1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /* -*- mode: c; c-basic-offset: 8; -*-
3*4882a593Smuzhiyun * vim: noexpandtab sw=8 ts=8 sts=0:
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * reservations.c
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Allocation reservations implementation
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * Some code borrowed from fs/ext3/balloc.c and is:
10*4882a593Smuzhiyun *
11*4882a593Smuzhiyun * Copyright (C) 1992, 1993, 1994, 1995
12*4882a593Smuzhiyun * Remy Card (card@masi.ibp.fr)
13*4882a593Smuzhiyun * Laboratoire MASI - Institut Blaise Pascal
14*4882a593Smuzhiyun * Universite Pierre et Marie Curie (Paris VI)
15*4882a593Smuzhiyun *
16*4882a593Smuzhiyun * The rest is copyright (C) 2010 Novell. All rights reserved.
17*4882a593Smuzhiyun */
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun #include <linux/fs.h>
20*4882a593Smuzhiyun #include <linux/types.h>
21*4882a593Smuzhiyun #include <linux/highmem.h>
22*4882a593Smuzhiyun #include <linux/bitops.h>
23*4882a593Smuzhiyun #include <linux/list.h>
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun #include <cluster/masklog.h>
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun #include "ocfs2.h"
28*4882a593Smuzhiyun #include "ocfs2_trace.h"
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun #ifdef CONFIG_OCFS2_DEBUG_FS
31*4882a593Smuzhiyun #define OCFS2_CHECK_RESERVATIONS
32*4882a593Smuzhiyun #endif
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun static DEFINE_SPINLOCK(resv_lock);
35*4882a593Smuzhiyun
ocfs2_dir_resv_allowed(struct ocfs2_super * osb)36*4882a593Smuzhiyun int ocfs2_dir_resv_allowed(struct ocfs2_super *osb)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun return (osb->osb_resv_level && osb->osb_dir_resv_level);
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun
ocfs2_resv_window_bits(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv)41*4882a593Smuzhiyun static unsigned int ocfs2_resv_window_bits(struct ocfs2_reservation_map *resmap,
42*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun struct ocfs2_super *osb = resmap->m_osb;
45*4882a593Smuzhiyun unsigned int bits;
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun if (!(resv->r_flags & OCFS2_RESV_FLAG_DIR)) {
48*4882a593Smuzhiyun /* 8, 16, 32, 64, 128, 256, 512, 1024 */
49*4882a593Smuzhiyun bits = 4 << osb->osb_resv_level;
50*4882a593Smuzhiyun } else {
51*4882a593Smuzhiyun bits = 4 << osb->osb_dir_resv_level;
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun return bits;
54*4882a593Smuzhiyun }
55*4882a593Smuzhiyun
ocfs2_resv_end(struct ocfs2_alloc_reservation * resv)56*4882a593Smuzhiyun static inline unsigned int ocfs2_resv_end(struct ocfs2_alloc_reservation *resv)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun if (resv->r_len)
59*4882a593Smuzhiyun return resv->r_start + resv->r_len - 1;
60*4882a593Smuzhiyun return resv->r_start;
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
ocfs2_resv_empty(struct ocfs2_alloc_reservation * resv)63*4882a593Smuzhiyun static inline int ocfs2_resv_empty(struct ocfs2_alloc_reservation *resv)
64*4882a593Smuzhiyun {
65*4882a593Smuzhiyun return !!(resv->r_len == 0);
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun
ocfs2_resmap_disabled(struct ocfs2_reservation_map * resmap)68*4882a593Smuzhiyun static inline int ocfs2_resmap_disabled(struct ocfs2_reservation_map *resmap)
69*4882a593Smuzhiyun {
70*4882a593Smuzhiyun if (resmap->m_osb->osb_resv_level == 0)
71*4882a593Smuzhiyun return 1;
72*4882a593Smuzhiyun return 0;
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun
ocfs2_dump_resv(struct ocfs2_reservation_map * resmap)75*4882a593Smuzhiyun static void ocfs2_dump_resv(struct ocfs2_reservation_map *resmap)
76*4882a593Smuzhiyun {
77*4882a593Smuzhiyun struct ocfs2_super *osb = resmap->m_osb;
78*4882a593Smuzhiyun struct rb_node *node;
79*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv;
80*4882a593Smuzhiyun int i = 0;
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun mlog(ML_NOTICE, "Dumping resmap for device %s. Bitmap length: %u\n",
83*4882a593Smuzhiyun osb->dev_str, resmap->m_bitmap_len);
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun node = rb_first(&resmap->m_reservations);
86*4882a593Smuzhiyun while (node) {
87*4882a593Smuzhiyun resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node);
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun mlog(ML_NOTICE, "start: %u\tend: %u\tlen: %u\tlast_start: %u"
90*4882a593Smuzhiyun "\tlast_len: %u\n", resv->r_start,
91*4882a593Smuzhiyun ocfs2_resv_end(resv), resv->r_len, resv->r_last_start,
92*4882a593Smuzhiyun resv->r_last_len);
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun node = rb_next(node);
95*4882a593Smuzhiyun i++;
96*4882a593Smuzhiyun }
97*4882a593Smuzhiyun
98*4882a593Smuzhiyun mlog(ML_NOTICE, "%d reservations found. LRU follows\n", i);
99*4882a593Smuzhiyun
100*4882a593Smuzhiyun i = 0;
101*4882a593Smuzhiyun list_for_each_entry(resv, &resmap->m_lru, r_lru) {
102*4882a593Smuzhiyun mlog(ML_NOTICE, "LRU(%d) start: %u\tend: %u\tlen: %u\t"
103*4882a593Smuzhiyun "last_start: %u\tlast_len: %u\n", i, resv->r_start,
104*4882a593Smuzhiyun ocfs2_resv_end(resv), resv->r_len, resv->r_last_start,
105*4882a593Smuzhiyun resv->r_last_len);
106*4882a593Smuzhiyun
107*4882a593Smuzhiyun i++;
108*4882a593Smuzhiyun }
109*4882a593Smuzhiyun }
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun #ifdef OCFS2_CHECK_RESERVATIONS
ocfs2_validate_resmap_bits(struct ocfs2_reservation_map * resmap,int i,struct ocfs2_alloc_reservation * resv)112*4882a593Smuzhiyun static int ocfs2_validate_resmap_bits(struct ocfs2_reservation_map *resmap,
113*4882a593Smuzhiyun int i,
114*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv)
115*4882a593Smuzhiyun {
116*4882a593Smuzhiyun char *disk_bitmap = resmap->m_disk_bitmap;
117*4882a593Smuzhiyun unsigned int start = resv->r_start;
118*4882a593Smuzhiyun unsigned int end = ocfs2_resv_end(resv);
119*4882a593Smuzhiyun
120*4882a593Smuzhiyun while (start <= end) {
121*4882a593Smuzhiyun if (ocfs2_test_bit(start, disk_bitmap)) {
122*4882a593Smuzhiyun mlog(ML_ERROR,
123*4882a593Smuzhiyun "reservation %d covers an allocated area "
124*4882a593Smuzhiyun "starting at bit %u!\n", i, start);
125*4882a593Smuzhiyun return 1;
126*4882a593Smuzhiyun }
127*4882a593Smuzhiyun
128*4882a593Smuzhiyun start++;
129*4882a593Smuzhiyun }
130*4882a593Smuzhiyun return 0;
131*4882a593Smuzhiyun }
132*4882a593Smuzhiyun
ocfs2_check_resmap(struct ocfs2_reservation_map * resmap)133*4882a593Smuzhiyun static void ocfs2_check_resmap(struct ocfs2_reservation_map *resmap)
134*4882a593Smuzhiyun {
135*4882a593Smuzhiyun unsigned int off = 0;
136*4882a593Smuzhiyun int i = 0;
137*4882a593Smuzhiyun struct rb_node *node;
138*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv;
139*4882a593Smuzhiyun
140*4882a593Smuzhiyun node = rb_first(&resmap->m_reservations);
141*4882a593Smuzhiyun while (node) {
142*4882a593Smuzhiyun resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node);
143*4882a593Smuzhiyun
144*4882a593Smuzhiyun if (i > 0 && resv->r_start <= off) {
145*4882a593Smuzhiyun mlog(ML_ERROR, "reservation %d has bad start off!\n",
146*4882a593Smuzhiyun i);
147*4882a593Smuzhiyun goto bad;
148*4882a593Smuzhiyun }
149*4882a593Smuzhiyun
150*4882a593Smuzhiyun if (resv->r_len == 0) {
151*4882a593Smuzhiyun mlog(ML_ERROR, "reservation %d has no length!\n",
152*4882a593Smuzhiyun i);
153*4882a593Smuzhiyun goto bad;
154*4882a593Smuzhiyun }
155*4882a593Smuzhiyun
156*4882a593Smuzhiyun if (resv->r_start > ocfs2_resv_end(resv)) {
157*4882a593Smuzhiyun mlog(ML_ERROR, "reservation %d has invalid range!\n",
158*4882a593Smuzhiyun i);
159*4882a593Smuzhiyun goto bad;
160*4882a593Smuzhiyun }
161*4882a593Smuzhiyun
162*4882a593Smuzhiyun if (ocfs2_resv_end(resv) >= resmap->m_bitmap_len) {
163*4882a593Smuzhiyun mlog(ML_ERROR, "reservation %d extends past bitmap!\n",
164*4882a593Smuzhiyun i);
165*4882a593Smuzhiyun goto bad;
166*4882a593Smuzhiyun }
167*4882a593Smuzhiyun
168*4882a593Smuzhiyun if (ocfs2_validate_resmap_bits(resmap, i, resv))
169*4882a593Smuzhiyun goto bad;
170*4882a593Smuzhiyun
171*4882a593Smuzhiyun off = ocfs2_resv_end(resv);
172*4882a593Smuzhiyun node = rb_next(node);
173*4882a593Smuzhiyun
174*4882a593Smuzhiyun i++;
175*4882a593Smuzhiyun }
176*4882a593Smuzhiyun return;
177*4882a593Smuzhiyun
178*4882a593Smuzhiyun bad:
179*4882a593Smuzhiyun ocfs2_dump_resv(resmap);
180*4882a593Smuzhiyun BUG();
181*4882a593Smuzhiyun }
182*4882a593Smuzhiyun #else
ocfs2_check_resmap(struct ocfs2_reservation_map * resmap)183*4882a593Smuzhiyun static inline void ocfs2_check_resmap(struct ocfs2_reservation_map *resmap)
184*4882a593Smuzhiyun {
185*4882a593Smuzhiyun
186*4882a593Smuzhiyun }
187*4882a593Smuzhiyun #endif
188*4882a593Smuzhiyun
ocfs2_resv_init_once(struct ocfs2_alloc_reservation * resv)189*4882a593Smuzhiyun void ocfs2_resv_init_once(struct ocfs2_alloc_reservation *resv)
190*4882a593Smuzhiyun {
191*4882a593Smuzhiyun memset(resv, 0, sizeof(*resv));
192*4882a593Smuzhiyun INIT_LIST_HEAD(&resv->r_lru);
193*4882a593Smuzhiyun }
194*4882a593Smuzhiyun
ocfs2_resv_set_type(struct ocfs2_alloc_reservation * resv,unsigned int flags)195*4882a593Smuzhiyun void ocfs2_resv_set_type(struct ocfs2_alloc_reservation *resv,
196*4882a593Smuzhiyun unsigned int flags)
197*4882a593Smuzhiyun {
198*4882a593Smuzhiyun BUG_ON(flags & ~OCFS2_RESV_TYPES);
199*4882a593Smuzhiyun
200*4882a593Smuzhiyun resv->r_flags |= flags;
201*4882a593Smuzhiyun }
202*4882a593Smuzhiyun
ocfs2_resmap_init(struct ocfs2_super * osb,struct ocfs2_reservation_map * resmap)203*4882a593Smuzhiyun int ocfs2_resmap_init(struct ocfs2_super *osb,
204*4882a593Smuzhiyun struct ocfs2_reservation_map *resmap)
205*4882a593Smuzhiyun {
206*4882a593Smuzhiyun memset(resmap, 0, sizeof(*resmap));
207*4882a593Smuzhiyun
208*4882a593Smuzhiyun resmap->m_osb = osb;
209*4882a593Smuzhiyun resmap->m_reservations = RB_ROOT;
210*4882a593Smuzhiyun /* m_bitmap_len is initialized to zero by the above memset. */
211*4882a593Smuzhiyun INIT_LIST_HEAD(&resmap->m_lru);
212*4882a593Smuzhiyun
213*4882a593Smuzhiyun return 0;
214*4882a593Smuzhiyun }
215*4882a593Smuzhiyun
ocfs2_resv_mark_lru(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv)216*4882a593Smuzhiyun static void ocfs2_resv_mark_lru(struct ocfs2_reservation_map *resmap,
217*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv)
218*4882a593Smuzhiyun {
219*4882a593Smuzhiyun assert_spin_locked(&resv_lock);
220*4882a593Smuzhiyun
221*4882a593Smuzhiyun if (!list_empty(&resv->r_lru))
222*4882a593Smuzhiyun list_del_init(&resv->r_lru);
223*4882a593Smuzhiyun
224*4882a593Smuzhiyun list_add_tail(&resv->r_lru, &resmap->m_lru);
225*4882a593Smuzhiyun }
226*4882a593Smuzhiyun
__ocfs2_resv_trunc(struct ocfs2_alloc_reservation * resv)227*4882a593Smuzhiyun static void __ocfs2_resv_trunc(struct ocfs2_alloc_reservation *resv)
228*4882a593Smuzhiyun {
229*4882a593Smuzhiyun resv->r_len = 0;
230*4882a593Smuzhiyun resv->r_start = 0;
231*4882a593Smuzhiyun }
232*4882a593Smuzhiyun
ocfs2_resv_remove(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv)233*4882a593Smuzhiyun static void ocfs2_resv_remove(struct ocfs2_reservation_map *resmap,
234*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv)
235*4882a593Smuzhiyun {
236*4882a593Smuzhiyun if (resv->r_flags & OCFS2_RESV_FLAG_INUSE) {
237*4882a593Smuzhiyun list_del_init(&resv->r_lru);
238*4882a593Smuzhiyun rb_erase(&resv->r_node, &resmap->m_reservations);
239*4882a593Smuzhiyun resv->r_flags &= ~OCFS2_RESV_FLAG_INUSE;
240*4882a593Smuzhiyun }
241*4882a593Smuzhiyun }
242*4882a593Smuzhiyun
__ocfs2_resv_discard(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv)243*4882a593Smuzhiyun static void __ocfs2_resv_discard(struct ocfs2_reservation_map *resmap,
244*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv)
245*4882a593Smuzhiyun {
246*4882a593Smuzhiyun assert_spin_locked(&resv_lock);
247*4882a593Smuzhiyun
248*4882a593Smuzhiyun __ocfs2_resv_trunc(resv);
249*4882a593Smuzhiyun /*
250*4882a593Smuzhiyun * last_len and last_start no longer make sense if
251*4882a593Smuzhiyun * we're changing the range of our allocations.
252*4882a593Smuzhiyun */
253*4882a593Smuzhiyun resv->r_last_len = resv->r_last_start = 0;
254*4882a593Smuzhiyun
255*4882a593Smuzhiyun ocfs2_resv_remove(resmap, resv);
256*4882a593Smuzhiyun }
257*4882a593Smuzhiyun
258*4882a593Smuzhiyun /* does nothing if 'resv' is null */
ocfs2_resv_discard(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv)259*4882a593Smuzhiyun void ocfs2_resv_discard(struct ocfs2_reservation_map *resmap,
260*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv)
261*4882a593Smuzhiyun {
262*4882a593Smuzhiyun if (resv) {
263*4882a593Smuzhiyun spin_lock(&resv_lock);
264*4882a593Smuzhiyun __ocfs2_resv_discard(resmap, resv);
265*4882a593Smuzhiyun spin_unlock(&resv_lock);
266*4882a593Smuzhiyun }
267*4882a593Smuzhiyun }
268*4882a593Smuzhiyun
ocfs2_resmap_clear_all_resv(struct ocfs2_reservation_map * resmap)269*4882a593Smuzhiyun static void ocfs2_resmap_clear_all_resv(struct ocfs2_reservation_map *resmap)
270*4882a593Smuzhiyun {
271*4882a593Smuzhiyun struct rb_node *node;
272*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv;
273*4882a593Smuzhiyun
274*4882a593Smuzhiyun assert_spin_locked(&resv_lock);
275*4882a593Smuzhiyun
276*4882a593Smuzhiyun while ((node = rb_last(&resmap->m_reservations)) != NULL) {
277*4882a593Smuzhiyun resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node);
278*4882a593Smuzhiyun
279*4882a593Smuzhiyun __ocfs2_resv_discard(resmap, resv);
280*4882a593Smuzhiyun }
281*4882a593Smuzhiyun }
282*4882a593Smuzhiyun
ocfs2_resmap_restart(struct ocfs2_reservation_map * resmap,unsigned int clen,char * disk_bitmap)283*4882a593Smuzhiyun void ocfs2_resmap_restart(struct ocfs2_reservation_map *resmap,
284*4882a593Smuzhiyun unsigned int clen, char *disk_bitmap)
285*4882a593Smuzhiyun {
286*4882a593Smuzhiyun if (ocfs2_resmap_disabled(resmap))
287*4882a593Smuzhiyun return;
288*4882a593Smuzhiyun
289*4882a593Smuzhiyun spin_lock(&resv_lock);
290*4882a593Smuzhiyun
291*4882a593Smuzhiyun ocfs2_resmap_clear_all_resv(resmap);
292*4882a593Smuzhiyun resmap->m_bitmap_len = clen;
293*4882a593Smuzhiyun resmap->m_disk_bitmap = disk_bitmap;
294*4882a593Smuzhiyun
295*4882a593Smuzhiyun spin_unlock(&resv_lock);
296*4882a593Smuzhiyun }
297*4882a593Smuzhiyun
ocfs2_resmap_uninit(struct ocfs2_reservation_map * resmap)298*4882a593Smuzhiyun void ocfs2_resmap_uninit(struct ocfs2_reservation_map *resmap)
299*4882a593Smuzhiyun {
300*4882a593Smuzhiyun /* Does nothing for now. Keep this around for API symmetry */
301*4882a593Smuzhiyun }
302*4882a593Smuzhiyun
ocfs2_resv_insert(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * new)303*4882a593Smuzhiyun static void ocfs2_resv_insert(struct ocfs2_reservation_map *resmap,
304*4882a593Smuzhiyun struct ocfs2_alloc_reservation *new)
305*4882a593Smuzhiyun {
306*4882a593Smuzhiyun struct rb_root *root = &resmap->m_reservations;
307*4882a593Smuzhiyun struct rb_node *parent = NULL;
308*4882a593Smuzhiyun struct rb_node **p = &root->rb_node;
309*4882a593Smuzhiyun struct ocfs2_alloc_reservation *tmp;
310*4882a593Smuzhiyun
311*4882a593Smuzhiyun assert_spin_locked(&resv_lock);
312*4882a593Smuzhiyun
313*4882a593Smuzhiyun trace_ocfs2_resv_insert(new->r_start, new->r_len);
314*4882a593Smuzhiyun
315*4882a593Smuzhiyun while (*p) {
316*4882a593Smuzhiyun parent = *p;
317*4882a593Smuzhiyun
318*4882a593Smuzhiyun tmp = rb_entry(parent, struct ocfs2_alloc_reservation, r_node);
319*4882a593Smuzhiyun
320*4882a593Smuzhiyun if (new->r_start < tmp->r_start) {
321*4882a593Smuzhiyun p = &(*p)->rb_left;
322*4882a593Smuzhiyun
323*4882a593Smuzhiyun /*
324*4882a593Smuzhiyun * This is a good place to check for
325*4882a593Smuzhiyun * overlapping reservations.
326*4882a593Smuzhiyun */
327*4882a593Smuzhiyun BUG_ON(ocfs2_resv_end(new) >= tmp->r_start);
328*4882a593Smuzhiyun } else if (new->r_start > ocfs2_resv_end(tmp)) {
329*4882a593Smuzhiyun p = &(*p)->rb_right;
330*4882a593Smuzhiyun } else {
331*4882a593Smuzhiyun /* This should never happen! */
332*4882a593Smuzhiyun mlog(ML_ERROR, "Duplicate reservation window!\n");
333*4882a593Smuzhiyun BUG();
334*4882a593Smuzhiyun }
335*4882a593Smuzhiyun }
336*4882a593Smuzhiyun
337*4882a593Smuzhiyun rb_link_node(&new->r_node, parent, p);
338*4882a593Smuzhiyun rb_insert_color(&new->r_node, root);
339*4882a593Smuzhiyun new->r_flags |= OCFS2_RESV_FLAG_INUSE;
340*4882a593Smuzhiyun
341*4882a593Smuzhiyun ocfs2_resv_mark_lru(resmap, new);
342*4882a593Smuzhiyun
343*4882a593Smuzhiyun ocfs2_check_resmap(resmap);
344*4882a593Smuzhiyun }
345*4882a593Smuzhiyun
346*4882a593Smuzhiyun /**
347*4882a593Smuzhiyun * ocfs2_find_resv_lhs() - find the window which contains goal
348*4882a593Smuzhiyun * @resmap: reservation map to search
349*4882a593Smuzhiyun * @goal: which bit to search for
350*4882a593Smuzhiyun *
351*4882a593Smuzhiyun * If a window containing that goal is not found, we return the window
352*4882a593Smuzhiyun * which comes before goal. Returns NULL on empty rbtree or no window
353*4882a593Smuzhiyun * before goal.
354*4882a593Smuzhiyun */
355*4882a593Smuzhiyun static struct ocfs2_alloc_reservation *
ocfs2_find_resv_lhs(struct ocfs2_reservation_map * resmap,unsigned int goal)356*4882a593Smuzhiyun ocfs2_find_resv_lhs(struct ocfs2_reservation_map *resmap, unsigned int goal)
357*4882a593Smuzhiyun {
358*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv = NULL;
359*4882a593Smuzhiyun struct ocfs2_alloc_reservation *prev_resv = NULL;
360*4882a593Smuzhiyun struct rb_node *node = resmap->m_reservations.rb_node;
361*4882a593Smuzhiyun
362*4882a593Smuzhiyun assert_spin_locked(&resv_lock);
363*4882a593Smuzhiyun
364*4882a593Smuzhiyun if (!node)
365*4882a593Smuzhiyun return NULL;
366*4882a593Smuzhiyun
367*4882a593Smuzhiyun node = rb_first(&resmap->m_reservations);
368*4882a593Smuzhiyun while (node) {
369*4882a593Smuzhiyun resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node);
370*4882a593Smuzhiyun
371*4882a593Smuzhiyun if (resv->r_start <= goal && ocfs2_resv_end(resv) >= goal)
372*4882a593Smuzhiyun break;
373*4882a593Smuzhiyun
374*4882a593Smuzhiyun /* Check if we overshot the reservation just before goal? */
375*4882a593Smuzhiyun if (resv->r_start > goal) {
376*4882a593Smuzhiyun resv = prev_resv;
377*4882a593Smuzhiyun break;
378*4882a593Smuzhiyun }
379*4882a593Smuzhiyun
380*4882a593Smuzhiyun prev_resv = resv;
381*4882a593Smuzhiyun node = rb_next(node);
382*4882a593Smuzhiyun }
383*4882a593Smuzhiyun
384*4882a593Smuzhiyun return resv;
385*4882a593Smuzhiyun }
386*4882a593Smuzhiyun
387*4882a593Smuzhiyun /*
388*4882a593Smuzhiyun * We are given a range within the bitmap, which corresponds to a gap
389*4882a593Smuzhiyun * inside the reservations tree (search_start, search_len). The range
390*4882a593Smuzhiyun * can be anything from the whole bitmap, to a gap between
391*4882a593Smuzhiyun * reservations.
392*4882a593Smuzhiyun *
393*4882a593Smuzhiyun * The start value of *rstart is insignificant.
394*4882a593Smuzhiyun *
395*4882a593Smuzhiyun * This function searches the bitmap range starting at search_start
396*4882a593Smuzhiyun * with length search_len for a set of contiguous free bits. We try
397*4882a593Smuzhiyun * to find up to 'wanted' bits, but can sometimes return less.
398*4882a593Smuzhiyun *
399*4882a593Smuzhiyun * Returns the length of allocation, 0 if no free bits are found.
400*4882a593Smuzhiyun *
401*4882a593Smuzhiyun * *cstart and *clen will also be populated with the result.
402*4882a593Smuzhiyun */
ocfs2_resmap_find_free_bits(struct ocfs2_reservation_map * resmap,unsigned int wanted,unsigned int search_start,unsigned int search_len,unsigned int * rstart,unsigned int * rlen)403*4882a593Smuzhiyun static int ocfs2_resmap_find_free_bits(struct ocfs2_reservation_map *resmap,
404*4882a593Smuzhiyun unsigned int wanted,
405*4882a593Smuzhiyun unsigned int search_start,
406*4882a593Smuzhiyun unsigned int search_len,
407*4882a593Smuzhiyun unsigned int *rstart,
408*4882a593Smuzhiyun unsigned int *rlen)
409*4882a593Smuzhiyun {
410*4882a593Smuzhiyun void *bitmap = resmap->m_disk_bitmap;
411*4882a593Smuzhiyun unsigned int best_start, best_len = 0;
412*4882a593Smuzhiyun int offset, start, found;
413*4882a593Smuzhiyun
414*4882a593Smuzhiyun trace_ocfs2_resmap_find_free_bits_begin(search_start, search_len,
415*4882a593Smuzhiyun wanted, resmap->m_bitmap_len);
416*4882a593Smuzhiyun
417*4882a593Smuzhiyun found = best_start = best_len = 0;
418*4882a593Smuzhiyun
419*4882a593Smuzhiyun start = search_start;
420*4882a593Smuzhiyun while ((offset = ocfs2_find_next_zero_bit(bitmap, resmap->m_bitmap_len,
421*4882a593Smuzhiyun start)) != -1) {
422*4882a593Smuzhiyun /* Search reached end of the region */
423*4882a593Smuzhiyun if (offset >= (search_start + search_len))
424*4882a593Smuzhiyun break;
425*4882a593Smuzhiyun
426*4882a593Smuzhiyun if (offset == start) {
427*4882a593Smuzhiyun /* we found a zero */
428*4882a593Smuzhiyun found++;
429*4882a593Smuzhiyun /* move start to the next bit to test */
430*4882a593Smuzhiyun start++;
431*4882a593Smuzhiyun } else {
432*4882a593Smuzhiyun /* got a zero after some ones */
433*4882a593Smuzhiyun found = 1;
434*4882a593Smuzhiyun start = offset + 1;
435*4882a593Smuzhiyun }
436*4882a593Smuzhiyun if (found > best_len) {
437*4882a593Smuzhiyun best_len = found;
438*4882a593Smuzhiyun best_start = start - found;
439*4882a593Smuzhiyun }
440*4882a593Smuzhiyun
441*4882a593Smuzhiyun if (found >= wanted)
442*4882a593Smuzhiyun break;
443*4882a593Smuzhiyun }
444*4882a593Smuzhiyun
445*4882a593Smuzhiyun if (best_len == 0)
446*4882a593Smuzhiyun return 0;
447*4882a593Smuzhiyun
448*4882a593Smuzhiyun if (best_len >= wanted)
449*4882a593Smuzhiyun best_len = wanted;
450*4882a593Smuzhiyun
451*4882a593Smuzhiyun *rlen = best_len;
452*4882a593Smuzhiyun *rstart = best_start;
453*4882a593Smuzhiyun
454*4882a593Smuzhiyun trace_ocfs2_resmap_find_free_bits_end(best_start, best_len);
455*4882a593Smuzhiyun
456*4882a593Smuzhiyun return *rlen;
457*4882a593Smuzhiyun }
458*4882a593Smuzhiyun
__ocfs2_resv_find_window(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv,unsigned int goal,unsigned int wanted)459*4882a593Smuzhiyun static void __ocfs2_resv_find_window(struct ocfs2_reservation_map *resmap,
460*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv,
461*4882a593Smuzhiyun unsigned int goal, unsigned int wanted)
462*4882a593Smuzhiyun {
463*4882a593Smuzhiyun struct rb_root *root = &resmap->m_reservations;
464*4882a593Smuzhiyun unsigned int gap_start, gap_end, gap_len;
465*4882a593Smuzhiyun struct ocfs2_alloc_reservation *prev_resv, *next_resv;
466*4882a593Smuzhiyun struct rb_node *prev, *next;
467*4882a593Smuzhiyun unsigned int cstart, clen;
468*4882a593Smuzhiyun unsigned int best_start = 0, best_len = 0;
469*4882a593Smuzhiyun
470*4882a593Smuzhiyun /*
471*4882a593Smuzhiyun * Nasty cases to consider:
472*4882a593Smuzhiyun *
473*4882a593Smuzhiyun * - rbtree is empty
474*4882a593Smuzhiyun * - our window should be first in all reservations
475*4882a593Smuzhiyun * - our window should be last in all reservations
476*4882a593Smuzhiyun * - need to make sure we don't go past end of bitmap
477*4882a593Smuzhiyun */
478*4882a593Smuzhiyun trace_ocfs2_resv_find_window_begin(resv->r_start, ocfs2_resv_end(resv),
479*4882a593Smuzhiyun goal, wanted, RB_EMPTY_ROOT(root));
480*4882a593Smuzhiyun
481*4882a593Smuzhiyun assert_spin_locked(&resv_lock);
482*4882a593Smuzhiyun
483*4882a593Smuzhiyun if (RB_EMPTY_ROOT(root)) {
484*4882a593Smuzhiyun /*
485*4882a593Smuzhiyun * Easiest case - empty tree. We can just take
486*4882a593Smuzhiyun * whatever window of free bits we want.
487*4882a593Smuzhiyun */
488*4882a593Smuzhiyun clen = ocfs2_resmap_find_free_bits(resmap, wanted, goal,
489*4882a593Smuzhiyun resmap->m_bitmap_len - goal,
490*4882a593Smuzhiyun &cstart, &clen);
491*4882a593Smuzhiyun
492*4882a593Smuzhiyun /*
493*4882a593Smuzhiyun * This should never happen - the local alloc window
494*4882a593Smuzhiyun * will always have free bits when we're called.
495*4882a593Smuzhiyun */
496*4882a593Smuzhiyun BUG_ON(goal == 0 && clen == 0);
497*4882a593Smuzhiyun
498*4882a593Smuzhiyun if (clen == 0)
499*4882a593Smuzhiyun return;
500*4882a593Smuzhiyun
501*4882a593Smuzhiyun resv->r_start = cstart;
502*4882a593Smuzhiyun resv->r_len = clen;
503*4882a593Smuzhiyun
504*4882a593Smuzhiyun ocfs2_resv_insert(resmap, resv);
505*4882a593Smuzhiyun return;
506*4882a593Smuzhiyun }
507*4882a593Smuzhiyun
508*4882a593Smuzhiyun prev_resv = ocfs2_find_resv_lhs(resmap, goal);
509*4882a593Smuzhiyun
510*4882a593Smuzhiyun if (prev_resv == NULL) {
511*4882a593Smuzhiyun /*
512*4882a593Smuzhiyun * A NULL here means that the search code couldn't
513*4882a593Smuzhiyun * find a window that starts before goal.
514*4882a593Smuzhiyun *
515*4882a593Smuzhiyun * However, we can take the first window after goal,
516*4882a593Smuzhiyun * which is also by definition, the leftmost window in
517*4882a593Smuzhiyun * the entire tree. If we can find free bits in the
518*4882a593Smuzhiyun * gap between goal and the LHS window, then the
519*4882a593Smuzhiyun * reservation can safely be placed there.
520*4882a593Smuzhiyun *
521*4882a593Smuzhiyun * Otherwise we fall back to a linear search, checking
522*4882a593Smuzhiyun * the gaps in between windows for a place to
523*4882a593Smuzhiyun * allocate.
524*4882a593Smuzhiyun */
525*4882a593Smuzhiyun
526*4882a593Smuzhiyun next = rb_first(root);
527*4882a593Smuzhiyun next_resv = rb_entry(next, struct ocfs2_alloc_reservation,
528*4882a593Smuzhiyun r_node);
529*4882a593Smuzhiyun
530*4882a593Smuzhiyun /*
531*4882a593Smuzhiyun * The search should never return such a window. (see
532*4882a593Smuzhiyun * comment above
533*4882a593Smuzhiyun */
534*4882a593Smuzhiyun if (next_resv->r_start <= goal) {
535*4882a593Smuzhiyun mlog(ML_ERROR, "goal: %u next_resv: start %u len %u\n",
536*4882a593Smuzhiyun goal, next_resv->r_start, next_resv->r_len);
537*4882a593Smuzhiyun ocfs2_dump_resv(resmap);
538*4882a593Smuzhiyun BUG();
539*4882a593Smuzhiyun }
540*4882a593Smuzhiyun
541*4882a593Smuzhiyun clen = ocfs2_resmap_find_free_bits(resmap, wanted, goal,
542*4882a593Smuzhiyun next_resv->r_start - goal,
543*4882a593Smuzhiyun &cstart, &clen);
544*4882a593Smuzhiyun if (clen) {
545*4882a593Smuzhiyun best_len = clen;
546*4882a593Smuzhiyun best_start = cstart;
547*4882a593Smuzhiyun if (best_len == wanted)
548*4882a593Smuzhiyun goto out_insert;
549*4882a593Smuzhiyun }
550*4882a593Smuzhiyun
551*4882a593Smuzhiyun prev_resv = next_resv;
552*4882a593Smuzhiyun next_resv = NULL;
553*4882a593Smuzhiyun }
554*4882a593Smuzhiyun
555*4882a593Smuzhiyun trace_ocfs2_resv_find_window_prev(prev_resv->r_start,
556*4882a593Smuzhiyun ocfs2_resv_end(prev_resv));
557*4882a593Smuzhiyun
558*4882a593Smuzhiyun prev = &prev_resv->r_node;
559*4882a593Smuzhiyun
560*4882a593Smuzhiyun /* Now we do a linear search for a window, starting at 'prev_rsv' */
561*4882a593Smuzhiyun while (1) {
562*4882a593Smuzhiyun next = rb_next(prev);
563*4882a593Smuzhiyun if (next) {
564*4882a593Smuzhiyun next_resv = rb_entry(next,
565*4882a593Smuzhiyun struct ocfs2_alloc_reservation,
566*4882a593Smuzhiyun r_node);
567*4882a593Smuzhiyun
568*4882a593Smuzhiyun gap_start = ocfs2_resv_end(prev_resv) + 1;
569*4882a593Smuzhiyun gap_end = next_resv->r_start - 1;
570*4882a593Smuzhiyun gap_len = gap_end - gap_start + 1;
571*4882a593Smuzhiyun } else {
572*4882a593Smuzhiyun /*
573*4882a593Smuzhiyun * We're at the rightmost edge of the
574*4882a593Smuzhiyun * tree. See if a reservation between this
575*4882a593Smuzhiyun * window and the end of the bitmap will work.
576*4882a593Smuzhiyun */
577*4882a593Smuzhiyun gap_start = ocfs2_resv_end(prev_resv) + 1;
578*4882a593Smuzhiyun gap_len = resmap->m_bitmap_len - gap_start;
579*4882a593Smuzhiyun gap_end = resmap->m_bitmap_len - 1;
580*4882a593Smuzhiyun }
581*4882a593Smuzhiyun
582*4882a593Smuzhiyun trace_ocfs2_resv_find_window_next(next ? next_resv->r_start: -1,
583*4882a593Smuzhiyun next ? ocfs2_resv_end(next_resv) : -1);
584*4882a593Smuzhiyun /*
585*4882a593Smuzhiyun * No need to check this gap if we have already found
586*4882a593Smuzhiyun * a larger region of free bits.
587*4882a593Smuzhiyun */
588*4882a593Smuzhiyun if (gap_len <= best_len)
589*4882a593Smuzhiyun goto next_resv;
590*4882a593Smuzhiyun
591*4882a593Smuzhiyun clen = ocfs2_resmap_find_free_bits(resmap, wanted, gap_start,
592*4882a593Smuzhiyun gap_len, &cstart, &clen);
593*4882a593Smuzhiyun if (clen == wanted) {
594*4882a593Smuzhiyun best_len = clen;
595*4882a593Smuzhiyun best_start = cstart;
596*4882a593Smuzhiyun goto out_insert;
597*4882a593Smuzhiyun } else if (clen > best_len) {
598*4882a593Smuzhiyun best_len = clen;
599*4882a593Smuzhiyun best_start = cstart;
600*4882a593Smuzhiyun }
601*4882a593Smuzhiyun
602*4882a593Smuzhiyun next_resv:
603*4882a593Smuzhiyun if (!next)
604*4882a593Smuzhiyun break;
605*4882a593Smuzhiyun
606*4882a593Smuzhiyun prev = next;
607*4882a593Smuzhiyun prev_resv = rb_entry(prev, struct ocfs2_alloc_reservation,
608*4882a593Smuzhiyun r_node);
609*4882a593Smuzhiyun }
610*4882a593Smuzhiyun
611*4882a593Smuzhiyun out_insert:
612*4882a593Smuzhiyun if (best_len) {
613*4882a593Smuzhiyun resv->r_start = best_start;
614*4882a593Smuzhiyun resv->r_len = best_len;
615*4882a593Smuzhiyun ocfs2_resv_insert(resmap, resv);
616*4882a593Smuzhiyun }
617*4882a593Smuzhiyun }
618*4882a593Smuzhiyun
ocfs2_cannibalize_resv(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv,unsigned int wanted)619*4882a593Smuzhiyun static void ocfs2_cannibalize_resv(struct ocfs2_reservation_map *resmap,
620*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv,
621*4882a593Smuzhiyun unsigned int wanted)
622*4882a593Smuzhiyun {
623*4882a593Smuzhiyun struct ocfs2_alloc_reservation *lru_resv;
624*4882a593Smuzhiyun int tmpwindow = !!(resv->r_flags & OCFS2_RESV_FLAG_TMP);
625*4882a593Smuzhiyun unsigned int min_bits;
626*4882a593Smuzhiyun
627*4882a593Smuzhiyun if (!tmpwindow)
628*4882a593Smuzhiyun min_bits = ocfs2_resv_window_bits(resmap, resv) >> 1;
629*4882a593Smuzhiyun else
630*4882a593Smuzhiyun min_bits = wanted; /* We at know the temp window will use all
631*4882a593Smuzhiyun * of these bits */
632*4882a593Smuzhiyun
633*4882a593Smuzhiyun /*
634*4882a593Smuzhiyun * Take the first reservation off the LRU as our 'target'. We
635*4882a593Smuzhiyun * don't try to be smart about it. There might be a case for
636*4882a593Smuzhiyun * searching based on size but I don't have enough data to be
637*4882a593Smuzhiyun * sure. --Mark (3/16/2010)
638*4882a593Smuzhiyun */
639*4882a593Smuzhiyun lru_resv = list_first_entry(&resmap->m_lru,
640*4882a593Smuzhiyun struct ocfs2_alloc_reservation, r_lru);
641*4882a593Smuzhiyun
642*4882a593Smuzhiyun trace_ocfs2_cannibalize_resv_begin(lru_resv->r_start,
643*4882a593Smuzhiyun lru_resv->r_len,
644*4882a593Smuzhiyun ocfs2_resv_end(lru_resv));
645*4882a593Smuzhiyun
646*4882a593Smuzhiyun /*
647*4882a593Smuzhiyun * Cannibalize (some or all) of the target reservation and
648*4882a593Smuzhiyun * feed it to the current window.
649*4882a593Smuzhiyun */
650*4882a593Smuzhiyun if (lru_resv->r_len <= min_bits) {
651*4882a593Smuzhiyun /*
652*4882a593Smuzhiyun * Discard completely if size is less than or equal to a
653*4882a593Smuzhiyun * reasonable threshold - 50% of window bits for non temporary
654*4882a593Smuzhiyun * windows.
655*4882a593Smuzhiyun */
656*4882a593Smuzhiyun resv->r_start = lru_resv->r_start;
657*4882a593Smuzhiyun resv->r_len = lru_resv->r_len;
658*4882a593Smuzhiyun
659*4882a593Smuzhiyun __ocfs2_resv_discard(resmap, lru_resv);
660*4882a593Smuzhiyun } else {
661*4882a593Smuzhiyun unsigned int shrink;
662*4882a593Smuzhiyun if (tmpwindow)
663*4882a593Smuzhiyun shrink = min_bits;
664*4882a593Smuzhiyun else
665*4882a593Smuzhiyun shrink = lru_resv->r_len / 2;
666*4882a593Smuzhiyun
667*4882a593Smuzhiyun lru_resv->r_len -= shrink;
668*4882a593Smuzhiyun
669*4882a593Smuzhiyun resv->r_start = ocfs2_resv_end(lru_resv) + 1;
670*4882a593Smuzhiyun resv->r_len = shrink;
671*4882a593Smuzhiyun }
672*4882a593Smuzhiyun
673*4882a593Smuzhiyun trace_ocfs2_cannibalize_resv_end(resv->r_start, ocfs2_resv_end(resv),
674*4882a593Smuzhiyun resv->r_len, resv->r_last_start,
675*4882a593Smuzhiyun resv->r_last_len);
676*4882a593Smuzhiyun
677*4882a593Smuzhiyun ocfs2_resv_insert(resmap, resv);
678*4882a593Smuzhiyun }
679*4882a593Smuzhiyun
ocfs2_resv_find_window(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv,unsigned int wanted)680*4882a593Smuzhiyun static void ocfs2_resv_find_window(struct ocfs2_reservation_map *resmap,
681*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv,
682*4882a593Smuzhiyun unsigned int wanted)
683*4882a593Smuzhiyun {
684*4882a593Smuzhiyun unsigned int goal = 0;
685*4882a593Smuzhiyun
686*4882a593Smuzhiyun BUG_ON(!ocfs2_resv_empty(resv));
687*4882a593Smuzhiyun
688*4882a593Smuzhiyun /*
689*4882a593Smuzhiyun * Begin by trying to get a window as close to the previous
690*4882a593Smuzhiyun * one as possible. Using the most recent allocation as a
691*4882a593Smuzhiyun * start goal makes sense.
692*4882a593Smuzhiyun */
693*4882a593Smuzhiyun if (resv->r_last_len) {
694*4882a593Smuzhiyun goal = resv->r_last_start + resv->r_last_len;
695*4882a593Smuzhiyun if (goal >= resmap->m_bitmap_len)
696*4882a593Smuzhiyun goal = 0;
697*4882a593Smuzhiyun }
698*4882a593Smuzhiyun
699*4882a593Smuzhiyun __ocfs2_resv_find_window(resmap, resv, goal, wanted);
700*4882a593Smuzhiyun
701*4882a593Smuzhiyun /* Search from last alloc didn't work, try once more from beginning. */
702*4882a593Smuzhiyun if (ocfs2_resv_empty(resv) && goal != 0)
703*4882a593Smuzhiyun __ocfs2_resv_find_window(resmap, resv, 0, wanted);
704*4882a593Smuzhiyun
705*4882a593Smuzhiyun if (ocfs2_resv_empty(resv)) {
706*4882a593Smuzhiyun /*
707*4882a593Smuzhiyun * Still empty? Pull oldest one off the LRU, remove it from
708*4882a593Smuzhiyun * tree, put this one in it's place.
709*4882a593Smuzhiyun */
710*4882a593Smuzhiyun ocfs2_cannibalize_resv(resmap, resv, wanted);
711*4882a593Smuzhiyun }
712*4882a593Smuzhiyun
713*4882a593Smuzhiyun BUG_ON(ocfs2_resv_empty(resv));
714*4882a593Smuzhiyun }
715*4882a593Smuzhiyun
ocfs2_resmap_resv_bits(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv,int * cstart,int * clen)716*4882a593Smuzhiyun int ocfs2_resmap_resv_bits(struct ocfs2_reservation_map *resmap,
717*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv,
718*4882a593Smuzhiyun int *cstart, int *clen)
719*4882a593Smuzhiyun {
720*4882a593Smuzhiyun if (resv == NULL || ocfs2_resmap_disabled(resmap))
721*4882a593Smuzhiyun return -ENOSPC;
722*4882a593Smuzhiyun
723*4882a593Smuzhiyun spin_lock(&resv_lock);
724*4882a593Smuzhiyun
725*4882a593Smuzhiyun if (ocfs2_resv_empty(resv)) {
726*4882a593Smuzhiyun /*
727*4882a593Smuzhiyun * We don't want to over-allocate for temporary
728*4882a593Smuzhiyun * windows. Otherwise, we run the risk of fragmenting the
729*4882a593Smuzhiyun * allocation space.
730*4882a593Smuzhiyun */
731*4882a593Smuzhiyun unsigned int wanted = ocfs2_resv_window_bits(resmap, resv);
732*4882a593Smuzhiyun
733*4882a593Smuzhiyun if ((resv->r_flags & OCFS2_RESV_FLAG_TMP) || wanted < *clen)
734*4882a593Smuzhiyun wanted = *clen;
735*4882a593Smuzhiyun
736*4882a593Smuzhiyun /*
737*4882a593Smuzhiyun * Try to get a window here. If it works, we must fall
738*4882a593Smuzhiyun * through and test the bitmap . This avoids some
739*4882a593Smuzhiyun * ping-ponging of windows due to non-reserved space
740*4882a593Smuzhiyun * being allocation before we initialize a window for
741*4882a593Smuzhiyun * that inode.
742*4882a593Smuzhiyun */
743*4882a593Smuzhiyun ocfs2_resv_find_window(resmap, resv, wanted);
744*4882a593Smuzhiyun trace_ocfs2_resmap_resv_bits(resv->r_start, resv->r_len);
745*4882a593Smuzhiyun }
746*4882a593Smuzhiyun
747*4882a593Smuzhiyun BUG_ON(ocfs2_resv_empty(resv));
748*4882a593Smuzhiyun
749*4882a593Smuzhiyun *cstart = resv->r_start;
750*4882a593Smuzhiyun *clen = resv->r_len;
751*4882a593Smuzhiyun
752*4882a593Smuzhiyun spin_unlock(&resv_lock);
753*4882a593Smuzhiyun return 0;
754*4882a593Smuzhiyun }
755*4882a593Smuzhiyun
756*4882a593Smuzhiyun static void
ocfs2_adjust_resv_from_alloc(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv,unsigned int start,unsigned int end)757*4882a593Smuzhiyun ocfs2_adjust_resv_from_alloc(struct ocfs2_reservation_map *resmap,
758*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv,
759*4882a593Smuzhiyun unsigned int start, unsigned int end)
760*4882a593Smuzhiyun {
761*4882a593Smuzhiyun unsigned int rhs = 0;
762*4882a593Smuzhiyun unsigned int old_end = ocfs2_resv_end(resv);
763*4882a593Smuzhiyun
764*4882a593Smuzhiyun BUG_ON(start != resv->r_start || old_end < end);
765*4882a593Smuzhiyun
766*4882a593Smuzhiyun /*
767*4882a593Smuzhiyun * Completely used? We can remove it then.
768*4882a593Smuzhiyun */
769*4882a593Smuzhiyun if (old_end == end) {
770*4882a593Smuzhiyun __ocfs2_resv_discard(resmap, resv);
771*4882a593Smuzhiyun return;
772*4882a593Smuzhiyun }
773*4882a593Smuzhiyun
774*4882a593Smuzhiyun rhs = old_end - end;
775*4882a593Smuzhiyun
776*4882a593Smuzhiyun /*
777*4882a593Smuzhiyun * This should have been trapped above.
778*4882a593Smuzhiyun */
779*4882a593Smuzhiyun BUG_ON(rhs == 0);
780*4882a593Smuzhiyun
781*4882a593Smuzhiyun resv->r_start = end + 1;
782*4882a593Smuzhiyun resv->r_len = old_end - resv->r_start + 1;
783*4882a593Smuzhiyun }
784*4882a593Smuzhiyun
ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map * resmap,struct ocfs2_alloc_reservation * resv,u32 cstart,u32 clen)785*4882a593Smuzhiyun void ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map *resmap,
786*4882a593Smuzhiyun struct ocfs2_alloc_reservation *resv,
787*4882a593Smuzhiyun u32 cstart, u32 clen)
788*4882a593Smuzhiyun {
789*4882a593Smuzhiyun unsigned int cend = cstart + clen - 1;
790*4882a593Smuzhiyun
791*4882a593Smuzhiyun if (resmap == NULL || ocfs2_resmap_disabled(resmap))
792*4882a593Smuzhiyun return;
793*4882a593Smuzhiyun
794*4882a593Smuzhiyun if (resv == NULL)
795*4882a593Smuzhiyun return;
796*4882a593Smuzhiyun
797*4882a593Smuzhiyun BUG_ON(cstart != resv->r_start);
798*4882a593Smuzhiyun
799*4882a593Smuzhiyun spin_lock(&resv_lock);
800*4882a593Smuzhiyun
801*4882a593Smuzhiyun trace_ocfs2_resmap_claimed_bits_begin(cstart, cend, clen, resv->r_start,
802*4882a593Smuzhiyun ocfs2_resv_end(resv), resv->r_len,
803*4882a593Smuzhiyun resv->r_last_start,
804*4882a593Smuzhiyun resv->r_last_len);
805*4882a593Smuzhiyun
806*4882a593Smuzhiyun BUG_ON(cstart < resv->r_start);
807*4882a593Smuzhiyun BUG_ON(cstart > ocfs2_resv_end(resv));
808*4882a593Smuzhiyun BUG_ON(cend > ocfs2_resv_end(resv));
809*4882a593Smuzhiyun
810*4882a593Smuzhiyun ocfs2_adjust_resv_from_alloc(resmap, resv, cstart, cend);
811*4882a593Smuzhiyun resv->r_last_start = cstart;
812*4882a593Smuzhiyun resv->r_last_len = clen;
813*4882a593Smuzhiyun
814*4882a593Smuzhiyun /*
815*4882a593Smuzhiyun * May have been discarded above from
816*4882a593Smuzhiyun * ocfs2_adjust_resv_from_alloc().
817*4882a593Smuzhiyun */
818*4882a593Smuzhiyun if (!ocfs2_resv_empty(resv))
819*4882a593Smuzhiyun ocfs2_resv_mark_lru(resmap, resv);
820*4882a593Smuzhiyun
821*4882a593Smuzhiyun trace_ocfs2_resmap_claimed_bits_end(resv->r_start, ocfs2_resv_end(resv),
822*4882a593Smuzhiyun resv->r_len, resv->r_last_start,
823*4882a593Smuzhiyun resv->r_last_len);
824*4882a593Smuzhiyun
825*4882a593Smuzhiyun ocfs2_check_resmap(resmap);
826*4882a593Smuzhiyun
827*4882a593Smuzhiyun spin_unlock(&resv_lock);
828*4882a593Smuzhiyun }
829