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36 * Implementation of cl_lock for LOV layer.
38 * Author: Nikita Danilov <nikita.danilov@sun.com>
41 #define DEBUG_SUBSYSTEM S_LOV
43 #include "lov_cl_internal.h"
49 /*****************************************************************************
51 * Lov lock operations.
55 static struct lov_sublock_env *lov_sublock_env_get(const struct lu_env *env,
56 const struct cl_lock *parent,
57 struct lov_lock_sub *lls)
59 struct lov_sublock_env *subenv;
60 struct lov_io *lio = lov_env_io(env);
61 struct cl_io *io = lio->lis_cl.cis_io;
62 struct lov_io_sub *sub;
64 subenv = &lov_env_session(env)->ls_subenv;
67 * FIXME: We tend to use the subio's env & io to call the sublock
68 * lock operations because osc lock sometimes stores some control
69 * variables in thread's IO infomation(Now only lockless information).
70 * However, if the lock's host(object) is different from the object
71 * for current IO, we have no way to get the subenv and subio because
72 * they are not initialized at all. As a temp fix, in this case,
73 * we still borrow the parent's env to call sublock operations.
75 if (!io || !cl_object_same(io->ci_obj, parent->cll_descr.cld_obj)) {
76 subenv->lse_env = env;
78 subenv->lse_sub = NULL;
80 sub = lov_sub_get(env, lio, lls->sub_stripe);
82 subenv->lse_env = sub->sub_env;
83 subenv->lse_io = sub->sub_io;
84 subenv->lse_sub = sub;
92 static void lov_sublock_env_put(struct lov_sublock_env *subenv)
94 if (subenv && subenv->lse_sub)
95 lov_sub_put(subenv->lse_sub);
98 static int lov_sublock_init(const struct lu_env *env,
99 const struct cl_lock *parent,
100 struct lov_lock_sub *lls)
102 struct lov_sublock_env *subenv;
106 subenv = lov_sublock_env_get(env, parent, lls);
107 if (!IS_ERR(subenv)) {
108 result = cl_lock_init(subenv->lse_env, &lls->sub_lock,
110 lov_sublock_env_put(subenv);
113 result = PTR_ERR(subenv);
119 * Creates sub-locks for a given lov_lock for the first time.
121 * Goes through all sub-objects of top-object, and creates sub-locks on every
122 * sub-object intersecting with top-lock extent. This is complicated by the
123 * fact that top-lock (that is being created) can be accessed concurrently
124 * through already created sub-locks (possibly shared with other top-locks).
126 static struct lov_lock *lov_lock_sub_init(const struct lu_env *env,
127 const struct cl_object *obj,
128 struct cl_lock *lock)
138 struct lov_object *loo = cl2lov(obj);
139 struct lov_layout_raid0 *r0 = lov_r0(loo);
140 struct lov_lock *lovlck;
144 file_start = cl_offset(lov2cl(loo), lock->cll_descr.cld_start);
145 file_end = cl_offset(lov2cl(loo), lock->cll_descr.cld_end + 1) - 1;
147 for (i = 0, nr = 0; i < r0->lo_nr; i++) {
149 * XXX for wide striping smarter algorithm is desirable,
150 * breaking out of the loop, early.
152 if (likely(r0->lo_sub[i] != NULL) && /* spare layout */
153 lov_stripe_intersects(loo->lo_lsm, i,
154 file_start, file_end, &start, &end))
159 OBD_ALLOC_LARGE(lovlck, offsetof(struct lov_lock, lls_sub[nr]));
161 RETURN(ERR_PTR(-ENOMEM));
164 for (i = 0, nr = 0; i < r0->lo_nr; ++i) {
165 if (likely(r0->lo_sub[i] != NULL) &&
166 lov_stripe_intersects(loo->lo_lsm, i,
167 file_start, file_end, &start, &end)) {
168 struct lov_lock_sub *lls = &lovlck->lls_sub[nr];
169 struct cl_lock_descr *descr;
171 descr = &lls->sub_lock.cll_descr;
173 LASSERT(descr->cld_obj == NULL);
174 descr->cld_obj = lovsub2cl(r0->lo_sub[i]);
175 descr->cld_start = cl_index(descr->cld_obj, start);
176 descr->cld_end = cl_index(descr->cld_obj, end);
177 descr->cld_mode = lock->cll_descr.cld_mode;
178 descr->cld_gid = lock->cll_descr.cld_gid;
179 descr->cld_enq_flags = lock->cll_descr.cld_enq_flags;
183 /* initialize sub lock */
184 result = lov_sublock_init(env, lock, lls);
188 lls->sub_initialized = 1;
192 LASSERT(ergo(result == 0, nr == lovlck->lls_nr));
195 for (i = 0; i < nr; ++i) {
196 if (!lovlck->lls_sub[i].sub_initialized)
199 cl_lock_fini(env, &lovlck->lls_sub[i].sub_lock);
202 OBD_FREE_LARGE(lovlck,
203 offsetof(struct lov_lock, lls_sub[nr]));
204 lovlck = ERR_PTR(result);
210 static void lov_lock_fini(const struct lu_env *env,
211 struct cl_lock_slice *slice)
213 struct lov_lock *lovlck;
217 lovlck = cl2lov_lock(slice);
218 for (i = 0; i < lovlck->lls_nr; ++i) {
219 LASSERT(!lovlck->lls_sub[i].sub_is_enqueued);
220 if (lovlck->lls_sub[i].sub_initialized)
221 cl_lock_fini(env, &lovlck->lls_sub[i].sub_lock);
223 OBD_FREE_LARGE(lovlck,
224 offsetof(struct lov_lock, lls_sub[lovlck->lls_nr]));
229 * Implementation of cl_lock_operations::clo_enqueue() for lov layer. This
230 * function is rather subtle, as it enqueues top-lock (i.e., advances top-lock
231 * state machine from CLS_QUEUING to CLS_ENQUEUED states) by juggling sub-lock
232 * state machines in the face of sub-locks sharing (by multiple top-locks),
233 * and concurrent sub-lock cancellations.
235 static int lov_lock_enqueue(const struct lu_env *env,
236 const struct cl_lock_slice *slice,
237 struct cl_io *io, struct cl_sync_io *anchor)
239 struct cl_lock *lock = slice->cls_lock;
240 struct lov_lock *lovlck = cl2lov_lock(slice);
246 for (i = 0; i < lovlck->lls_nr; ++i) {
247 struct lov_lock_sub *lls = &lovlck->lls_sub[i];
248 struct lov_sublock_env *subenv;
250 subenv = lov_sublock_env_get(env, lock, lls);
251 if (IS_ERR(subenv)) {
252 rc = PTR_ERR(subenv);
256 rc = cl_lock_enqueue(subenv->lse_env, subenv->lse_io,
257 &lls->sub_lock, anchor);
258 lov_sublock_env_put(subenv);
262 lls->sub_is_enqueued = 1;
267 static void lov_lock_cancel(const struct lu_env *env,
268 const struct cl_lock_slice *slice)
270 struct cl_lock *lock = slice->cls_lock;
271 struct lov_lock *lovlck = cl2lov_lock(slice);
276 for (i = 0; i < lovlck->lls_nr; ++i) {
277 struct lov_lock_sub *lls = &lovlck->lls_sub[i];
278 struct cl_lock *sublock = &lls->sub_lock;
279 struct lov_sublock_env *subenv;
281 if (!lls->sub_is_enqueued)
284 lls->sub_is_enqueued = 0;
285 subenv = lov_sublock_env_get(env, lock, lls);
286 if (!IS_ERR(subenv)) {
287 cl_lock_cancel(subenv->lse_env, sublock);
288 lov_sublock_env_put(subenv);
290 CL_LOCK_DEBUG(D_ERROR, env, slice->cls_lock,
291 "lov_lock_cancel fails with %ld.\n",
297 static int lov_lock_print(const struct lu_env *env, void *cookie,
298 lu_printer_t p, const struct cl_lock_slice *slice)
300 struct lov_lock *lck = cl2lov_lock(slice);
303 (*p)(env, cookie, "%d\n", lck->lls_nr);
304 for (i = 0; i < lck->lls_nr; ++i) {
305 struct lov_lock_sub *sub;
307 sub = &lck->lls_sub[i];
308 (*p)(env, cookie, " %d %x: ", i, sub->sub_is_enqueued);
309 cl_lock_print(env, cookie, p, &sub->sub_lock);
314 static const struct cl_lock_operations lov_lock_ops = {
315 .clo_fini = lov_lock_fini,
316 .clo_enqueue = lov_lock_enqueue,
317 .clo_cancel = lov_lock_cancel,
318 .clo_print = lov_lock_print
321 int lov_lock_init_raid0(const struct lu_env *env, struct cl_object *obj,
322 struct cl_lock *lock, const struct cl_io *io)
324 struct lov_lock *lck;
328 lck = lov_lock_sub_init(env, obj, lock);
330 cl_lock_slice_add(lock, &lck->lls_cl, obj, &lov_lock_ops);
332 result = PTR_ERR(lck);
336 static void lov_empty_lock_fini(const struct lu_env *env,
337 struct cl_lock_slice *slice)
339 struct lov_lock *lck = cl2lov_lock(slice);
340 OBD_SLAB_FREE_PTR(lck, lov_lock_kmem);
343 static int lov_empty_lock_print(const struct lu_env *env, void *cookie,
344 lu_printer_t p, const struct cl_lock_slice *slice)
346 (*p)(env, cookie, "empty\n");
350 /* XXX: more methods will be added later. */
351 static const struct cl_lock_operations lov_empty_lock_ops = {
352 .clo_fini = lov_empty_lock_fini,
353 .clo_print = lov_empty_lock_print
356 int lov_lock_init_empty(const struct lu_env *env, struct cl_object *obj,
357 struct cl_lock *lock, const struct cl_io *io)
359 struct lov_lock *lck;
360 int result = -ENOMEM;
363 OBD_SLAB_ALLOC_PTR_GFP(lck, lov_lock_kmem, GFP_NOFS);
365 cl_lock_slice_add(lock, &lck->lls_cl, obj, &lov_empty_lock_ops);