本文整理汇总了C++中IS_SETLKW函数的典型用法代码示例。如果您正苦于以下问题:C++ IS_SETLKW函数的具体用法?C++ IS_SETLKW怎么用?C++ IS_SETLKW使用的例子?那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。
在下文中一共展示了IS_SETLKW函数的13个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于我们的系统推荐出更棒的C++代码示例。
示例1: v9fs_file_flock_dotl
static int v9fs_file_flock_dotl(struct file *filp, int cmd,
struct file_lock *fl)
{
struct inode *inode = file_inode(filp);
int ret = -ENOLCK;
p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
filp, cmd, fl, filp);
/* No mandatory locks */
if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
goto out_err;
if (!(fl->fl_flags & FL_FLOCK))
goto out_err;
if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
filemap_write_and_wait(inode->i_mapping);
invalidate_mapping_pages(&inode->i_data, 0, -1);
}
/* Convert flock to posix lock */
fl->fl_flags |= FL_POSIX;
fl->fl_flags ^= FL_FLOCK;
if (IS_SETLK(cmd) | IS_SETLKW(cmd))
ret = v9fs_file_do_lock(filp, cmd, fl);
else
ret = -EINVAL;
out_err:
return ret;
}
开发者ID:AshishNamdev,项目名称:linux,代码行数:31,代码来源:vfs_file.c
示例2: ocfs2_do_flock
static int ocfs2_do_flock(struct file *file, struct inode *inode,
int cmd, struct file_lock *fl)
{
int ret = 0, level = 0, trylock = 0;
struct ocfs2_file_private *fp = file->private_data;
struct ocfs2_lock_res *lockres = &fp->fp_flock;
if (fl->fl_type == F_WRLCK)
level = 1;
if (!IS_SETLKW(cmd))
trylock = 1;
mutex_lock(&fp->fp_mutex);
if (lockres->l_flags & OCFS2_LOCK_ATTACHED &&
lockres->l_level > LKM_NLMODE) {
int old_level = 0;
if (lockres->l_level == LKM_EXMODE)
old_level = 1;
if (level == old_level)
goto out;
/*
* Converting an existing lock is not guaranteed to be
* atomic, so we can get away with simply unlocking
* here and allowing the lock code to try at the new
* level.
*/
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
开发者ID:johnny,项目名称:CobraDroidBeta,代码行数:33,代码来源:locks.c
示例3: ocfs2_do_flock
static int ocfs2_do_flock(struct file *file, struct inode *inode,
int cmd, struct file_lock *fl)
{
int ret = 0, level = 0, trylock = 0;
struct ocfs2_file_private *fp = file->private_data;
struct ocfs2_lock_res *lockres = &fp->fp_flock;
if (fl->fl_type == F_WRLCK)
level = 1;
if (!IS_SETLKW(cmd))
trylock = 1;
mutex_lock(&fp->fp_mutex);
if (lockres->l_flags & OCFS2_LOCK_ATTACHED &&
lockres->l_level > LKM_NLMODE) {
int old_level = 0;
if (lockres->l_level == LKM_EXMODE)
old_level = 1;
if (level == old_level)
goto out;
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
开发者ID:MiniBlu,项目名称:cm11_kernel_htc_msm8974a3ul,代码行数:27,代码来源:locks.c
示例4: gfs2_lock
static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
struct lm_lockname name =
{ .ln_number = ip->i_num.no_addr,
.ln_type = LM_TYPE_PLOCK };
if (!(fl->fl_flags & FL_POSIX))
return -ENOLCK;
if ((ip->i_inode.i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
return -ENOLCK;
if (sdp->sd_args.ar_localflocks) {
if (IS_GETLK(cmd)) {
struct file_lock tmp;
int ret;
ret = posix_test_lock(file, fl, &tmp);
fl->fl_type = F_UNLCK;
if (ret)
memcpy(fl, &tmp, sizeof(struct file_lock));
return 0;
} else {
return posix_lock_file_wait(file, fl);
}
}
if (IS_GETLK(cmd))
return gfs2_lm_plock_get(sdp, &name, file, fl);
else if (fl->fl_type == F_UNLCK)
return gfs2_lm_punlock(sdp, &name, file, fl);
else
return gfs2_lm_plock(sdp, &name, file, cmd, fl);
}
static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_file *fp = file->private_data;
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
struct gfs2_glock *gl;
unsigned int state;
int flags;
int error = 0;
state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
mutex_lock(&fp->f_fl_mutex);
gl = fl_gh->gh_gl;
if (gl) {
if (fl_gh->gh_state == state)
goto out;
gfs2_glock_hold(gl);
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
gfs2_glock_dq_uninit(fl_gh);
} else {
开发者ID:WiseMan787,项目名称:ralink_sdk,代码行数:59,代码来源:ops_file.c
示例5: ceph_lock
/**
* 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)
{
u8 lock_cmd;
int err;
u8 wait = 0;
u16 op = CEPH_MDS_OP_SETFILELOCK;
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", 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;
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, file, lock_cmd, wait, fl);
if (!err) {
if (op != CEPH_MDS_OP_GETFILELOCK) {
dout("mds locked, locking locally");
err = posix_lock_file(file, fl, NULL);
if (err && (CEPH_MDS_OP_SETFILELOCK == op)) {
/* undo! This should only happen if
* the kernel detects local
* deadlock. */
ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
CEPH_LOCK_UNLOCK, 0, fl);
dout("got %d on posix_lock_file, undid lock",
err);
}
}
} else if (err == -ERESTARTSYS) {
dout("undoing lock\n");
ceph_lock_message(CEPH_LOCK_FCNTL, op, file,
CEPH_LOCK_UNLOCK, 0, fl);
}
return err;
}
开发者ID:7799,项目名称:linux,代码行数:55,代码来源:locks.c
示例6: gfs2_lock
static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
struct lm_lockname name =
{ .ln_number = ip->i_no_addr,
.ln_type = LM_TYPE_PLOCK };
if (!(fl->fl_flags & FL_POSIX))
return -ENOLCK;
if (__mandatory_lock(&ip->i_inode))
return -ENOLCK;
if (cmd == F_CANCELLK) {
/* Hack: */
cmd = F_SETLK;
fl->fl_type = F_UNLCK;
}
if (IS_GETLK(cmd))
return gfs2_lm_plock_get(sdp, &name, file, fl);
else if (fl->fl_type == F_UNLCK)
return gfs2_lm_punlock(sdp, &name, file, fl);
else
return gfs2_lm_plock(sdp, &name, file, cmd, fl);
}
static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_file *fp = file->private_data;
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode);
struct gfs2_glock *gl;
unsigned int state;
int flags;
int error = 0;
state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
mutex_lock(&fp->f_fl_mutex);
gl = fl_gh->gh_gl;
if (gl) {
if (fl_gh->gh_state == state)
goto out;
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
gfs2_glock_dq_wait(fl_gh);
gfs2_holder_reinit(state, flags, fl_gh);
} else {
开发者ID:kizukukoto,项目名称:WDN900_GPL,代码行数:50,代码来源:ops_file.c
示例7: gdlm_plock
int gdlm_plock(void *lockspace, struct lm_lockname *name,
struct file *file, int cmd, struct file_lock *fl)
{
struct gdlm_ls *ls = lockspace;
struct plock_op *op;
int rv;
op = kzalloc(sizeof(*op), GFP_KERNEL);
if (!op)
return -ENOMEM;
op->info.optype = GDLM_PLOCK_OP_LOCK;
op->info.pid = fl->fl_pid;
op->info.ex = (fl->fl_type == F_WRLCK);
op->info.wait = IS_SETLKW(cmd);
op->info.fsid = ls->id;
op->info.number = name->ln_number;
op->info.start = fl->fl_start;
op->info.end = fl->fl_end;
op->info.owner = (__u64)(long) fl->fl_owner;
send_op(op);
wait_event(recv_wq, (op->done != 0));
spin_lock(&ops_lock);
if (!list_empty(&op->list)) {
printk(KERN_INFO "plock op on list\n");
list_del(&op->list);
}
spin_unlock(&ops_lock);
rv = op->info.rv;
if (!rv) {
if (posix_lock_file_wait(file, fl) < 0)
log_error("gdlm_plock: vfs lock error %x,%llx",
name->ln_type,
(unsigned long long)name->ln_number);
}
kfree(op);
return rv;
}
开发者ID:xiandaicxsj,项目名称:copyKvm,代码行数:43,代码来源:plock.c
示例8: ceph_flock
int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
{
u8 lock_cmd;
int err;
u8 wait = 0;
if (!(fl->fl_flags & FL_FLOCK))
return -ENOLCK;
/* No mandatory locks */
if (__mandatory_lock(file->f_mapping->host) && fl->fl_type != F_UNLCK)
return -ENOLCK;
dout("ceph_flock, fl_file: %p", fl->fl_file);
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,
file, lock_cmd, wait, fl);
if (!err) {
err = flock_lock_file_wait(file, fl);
if (err) {
ceph_lock_message(CEPH_LOCK_FLOCK,
CEPH_MDS_OP_SETFILELOCK,
file, CEPH_LOCK_UNLOCK, 0, fl);
dout("got %d on flock_lock_file_wait, undid lock", err);
}
} else if (err == -ERESTARTSYS) {
dout("undoing lock\n");
ceph_lock_message(CEPH_LOCK_FLOCK,
CEPH_MDS_OP_SETFILELOCK,
file, CEPH_LOCK_UNLOCK, 0, fl);
}
return err;
}
开发者ID:7799,项目名称:linux,代码行数:42,代码来源:locks.c
示例9: nfs_lock
/*
* Lock a (portion of) a file
*/
int
nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
{
struct inode * inode = filp->f_dentry->d_inode;
int status = 0;
int status2;
dprintk("NFS: nfs_lock(f=%4x/%ld, t=%x, fl=%x, r=%Ld:%Ld)\n",
inode->i_dev, inode->i_ino,
fl->fl_type, fl->fl_flags,
(long long)fl->fl_start, (long long)fl->fl_end);
if (!inode)
return -EINVAL;
/* No mandatory locks over NFS */
if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
return -ENOLCK;
/* Fake OK code if mounted without NLM support */
if (NFS_SERVER(inode)->flags & NFS_MOUNT_NONLM) {
if (IS_GETLK(cmd))
status = LOCK_USE_CLNT;
goto out_ok;
}
/*
* No BSD flocks over NFS allowed.
* Note: we could try to fake a POSIX lock request here by
* using ((u32) filp | 0x80000000) or some such as the pid.
* Not sure whether that would be unique, though, or whether
* that would break in other places.
*/
if (!fl->fl_owner || (fl->fl_flags & (FL_POSIX|FL_BROKEN)) != FL_POSIX)
return -ENOLCK;
/*
* Flush all pending writes before doing anything
* with locks..
*/
status = filemap_fdatasync(inode->i_mapping);
down(&inode->i_sem);
status2 = nfs_wb_all(inode);
if (status2 && !status)
status = status2;
up(&inode->i_sem);
status2 = filemap_fdatawait(inode->i_mapping);
if (status2 && !status)
status = status2;
if (status < 0)
return status;
lock_kernel();
status = nlmclnt_proc(inode, cmd, fl);
unlock_kernel();
if (status < 0)
return status;
status = 0;
/*
* Make sure we clear the cache whenever we try to get the lock.
* This makes locking act as a cache coherency point.
*/
out_ok:
if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
filemap_fdatasync(inode->i_mapping);
down(&inode->i_sem);
nfs_wb_all(inode); /* we may have slept */
up(&inode->i_sem);
filemap_fdatawait(inode->i_mapping);
nfs_zap_caches(inode);
}
return status;
}
开发者ID:iPodLinux,项目名称:linux-2.4.24-ipod,代码行数:78,代码来源:file.c
示例10: gfs2_page_mkwrite
//.........这里部分代码省略.........
* @arg: lease type
* @fl: file lock
*
* We don't currently have a way to enforce a lease across the whole
* cluster; until we do, disable leases (by just returning -EINVAL),
* unless the administrator has requested purely local locking.
*
* Locking: called under i_lock
*
* Returns: errno
*/
static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl)
{
return -EINVAL;
}
/**
* gfs2_lock - acquire/release a posix lock on a file
* @file: the file pointer
* @cmd: either modify or retrieve lock state, possibly wait
* @fl: type and range of lock
*
* Returns: errno
*/
static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
if (!(fl->fl_flags & FL_POSIX))
return -ENOLCK;
if (__mandatory_lock(&ip->i_inode) && fl->fl_type != F_UNLCK)
return -ENOLCK;
if (cmd == F_CANCELLK) {
/* Hack: */
cmd = F_SETLK;
fl->fl_type = F_UNLCK;
}
if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
if (fl->fl_type == F_UNLCK)
posix_lock_file_wait(file, fl);
return -EIO;
}
if (IS_GETLK(cmd))
return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl);
else if (fl->fl_type == F_UNLCK)
return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl);
else
return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl);
}
static int do_flock(struct file *file, int cmd, struct file_lock *fl)
{
struct gfs2_file *fp = file->private_data;
struct gfs2_holder *fl_gh = &fp->f_fl_gh;
struct gfs2_inode *ip = GFS2_I(file_inode(file));
struct gfs2_glock *gl;
unsigned int state;
int flags;
int error = 0;
state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;
flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE;
mutex_lock(&fp->f_fl_mutex);
gl = fl_gh->gh_gl;
if (gl) {
if (fl_gh->gh_state == state)
goto out;
flock_lock_file_wait(file,
&(struct file_lock){.fl_type = F_UNLCK});
gfs2_glock_dq_wait(fl_gh);
gfs2_holder_reinit(state, flags, fl_gh);
} else {
error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr,
&gfs2_flock_glops, CREATE, &gl);
if (error)
goto out;
gfs2_holder_init(gl, state, flags, fl_gh);
gfs2_glock_put(gl);
}
error = gfs2_glock_nq(fl_gh);
if (error) {
gfs2_holder_uninit(fl_gh);
if (error == GLR_TRYFAILED)
error = -EAGAIN;
} else {
error = flock_lock_file_wait(file, fl);
gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
}
out:
mutex_unlock(&fp->f_fl_mutex);
return error;
}
开发者ID:7799,项目名称:linux,代码行数:101,代码来源:file.c
示例11: dlm_posix_lock
int dlm_posix_lock(dlm_lockspace_t *lockspace, u64 number, struct file *file,
int cmd, struct file_lock *fl)
{
struct dlm_ls *ls;
struct plock_op *op;
struct plock_xop *xop;
int rv;
ls = dlm_find_lockspace_local(lockspace);
if (!ls)
return -EINVAL;
xop = kzalloc(sizeof(*xop), GFP_KERNEL);
if (!xop) {
rv = -ENOMEM;
goto out;
}
op = &xop->xop;
op->info.optype = DLM_PLOCK_OP_LOCK;
op->info.pid = fl->fl_pid;
op->info.ex = (fl->fl_type == F_WRLCK);
op->info.wait = IS_SETLKW(cmd);
op->info.fsid = ls->ls_global_id;
op->info.number = number;
op->info.start = fl->fl_start;
op->info.end = fl->fl_end;
if (fl->fl_lmops && fl->fl_lmops->fl_grant) {
/* fl_owner is lockd which doesn't distinguish
processes on the nfs client */
op->info.owner = (__u64) fl->fl_pid;
xop->callback = fl->fl_lmops->fl_grant;
locks_init_lock(&xop->flc);
locks_copy_lock(&xop->flc, fl);
xop->fl = fl;
xop->file = file;
} else {
op->info.owner = (__u64)(long) fl->fl_owner;
xop->callback = NULL;
}
send_op(op);
if (xop->callback == NULL)
wait_event(recv_wq, (op->done != 0));
else {
rv = FILE_LOCK_DEFERRED;
goto out;
}
spin_lock(&ops_lock);
if (!list_empty(&op->list)) {
log_error(ls, "dlm_posix_lock: op on list %llx",
(unsigned long long)number);
list_del(&op->list);
}
spin_unlock(&ops_lock);
rv = op->info.rv;
if (!rv) {
if (posix_lock_file_wait(file, fl) < 0)
log_error(ls, "dlm_posix_lock: vfs lock error %llx",
(unsigned long long)number);
}
kfree(xop);
out:
dlm_put_lockspace(ls);
return rv;
}
开发者ID:325116067,项目名称:semc-qsd8x50,代码行数:71,代码来源:plock.c
示例12: nlmclnt_proc
/*
* This is the main entry point for the NLM client.
*/
int
nlmclnt_proc(struct inode *inode, int cmd, struct file_lock *fl)
{
struct nfs_server *nfssrv = NFS_SERVER(inode);
struct nlm_host *host;
struct nlm_rqst reqst, *call = &reqst;
sigset_t oldset;
unsigned long flags;
int status, proto, vers;
vers = (NFS_PROTO(inode)->version == 3) ? 4 : 1;
if (NFS_PROTO(inode)->version > 3) {
printk(KERN_NOTICE "NFSv4 file locking not implemented!\n");
return -ENOLCK;
}
/* Retrieve transport protocol from NFS client */
proto = NFS_CLIENT(inode)->cl_xprt->prot;
if (!(host = nlmclnt_lookup_host(NFS_ADDR(inode), proto, vers)))
return -ENOLCK;
/* Create RPC client handle if not there, and copy soft
* and intr flags from NFS client. */
if (host->h_rpcclnt == NULL) {
struct rpc_clnt *clnt;
/* Bind an rpc client to this host handle (does not
* perform a portmapper lookup) */
if (!(clnt = nlm_bind_host(host))) {
status = -ENOLCK;
goto done;
}
clnt->cl_softrtry = nfssrv->client->cl_softrtry;
clnt->cl_intr = nfssrv->client->cl_intr;
clnt->cl_chatty = nfssrv->client->cl_chatty;
}
/* Keep the old signal mask */
spin_lock_irqsave(¤t->sighand->siglock, flags);
oldset = current->blocked;
/* If we're cleaning up locks because the process is exiting,
* perform the RPC call asynchronously. */
if ((IS_SETLK(cmd) || IS_SETLKW(cmd))
&& fl->fl_type == F_UNLCK
&& (current->flags & PF_EXITING)) {
sigfillset(¤t->blocked); /* Mask all signals */
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, flags);
call = nlmclnt_alloc_call();
if (!call) {
status = -ENOMEM;
goto out_restore;
}
call->a_flags = RPC_TASK_ASYNC;
} else {
spin_unlock_irqrestore(¤t->sighand->siglock, flags);
memset(call, 0, sizeof(*call));
locks_init_lock(&call->a_args.lock.fl);
locks_init_lock(&call->a_res.lock.fl);
}
call->a_host = host;
/* Set up the argument struct */
nlmclnt_setlockargs(call, fl);
if (IS_SETLK(cmd) || IS_SETLKW(cmd)) {
if (fl->fl_type != F_UNLCK) {
call->a_args.block = IS_SETLKW(cmd) ? 1 : 0;
status = nlmclnt_lock(call, fl);
} else
status = nlmclnt_unlock(call, fl);
} else if (IS_GETLK(cmd))
status = nlmclnt_test(call, fl);
else
status = -EINVAL;
if (status < 0 && (call->a_flags & RPC_TASK_ASYNC))
kfree(call);
out_restore:
spin_lock_irqsave(¤t->sighand->siglock, flags);
current->blocked = oldset;
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, flags);
done:
dprintk("lockd: clnt proc returns %d\n", status);
nlm_release_host(host);
return status;
}
开发者ID:FelipeFernandes1988,项目名称:Alice-1121-Modem,代码行数:96,代码来源:clntproc.c
示例13: v9fs_file_do_lock
static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
{
struct p9_flock flock;
struct p9_fid *fid;
uint8_t status = P9_LOCK_ERROR;
int res = 0;
unsigned char fl_type;
struct v9fs_session_info *v9ses;
fid = filp->private_data;
BUG_ON(fid == NULL);
if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
BUG();
res = locks_lock_file_wait(filp, fl);
if (res < 0)
goto out;
/* convert posix lock to p9 tlock args */
memset(&flock, 0, sizeof(flock));
/* map the lock type */
switch (fl->fl_type) {
case F_RDLCK:
flock.type = P9_LOCK_TYPE_RDLCK;
break;
case F_WRLCK:
flock.type = P9_LOCK_TYPE_WRLCK;
break;
case F_UNLCK:
flock.type = P9_LOCK_TYPE_UNLCK;
break;
}
flock.start = fl->fl_start;
if (fl->fl_end == OFFSET_MAX)
flock.length = 0;
else
flock.length = fl->fl_end - fl->fl_start + 1;
flock.proc_id = fl->fl_pid;
flock.client_id = fid->clnt->name;
if (IS_SETLKW(cmd))
flock.flags = P9_LOCK_FLAGS_BLOCK;
v9ses = v9fs_inode2v9ses(file_inode(filp));
/*
* if its a blocked request and we get P9_LOCK_BLOCKED as the status
* for lock request, keep on trying
*/
for (;;) {
res = p9_client_lock_dotl(fid, &flock, &status);
if (res < 0)
goto out_unlock;
if (status != P9_LOCK_BLOCKED)
break;
if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
break;
if (schedule_timeout_interruptible(v9ses->session_lock_timeout)
!= 0)
break;
/*
* p9_client_lock_dotl overwrites flock.client_id with the
* server message, free and reuse the client name
*/
if (flock.client_id != fid->clnt->name) {
kfree(flock.client_id);
flock.client_id = fid->clnt->name;
}
}
/* map 9p status to VFS status */
switch (status) {
case P9_LOCK_SUCCESS:
res = 0;
break;
case P9_LOCK_BLOCKED:
res = -EAGAIN;
break;
default:
WARN_ONCE(1, "unknown lock status code: %d\n", status);
/* fall through */
case P9_LOCK_ERROR:
case P9_LOCK_GRACE:
res = -ENOLCK;
break;
}
out_unlock:
/*
* incase server returned error for lock request, revert
* it locally
*/
if (res < 0 && fl->fl_type != F_UNLCK) {
fl_type = fl->fl_type;
fl->fl_type = F_UNLCK;
/* Even if this fails we want to return the remote error */
locks_lock_file_wait(filp, fl);
fl->fl_type = fl_type;
}
//.........这里部分代码省略.........
开发者ID:AlexShiLucky,项目名称:linux,代码行数:101,代码来源:vfs_file.c
注:本文中的IS_SETLKW函数示例由纯净天空整理自Github/MSDocs等源码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。 |
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