int cl_glimpse_lock(const struct lu_env *env, struct cl_io *io,
struct inode *inode, struct cl_object *clob, int agl)
{
const struct lu_fid *fid = lu_object_fid(&clob->co_lu);
struct cl_lock *lock = vvp_env_lock(env);
struct cl_lock_descr *descr = &lock->cll_descr;
int result = 0;
CDEBUG(D_DLMTRACE, "Glimpsing inode " DFID "\n", PFID(fid));
/* NOTE: this looks like DLM lock request, but it may
* not be one. Due to CEF_ASYNC flag (translated
* to LDLM_FL_HAS_INTENT by osc), this is
* glimpse request, that won't revoke any
* conflicting DLM locks held. Instead,
* ll_glimpse_callback() will be called on each
* client holding a DLM lock against this file,
* and resulting size will be returned for each
* stripe. DLM lock on [0, EOF] is acquired only
* if there were no conflicting locks. If there
* were conflicting locks, enqueuing or waiting
* fails with -ENAVAIL, but valid inode
* attributes are returned anyway.
*/
*descr = whole_file;
descr->cld_obj = clob;
descr->cld_mode = CLM_READ;
descr->cld_enq_flags = CEF_ASYNC | CEF_MUST;
if (agl)
descr->cld_enq_flags |= CEF_AGL;
/*
* CEF_ASYNC is used because glimpse sub-locks cannot
* deadlock (because they never conflict with other
* locks) and, hence, can be enqueued out-of-order.
*
* CEF_MUST protects glimpse lock from conversion into
* a lockless mode.
*/
result = cl_lock_request(env, io, lock);
if (result < 0)
return result;
if (!agl) {
ll_merge_attr(env, inode);
if (i_size_read(inode) > 0 && !inode->i_blocks) {
/*
* LU-417: Add dirty pages block count
* lest i_blocks reports 0, some "cp" or
* "tar" may think it's a completely
* sparse file and skip it.
*/
inode->i_blocks = dirty_cnt(inode);
}
}
cl_lock_release(env, lock);
return result;
}
int cl_get_grouplock(struct cl_object *obj, unsigned long gid, int nonblock,
struct ll_grouplock *lg)
{
struct lu_env *env;
struct cl_io *io;
struct cl_lock *lock;
struct cl_lock_descr *descr;
__u32 enqflags;
__u16 refcheck;
int rc;
env = cl_env_get(&refcheck);
if (IS_ERR(env))
return PTR_ERR(env);
io = vvp_env_thread_io(env);
io->ci_obj = obj;
rc = cl_io_init(env, io, CIT_MISC, io->ci_obj);
if (rc != 0) {
cl_io_fini(env, io);
cl_env_put(env, &refcheck);
/* Does not make sense to take GL for released layout */
if (rc > 0)
rc = -ENOTSUPP;
return rc;
}
lock = vvp_env_lock(env);
descr = &lock->cll_descr;
descr->cld_obj = obj;
descr->cld_start = 0;
descr->cld_end = CL_PAGE_EOF;
descr->cld_gid = gid;
descr->cld_mode = CLM_GROUP;
enqflags = CEF_MUST | (nonblock ? CEF_NONBLOCK : 0);
descr->cld_enq_flags = enqflags;
rc = cl_lock_request(env, io, lock);
if (rc < 0) {
cl_io_fini(env, io);
cl_env_put(env, &refcheck);
return rc;
}
lg->lg_env = env;
lg->lg_io = io;
lg->lg_lock = lock;
lg->lg_gid = gid;
return 0;
}
