atomic_inc(&ceph_inode(inode)->i_filelock_ref);
ff5d913d	38	atomic_inc(&fi->num_locks);
89aa5930 YZ	39	}
	40
	41	static void ceph_fl_release_lock(struct file_lock *fl)
	42	{
ff5d913d	43	struct ceph_file_info *fi = fl->fl_file->private_data;
89aa5930	44	struct inode *inode = file_inode(fl->fl_file);
b3f8d68f	45	struct ceph_inode_info *ci = ceph_inode(inode);
ff5d913d	46	atomic_dec(&fi->num_locks);
b3f8d68f YZ	47	if (atomic_dec_and_test(&ci->i_filelock_ref)) {
	48	/* clear error when all locks are released */
	49	spin_lock(&ci->i_ceph_lock);
	50	ci->i_ceph_flags &= ~CEPH_I_ERROR_FILELOCK;
	51	spin_unlock(&ci->i_ceph_lock);
	52	}
89aa5930 YZ	53	}
	54
	55	static const struct file_lock_operations ceph_fl_lock_ops = {
	56	.fl_copy_lock = ceph_fl_copy_lock,
	57	.fl_release_private = ceph_fl_release_lock,
	58	};
	59
40819f6f GF	60	/**
	61	* Implement fcntl and flock locking functions.
	62	*/
89aa5930	63	static int ceph_lock_message(u8 lock_type, u16 operation, struct inode *inode,
637ae8d5	64	int cmd, u8 wait, struct file_lock *fl)
40819f6f	65	{
eb13e832	66	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
40819f6f GF	67	struct ceph_mds_request *req;
40819f6f GF	68	int err;
637ae8d5	69	u64 length = 0;
eb13e832	70	u64 owner;
40819f6f	71
89aa5930 YZ	72	if (operation == CEPH_MDS_OP_SETFILELOCK) {
	73	/*
	74	* increasing i_filelock_ref closes race window between
	75	* handling request reply and adding file_lock struct to
	76	* inode. Otherwise, auth caps may get trimmed in the
	77	* window. Caller function will decrease the counter.
	78	*/
	79	fl->fl_ops = &ceph_fl_lock_ops;
ff5d913d	80	fl->fl_ops->fl_copy_lock(fl, NULL);
89aa5930 YZ	81	}
89aa5930 YZ	82
9280be24 YZ	83	if (operation != CEPH_MDS_OP_SETFILELOCK \|\| cmd == CEPH_LOCK_UNLOCK)
	84	wait = 0;
	85
40819f6f GF	86	req = ceph_mdsc_create_request(mdsc, operation, USE_AUTH_MDS);
	87	if (IS_ERR(req))
	88	return PTR_ERR(req);
70b666c3 SW	89	req->r_inode = inode;
70b666c3 SW	90	ihold(inode);
3bd58143	91	req->r_num_caps = 1;
40819f6f	92
637ae8d5 HS	93	/* mds requires start and length rather than start and end */
	94	if (LLONG_MAX == fl->fl_end)
	95	length = 0;
	96	else
	97	length = fl->fl_end - fl->fl_start + 1;
	98
130d1f95	99	owner = secure_addr(fl->fl_owner);
eb13e832 YZ	100
eb13e832 YZ	101	dout("ceph_lock_message: rule: %d, op: %d, owner: %llx, pid: %llu, "
4c069a58	102	"start: %llu, length: %llu, wait: %d, type: %d\n", (int)lock_type,
eb13e832 YZ	103	(int)operation, owner, (u64)fl->fl_pid, fl->fl_start, length,
eb13e832 YZ	104	wait, fl->fl_type);
637ae8d5	105
40819f6f GF	106	req->r_args.filelock_change.rule = lock_type;
40819f6f GF	107	req->r_args.filelock_change.type = cmd;
eb13e832	108	req->r_args.filelock_change.owner = cpu_to_le64(owner);
637ae8d5	109	req->r_args.filelock_change.pid = cpu_to_le64((u64)fl->fl_pid);
637ae8d5	110	req->r_args.filelock_change.start = cpu_to_le64(fl->fl_start);
40819f6f GF	111	req->r_args.filelock_change.length = cpu_to_le64(length);
	112	req->r_args.filelock_change.wait = wait;
	113
9280be24 YZ	114	if (wait)
	115	req->r_wait_for_completion = ceph_lock_wait_for_completion;
	116
40819f6f	117	err = ceph_mdsc_do_request(mdsc, inode, req);
28a28261	118	if (!err && operation == CEPH_MDS_OP_GETFILELOCK) {
9d5b86ac	119	fl->fl_pid = -le64_to_cpu(req->r_reply_info.filelock_reply->pid);
a5b10629 HS	120	if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
	121	fl->fl_type = F_RDLCK;
	122	else if (CEPH_LOCK_EXCL == req->r_reply_info.filelock_reply->type)
	123	fl->fl_type = F_WRLCK;
	124	else
	125	fl->fl_type = F_UNLCK;
	126
	127	fl->fl_start = le64_to_cpu(req->r_reply_info.filelock_reply->start);
	128	length = le64_to_cpu(req->r_reply_info.filelock_reply->start) +
	129	le64_to_cpu(req->r_reply_info.filelock_reply->length);
	130	if (length >= 1)
	131	fl->fl_end = length -1;
	132	else
	133	fl->fl_end = 0;
	134
	135	}
40819f6f GF	136	ceph_mdsc_put_request(req);
40819f6f GF	137	dout("ceph_lock_message: rule: %d, op: %d, pid: %llu, start: %llu, "
4c069a58	138	"length: %llu, wait: %d, type: %d, err code %d\n", (int)lock_type,
637ae8d5 HS	139	(int)operation, (u64)fl->fl_pid, fl->fl_start,
637ae8d5 HS	140	length, wait, fl->fl_type, err);
40819f6f GF	141	return err;
	142	}
	143
9280be24 YZ	144	static int ceph_lock_wait_for_completion(struct ceph_mds_client *mdsc,
	145	struct ceph_mds_request *req)
	146	{
	147	struct ceph_mds_request *intr_req;
	148	struct inode *inode = req->r_inode;
	149	int err, lock_type;
	150
	151	BUG_ON(req->r_op != CEPH_MDS_OP_SETFILELOCK);
	152	if (req->r_args.filelock_change.rule == CEPH_LOCK_FCNTL)
	153	lock_type = CEPH_LOCK_FCNTL_INTR;
	154	else if (req->r_args.filelock_change.rule == CEPH_LOCK_FLOCK)
	155	lock_type = CEPH_LOCK_FLOCK_INTR;
	156	else
	157	BUG_ON(1);
	158	BUG_ON(req->r_args.filelock_change.type == CEPH_LOCK_UNLOCK);
	159
	160	err = wait_for_completion_interruptible(&req->r_completion);
	161	if (!err)
	162	return 0;
	163
	164	dout("ceph_lock_wait_for_completion: request %llu was interrupted\n",
	165	req->r_tid);
	166
92e57e62 YZ	167	mutex_lock(&mdsc->mutex);
	168	if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
	169	err = 0;
	170	} else {
	171	/*
	172	* ensure we aren't running concurrently with
	173	* ceph_fill_trace or ceph_readdir_prepopulate, which
	174	* rely on locks (dir mutex) held by our caller.
	175	*/
	176	mutex_lock(&req->r_fill_mutex);
	177	req->r_err = err;
	178	set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
	179	mutex_unlock(&req->r_fill_mutex);
	180
	181	if (!req->r_session) {
	182	// haven't sent the request
	183	err = 0;
	184	}
	185	}
	186	mutex_unlock(&mdsc->mutex);
	187	if (!err)
	188	return 0;
	189
9280be24 YZ	190	intr_req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETFILELOCK,
	191	USE_AUTH_MDS);
	192	if (IS_ERR(intr_req))
	193	return PTR_ERR(intr_req);
	194
	195	intr_req->r_inode = inode;
	196	ihold(inode);
	197	intr_req->r_num_caps = 1;
	198
	199	intr_req->r_args.filelock_change = req->r_args.filelock_change;
	200	intr_req->r_args.filelock_change.rule = lock_type;
	201	intr_req->r_args.filelock_change.type = CEPH_LOCK_UNLOCK;
	202
	203	err = ceph_mdsc_do_request(mdsc, inode, intr_req);
	204	ceph_mdsc_put_request(intr_req);
	205
	206	if (err && err != -ERESTARTSYS)
	207	return err;
	208
92e57e62	209	wait_for_completion_killable(&req->r_safe_completion);
9280be24 YZ	210	return 0;
	211	}
	212
40819f6f GF	213	/**
	214	* Attempt to set an fcntl lock.
	215	* For now, this just goes away to the server. Later it may be more awesome.
	216	*/
	217	int ceph_lock(struct file file, int cmd, struct file_lock fl)
	218	{
89aa5930	219	struct inode *inode = file_inode(file);
b3f8d68f YZ	220	struct ceph_inode_info *ci = ceph_inode(inode);
b3f8d68f YZ	221	int err = 0;
40819f6f	222	u16 op = CEPH_MDS_OP_SETFILELOCK;
89aa5930	223	u8 wait = 0;
b3f8d68f	224	u8 lock_cmd;
40819f6f	225
eb70c0ce YZ	226	if (!(fl->fl_flags & FL_POSIX))
	227	return -ENOLCK;
	228	/* No mandatory locks */
	229	if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
	230	return -ENOLCK;
	231
4c069a58	232	dout("ceph_lock, fl_owner: %p\n", fl->fl_owner);
40819f6f GF	233
40819f6f GF	234	/* set wait bit as appropriate, then make command as Ceph expects it*/
0e8e95d6	235	if (IS_GETLK(cmd))
40819f6f	236	op = CEPH_MDS_OP_GETFILELOCK;
0e8e95d6 YZ	237	else if (IS_SETLKW(cmd))
0e8e95d6 YZ	238	wait = 1;
40819f6f	239
b3f8d68f YZ	240	spin_lock(&ci->i_ceph_lock);
	241	if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
	242	err = -EIO;
b3f8d68f YZ	243	}
	244	spin_unlock(&ci->i_ceph_lock);
	245	if (err < 0) {
	246	if (op == CEPH_MDS_OP_SETFILELOCK && F_UNLCK == fl->fl_type)
	247	posix_lock_file(file, fl, NULL);
	248	return err;
89aa5930 YZ	249	}
89aa5930 YZ	250
40819f6f GF	251	if (F_RDLCK == fl->fl_type)
	252	lock_cmd = CEPH_LOCK_SHARED;
	253	else if (F_WRLCK == fl->fl_type)
	254	lock_cmd = CEPH_LOCK_EXCL;
	255	else
	256	lock_cmd = CEPH_LOCK_UNLOCK;
	257
89aa5930	258	err = ceph_lock_message(CEPH_LOCK_FCNTL, op, inode, lock_cmd, wait, fl);
40819f6f	259	if (!err) {
b3f8d68f	260	if (op == CEPH_MDS_OP_SETFILELOCK) {
4c069a58	261	dout("mds locked, locking locally\n");
a5b10629	262	err = posix_lock_file(file, fl, NULL);
b3f8d68f	263	if (err) {
0c1f91f2 SW	264	/* undo! This should only happen if
	265	* the kernel detects local
	266	* deadlock. */
89aa5930	267	ceph_lock_message(CEPH_LOCK_FCNTL, op, inode,
a5b10629	268	CEPH_LOCK_UNLOCK, 0, fl);
4c069a58	269	dout("got %d on posix_lock_file, undid lock\n",
0c1f91f2	270	err);
a5b10629	271	}
40819f6f	272	}
40819f6f GF	273	}
	274	return err;
	275	}
	276
	277	int ceph_flock(struct file file, int cmd, struct file_lock fl)
	278	{
89aa5930	279	struct inode *inode = file_inode(file);
b3f8d68f YZ	280	struct ceph_inode_info *ci = ceph_inode(inode);
b3f8d68f YZ	281	int err = 0;
0e8e95d6	282	u8 wait = 0;
b3f8d68f	283	u8 lock_cmd;
40819f6f	284
eb70c0ce YZ	285	if (!(fl->fl_flags & FL_FLOCK))
	286	return -ENOLCK;
	287	/* No mandatory locks */
db4a63aa YZ	288	if (fl->fl_type & LOCK_MAND)
db4a63aa YZ	289	return -EOPNOTSUPP;
eb70c0ce	290
4c069a58	291	dout("ceph_flock, fl_file: %p\n", fl->fl_file);
40819f6f	292
b3f8d68f YZ	293	spin_lock(&ci->i_ceph_lock);
	294	if (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK) {
	295	err = -EIO;
b3f8d68f YZ	296	}
	297	spin_unlock(&ci->i_ceph_lock);
	298	if (err < 0) {
	299	if (F_UNLCK == fl->fl_type)
	300	locks_lock_file_wait(file, fl);
	301	return err;
	302	}
89aa5930	303
0e8e95d6 YZ	304	if (IS_SETLKW(cmd))
	305	wait = 1;
	306
	307	if (F_RDLCK == fl->fl_type)
40819f6f	308	lock_cmd = CEPH_LOCK_SHARED;
0e8e95d6	309	else if (F_WRLCK == fl->fl_type)
40819f6f GF	310	lock_cmd = CEPH_LOCK_EXCL;
	311	else
	312	lock_cmd = CEPH_LOCK_UNLOCK;
40819f6f GF	313
40819f6f GF	314	err = ceph_lock_message(CEPH_LOCK_FLOCK, CEPH_MDS_OP_SETFILELOCK,
89aa5930	315	inode, lock_cmd, wait, fl);
40819f6f	316	if (!err) {
4f656367	317	err = locks_lock_file_wait(file, fl);
40819f6f GF	318	if (err) {
	319	ceph_lock_message(CEPH_LOCK_FLOCK,
	320	CEPH_MDS_OP_SETFILELOCK,
89aa5930	321	inode, CEPH_LOCK_UNLOCK, 0, fl);
4c069a58	322	dout("got %d on locks_lock_file_wait, undid lock\n", err);
40819f6f	323	}
40819f6f GF	324	}
	325	return err;
	326	}
	327
5263e31e JL	328	/*
	329	* Fills in the passed counter variables, so you can prepare pagelist metadata
	330	* before calling ceph_encode_locks.
40819f6f GF	331	*/
	332	void ceph_count_locks(struct inode inode, int fcntl_count, int *flock_count)
	333	{
e084c1bd	334	struct file_lock *lock;
5263e31e	335	struct file_lock_context *ctx;
40819f6f GF	336
	337	*fcntl_count = 0;
	338	*flock_count = 0;
	339
5263e31e JL	340	ctx = inode->i_flctx;
5263e31e JL	341	if (ctx) {
e084c1bd JL	342	spin_lock(&ctx->flc_lock);
	343	list_for_each_entry(lock, &ctx->flc_posix, fl_list)
	344	++(*fcntl_count);
	345	list_for_each_entry(lock, &ctx->flc_flock, fl_list)
	346	++(*flock_count);
	347	spin_unlock(&ctx->flc_lock);
40819f6f	348	}
4c069a58	349	dout("counted %d flock locks and %d fcntl locks\n",
40819f6f GF	350	flock_count, fcntl_count);
	351	}
	352
c6db8472 YZ	353	/*
	354	* Given a pointer to a lock, convert it to a ceph filelock
	355	*/
	356	static int lock_to_ceph_filelock(struct file_lock *lock,
	357	struct ceph_filelock *cephlock)
	358	{
	359	int err = 0;
	360	cephlock->start = cpu_to_le64(lock->fl_start);
	361	cephlock->length = cpu_to_le64(lock->fl_end - lock->fl_start + 1);
	362	cephlock->client = cpu_to_le64(0);
	363	cephlock->pid = cpu_to_le64((u64)lock->fl_pid);
	364	cephlock->owner = cpu_to_le64(secure_addr(lock->fl_owner));
	365
	366	switch (lock->fl_type) {
	367	case F_RDLCK:
	368	cephlock->type = CEPH_LOCK_SHARED;
	369	break;
	370	case F_WRLCK:
	371	cephlock->type = CEPH_LOCK_EXCL;
	372	break;
	373	case F_UNLCK:
	374	cephlock->type = CEPH_LOCK_UNLOCK;
	375	break;
	376	default:
4c069a58	377	dout("Have unknown lock type %d\n", lock->fl_type);
c6db8472 YZ	378	err = -EINVAL;
	379	}
	380
	381	return err;
	382	}
	383
40819f6f	384	/**
39be95e9	385	* Encode the flock and fcntl locks for the given inode into the ceph_filelock
1c8c601a	386	* array. Must be called with inode->i_lock already held.
39be95e9	387	* If we encounter more of a specific lock type than expected, return -ENOSPC.
40819f6f	388	*/
39be95e9 JS	389	int ceph_encode_locks_to_buffer(struct inode *inode,
	390	struct ceph_filelock *flocks,
	391	int num_fcntl_locks, int num_flock_locks)
40819f6f GF	392	{
40819f6f GF	393	struct file_lock *lock;
bd61e0a9	394	struct file_lock_context *ctx = inode->i_flctx;
40819f6f	395	int err = 0;
fca4451a GF	396	int seen_fcntl = 0;
fca4451a GF	397	int seen_flock = 0;
39be95e9	398	int l = 0;
40819f6f	399
4c069a58	400	dout("encoding %d flock and %d fcntl locks\n", num_flock_locks,
40819f6f	401	num_fcntl_locks);
39be95e9	402
bd61e0a9 JL	403	if (!ctx)
	404	return 0;
	405
6109c850	406	spin_lock(&ctx->flc_lock);
f6762cb2	407	list_for_each_entry(lock, &ctx->flc_posix, fl_list) {
bd61e0a9 JL	408	++seen_fcntl;
	409	if (seen_fcntl > num_fcntl_locks) {
	410	err = -ENOSPC;
	411	goto fail;
40819f6f	412	}
bd61e0a9 JL	413	err = lock_to_ceph_filelock(lock, &flocks[l]);
	414	if (err)
	415	goto fail;
	416	++l;
40819f6f	417	}
bd61e0a9 JL	418	list_for_each_entry(lock, &ctx->flc_flock, fl_list) {
	419	++seen_flock;
	420	if (seen_flock > num_flock_locks) {
	421	err = -ENOSPC;
	422	goto fail;
40819f6f	423	}
bd61e0a9 JL	424	err = lock_to_ceph_filelock(lock, &flocks[l]);
	425	if (err)
	426	goto fail;
	427	++l;
40819f6f GF	428	}
40819f6f GF	429	fail:
6109c850	430	spin_unlock(&ctx->flc_lock);
40819f6f GF	431	return err;
	432	}
	433
39be95e9 JS	434	/**
	435	* Copy the encoded flock and fcntl locks into the pagelist.
	436	* Format is: #fcntl locks, sequential fcntl locks, #flock locks,
	437	* sequential flock locks.
	438	* Returns zero on success.
	439	*/
	440	int ceph_locks_to_pagelist(struct ceph_filelock *flocks,
	441	struct ceph_pagelist *pagelist,
	442	int num_fcntl_locks, int num_flock_locks)
	443	{
	444	int err = 0;
	445	__le32 nlocks;
	446
	447	nlocks = cpu_to_le32(num_fcntl_locks);
	448	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
	449	if (err)
	450	goto out_fail;
	451
4deb14a2 YZ	452	if (num_fcntl_locks > 0) {
	453	err = ceph_pagelist_append(pagelist, flocks,
	454	num_fcntl_locks * sizeof(*flocks));
	455	if (err)
	456	goto out_fail;
	457	}
39be95e9 JS	458
	459	nlocks = cpu_to_le32(num_flock_locks);
	460	err = ceph_pagelist_append(pagelist, &nlocks, sizeof(nlocks));
	461	if (err)
	462	goto out_fail;
	463
4deb14a2 YZ	464	if (num_flock_locks > 0) {
	465	err = ceph_pagelist_append(pagelist, &flocks[num_fcntl_locks],
	466	num_flock_locks * sizeof(*flocks));
	467	}
39be95e9 JS	468	out_fail:
	469	return err;
	470	}