1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * Copyright (C) 2002 Cluster File Systems, Inc.
6 * This file is part of Lustre, http://www.lustre.org.
8 * Lustre is free software; you can redistribute it and/or
9 * modify it under the terms of version 2 of the GNU General Public
10 * License as published by the Free Software Foundation.
12 * Lustre is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with Lustre; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 #define DEBUG_SUBSYSTEM S_LLITE
24 #include <linux/version.h>
25 #include <linux/lustre_lite.h>
26 #include <linux/lprocfs_status.h>
27 #include <linux/seq_file.h>
28 #include <linux/obd_support.h>
30 #include "llite_internal.h"
32 /* /proc/lustre/llite mount point registration */
33 struct proc_dir_entry *proc_lustre_fs_root;
34 struct file_operations llite_dump_pgcache_fops;
35 struct file_operations ll_ra_stats_fops;
38 int lprocfs_register_mountpoint(struct proc_dir_entry *parent,
39 struct super_block *sb, char *osc, char *mdc)
43 void lprocfs_unregister_mountpoint(struct ll_sb_info *sbi){}
46 long long mnt_instance;
48 static int ll_rd_blksize(char *page, char **start, off_t off, int count,
51 struct super_block *sb = (struct super_block *)data;
52 struct obd_statfs osfs;
56 rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
59 rc = snprintf(page, count, "%u\n", osfs.os_bsize);
65 static int ll_rd_kbytestotal(char *page, char **start, off_t off, int count,
68 struct super_block *sb = (struct super_block *)data;
69 struct obd_statfs osfs;
73 rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
75 __u32 blk_size = osfs.os_bsize >> 10;
76 __u64 result = osfs.os_blocks;
78 while (blk_size >>= 1)
82 rc = snprintf(page, count, LPU64"\n", result);
88 static int ll_rd_kbytesfree(char *page, char **start, off_t off, int count,
91 struct super_block *sb = (struct super_block *)data;
92 struct obd_statfs osfs;
96 rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
98 __u32 blk_size = osfs.os_bsize >> 10;
99 __u64 result = osfs.os_bfree;
101 while (blk_size >>= 1)
105 rc = snprintf(page, count, LPU64"\n", result);
110 static int ll_rd_kbytesavail(char *page, char **start, off_t off, int count,
111 int *eof, void *data)
113 struct super_block *sb = (struct super_block *)data;
114 struct obd_statfs osfs;
118 rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
120 __u32 blk_size = osfs.os_bsize >> 10;
121 __u64 result = osfs.os_bavail;
123 while (blk_size >>= 1)
127 rc = snprintf(page, count, LPU64"\n", result);
132 static int ll_rd_filestotal(char *page, char **start, off_t off, int count,
133 int *eof, void *data)
135 struct super_block *sb = (struct super_block *)data;
136 struct obd_statfs osfs;
140 rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
143 rc = snprintf(page, count, LPU64"\n", osfs.os_files);
148 static int ll_rd_filesfree(char *page, char **start, off_t off, int count,
149 int *eof, void *data)
151 struct super_block *sb = (struct super_block *)data;
152 struct obd_statfs osfs;
156 rc = ll_statfs_internal(sb, &osfs, jiffies - HZ);
159 rc = snprintf(page, count, LPU64"\n", osfs.os_ffree);
165 static int ll_rd_fstype(char *page, char **start, off_t off, int count,
166 int *eof, void *data)
168 struct super_block *sb = (struct super_block*)data;
172 return snprintf(page, count, "%s\n", sb->s_type->name);
175 static int ll_rd_sb_uuid(char *page, char **start, off_t off, int count,
176 int *eof, void *data)
178 struct super_block *sb = (struct super_block *)data;
182 return snprintf(page, count, "%s\n", ll_s2sbi(sb)->ll_sb_uuid.uuid);
185 static int ll_rd_max_readahead_mb(char *page, char **start, off_t off,
186 int count, int *eof, void *data)
188 struct super_block *sb = data;
189 struct ll_sb_info *sbi = ll_s2sbi(sb);
192 spin_lock(&sbi->ll_lock);
193 val = sbi->ll_ra_info.ra_max_pages >> (20 - PAGE_CACHE_SHIFT);
194 spin_unlock(&sbi->ll_lock);
196 return snprintf(page, count, "%u\n", val);
199 static int ll_wr_max_readahead_mb(struct file *file, const char *buffer,
200 unsigned long count, void *data)
202 struct super_block *sb = data;
203 struct ll_sb_info *sbi = ll_s2sbi(sb);
206 rc = lprocfs_write_helper(buffer, count, &val);
210 if (val < 0 || val > (num_physpages >> (20 - PAGE_CACHE_SHIFT - 1))) {
211 CERROR("can't set readahead more than %lu MB\n",
212 num_physpages >> (20 - PAGE_CACHE_SHIFT - 1));
216 spin_lock(&sbi->ll_lock);
217 sbi->ll_ra_info.ra_max_pages = val << (20 - PAGE_CACHE_SHIFT);
218 spin_unlock(&sbi->ll_lock);
223 static int ll_rd_max_cached_mb(char *page, char **start, off_t off,
224 int count, int *eof, void *data)
226 struct super_block *sb = data;
227 struct ll_sb_info *sbi = ll_s2sbi(sb);
230 spin_lock(&sbi->ll_lock);
231 val = sbi->ll_async_page_max >> (20 - PAGE_CACHE_SHIFT);
232 spin_unlock(&sbi->ll_lock);
234 return snprintf(page, count, "%u\n", val);
237 static int ll_wr_max_cached_mb(struct file *file, const char *buffer,
238 unsigned long count, void *data)
240 struct super_block *sb = data;
241 struct ll_sb_info *sbi = ll_s2sbi(sb);
244 rc = lprocfs_write_helper(buffer, count, &val);
248 if (val < 0 || val > (num_physpages >> (20 - PAGE_CACHE_SHIFT))) {
249 CERROR("can't set max cache more than %lu MB\n",
250 num_physpages >> (20 - PAGE_CACHE_SHIFT));
254 spin_lock(&sbi->ll_lock);
255 sbi->ll_async_page_max = val << (20 - PAGE_CACHE_SHIFT);
256 spin_unlock(&sbi->ll_lock);
258 if (sbi->ll_async_page_count >= sbi->ll_async_page_max)
259 llap_shrink_cache(sbi, 0);
264 static int ll_rd_checksum(char *page, char **start, off_t off,
265 int count, int *eof, void *data)
267 struct super_block *sb = data;
268 struct ll_sb_info *sbi = ll_s2sbi(sb);
270 return snprintf(page, count, "%u\n",
271 (sbi->ll_flags & LL_SBI_CHECKSUM) ? 1 : 0);
274 static int ll_wr_checksum(struct file *file, const char *buffer,
275 unsigned long count, void *data)
277 struct super_block *sb = data;
278 struct ll_sb_info *sbi = ll_s2sbi(sb);
281 rc = lprocfs_write_helper(buffer, count, &val);
286 sbi->ll_flags |= LL_SBI_CHECKSUM;
288 sbi->ll_flags &= ~LL_SBI_CHECKSUM;
290 rc = obd_set_info(sbi->ll_osc_exp, strlen("checksum"), "checksum",
293 CWARN("Failed to set OSC checksum flags: %d\n", rc);
298 static struct lprocfs_vars lprocfs_obd_vars[] = {
299 { "uuid", ll_rd_sb_uuid, 0, 0 },
300 //{ "mntpt_path", ll_rd_path, 0, 0 },
301 { "fstype", ll_rd_fstype, 0, 0 },
302 { "blocksize", ll_rd_blksize, 0, 0 },
303 { "kbytestotal", ll_rd_kbytestotal, 0, 0 },
304 { "kbytesfree", ll_rd_kbytesfree, 0, 0 },
305 { "kbytesavail", ll_rd_kbytesavail, 0, 0 },
306 { "filestotal", ll_rd_filestotal, 0, 0 },
307 { "filesfree", ll_rd_filesfree, 0, 0 },
308 //{ "filegroups", lprocfs_rd_filegroups, 0, 0 },
309 { "max_read_ahead_mb", ll_rd_max_readahead_mb,
310 ll_wr_max_readahead_mb, 0 },
311 { "max_cached_mb", ll_rd_max_cached_mb, ll_wr_max_cached_mb, 0 },
312 { "checksum_pages", ll_rd_checksum, ll_wr_checksum, 0 },
316 #define MAX_STRING_SIZE 128
318 struct llite_file_opcode {
322 } llite_opcode_table[LPROC_LL_FILE_OPCODES] = {
324 { LPROC_LL_DIRTY_HITS, LPROCFS_TYPE_REGS, "dirty_pages_hits" },
325 { LPROC_LL_DIRTY_MISSES, LPROCFS_TYPE_REGS, "dirty_pages_misses" },
326 { LPROC_LL_WB_WRITEPAGE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
327 "writeback_from_writepage" },
328 { LPROC_LL_WB_PRESSURE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
329 "writeback_from_pressure" },
330 { LPROC_LL_WB_OK, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
331 "writeback_ok_pages" },
332 { LPROC_LL_WB_FAIL, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
333 "writeback_failed_pages" },
334 { LPROC_LL_READ_BYTES, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_BYTES,
336 { LPROC_LL_WRITE_BYTES, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_BYTES,
338 { LPROC_LL_BRW_READ, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
340 { LPROC_LL_BRW_WRITE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
343 { LPROC_LL_IOCTL, LPROCFS_TYPE_REGS, "ioctl" },
344 { LPROC_LL_OPEN, LPROCFS_TYPE_REGS, "open" },
345 { LPROC_LL_RELEASE, LPROCFS_TYPE_REGS, "close" },
346 { LPROC_LL_MAP, LPROCFS_TYPE_REGS, "mmap" },
347 { LPROC_LL_LLSEEK, LPROCFS_TYPE_REGS, "seek" },
348 { LPROC_LL_FSYNC, LPROCFS_TYPE_REGS, "fsync" },
349 /* inode operation */
350 { LPROC_LL_SETATTR, LPROCFS_TYPE_REGS, "setattr" },
351 { LPROC_LL_TRUNC, LPROCFS_TYPE_REGS, "punch" },
352 #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,5,0))
353 { LPROC_LL_GETATTR, LPROCFS_TYPE_REGS, "getattr" },
355 { LPROC_LL_REVALIDATE, LPROCFS_TYPE_REGS, "getattr" },
357 /* special inode operation */
358 { LPROC_LL_STAFS, LPROCFS_TYPE_REGS, "statfs" },
359 { LPROC_LL_ALLOC_INODE, LPROCFS_TYPE_REGS, "alloc_inode" },
360 { LPROC_LL_DIRECT_READ, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
362 { LPROC_LL_DIRECT_WRITE, LPROCFS_CNTR_AVGMINMAX|LPROCFS_TYPE_PAGES,
367 int lprocfs_register_mountpoint(struct proc_dir_entry *parent,
368 struct super_block *sb, char *osc, char *mdc)
370 struct lprocfs_vars lvars[2];
371 struct ll_sb_info *sbi = ll_s2sbi(sb);
372 struct obd_device *obd;
373 char name[MAX_STRING_SIZE + 1];
375 struct lprocfs_stats *svc_stats = NULL;
376 struct proc_dir_entry *entry;
379 memset(lvars, 0, sizeof(lvars));
381 name[MAX_STRING_SIZE] = '\0';
382 lvars[0].name = name;
384 LASSERT(sbi != NULL);
385 LASSERT(mdc != NULL);
386 LASSERT(osc != NULL);
389 snprintf(name, MAX_STRING_SIZE, "fs%llu", mnt_instance);
392 sbi->ll_proc_root = lprocfs_register(name, parent, NULL, NULL);
393 if (IS_ERR(sbi->ll_proc_root)) {
394 err = PTR_ERR(sbi->ll_proc_root);
395 sbi->ll_proc_root = NULL;
399 entry = create_proc_entry("dump_page_cache", 0444, sbi->ll_proc_root);
401 GOTO(out, err = -ENOMEM);
402 entry->proc_fops = &llite_dump_pgcache_fops;
405 entry = create_proc_entry("read_ahead_stats", 0444, sbi->ll_proc_root);
407 GOTO(out, err = -ENOMEM);
408 entry->proc_fops = &ll_ra_stats_fops;
411 svc_stats = lprocfs_alloc_stats(LPROC_LL_FILE_OPCODES);
412 if (svc_stats == NULL) {
416 /* do counter init */
417 for (id = 0; id < LPROC_LL_FILE_OPCODES; id++) {
418 __u32 type = llite_opcode_table[id].type;
420 if (type & LPROCFS_TYPE_REGS)
423 if (type & LPROCFS_TYPE_BYTES)
426 if (type & LPROCFS_TYPE_PAGES)
430 lprocfs_counter_init(svc_stats, llite_opcode_table[id].opcode,
431 (type & LPROCFS_CNTR_AVGMINMAX),
432 llite_opcode_table[id].opname, ptr);
434 err = lprocfs_register_stats(sbi->ll_proc_root, "stats", svc_stats);
438 sbi->ll_stats = svc_stats;
439 /* need place to keep svc_stats */
441 /* Static configuration info */
442 err = lprocfs_add_vars(sbi->ll_proc_root, lprocfs_obd_vars, sb);
447 obd = class_name2obd(mdc);
449 LASSERT(obd != NULL);
450 LASSERT(obd->obd_type != NULL);
451 LASSERT(obd->obd_type->typ_name != NULL);
453 snprintf(name, MAX_STRING_SIZE, "%s/common_name",
454 obd->obd_type->typ_name);
455 lvars[0].read_fptr = lprocfs_rd_name;
456 err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
460 snprintf(name, MAX_STRING_SIZE, "%s/uuid", obd->obd_type->typ_name);
461 lvars[0].read_fptr = lprocfs_rd_uuid;
462 err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
467 obd = class_name2obd(osc);
469 LASSERT(obd != NULL);
470 LASSERT(obd->obd_type != NULL);
471 LASSERT(obd->obd_type->typ_name != NULL);
473 snprintf(name, MAX_STRING_SIZE, "%s/common_name",
474 obd->obd_type->typ_name);
475 lvars[0].read_fptr = lprocfs_rd_name;
476 err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
480 snprintf(name, MAX_STRING_SIZE, "%s/uuid", obd->obd_type->typ_name);
481 lvars[0].read_fptr = lprocfs_rd_uuid;
482 err = lprocfs_add_vars(sbi->ll_proc_root, lvars, obd);
486 lprocfs_free_stats(svc_stats);
487 if (sbi->ll_proc_root)
488 lprocfs_remove(sbi->ll_proc_root);
493 void lprocfs_unregister_mountpoint(struct ll_sb_info *sbi)
495 if (sbi->ll_proc_root) {
496 struct proc_dir_entry *file_stats =
497 lprocfs_srch(sbi->ll_proc_root, "stats");
500 lprocfs_free_stats(sbi->ll_stats);
501 lprocfs_remove(file_stats);
505 #undef MAX_STRING_SIZE
507 #define seq_page_flag(seq, page, flag, has_flags) do { \
508 if (test_bit(PG_##flag, &(page)->flags)) { \
512 seq_putc(seq, '|'); \
513 seq_puts(seq, #flag); \
517 static void *llite_dump_pgcache_seq_start(struct seq_file *seq, loff_t *pos)
519 struct ll_async_page *dummy_llap = seq->private;
521 if (dummy_llap->llap_magic == 2)
527 static int llite_dump_pgcache_seq_show(struct seq_file *seq, void *v)
529 struct ll_async_page *llap, *dummy_llap = seq->private;
530 struct ll_sb_info *sbi = dummy_llap->llap_cookie;
532 /* 2.4 doesn't seem to have SEQ_START_TOKEN, so we implement
533 * it in our own state */
534 if (dummy_llap->llap_magic == 0) {
535 seq_printf(seq, "gener | llap cookie origin wq du | page "
536 "inode index count [ page flags ]\n");
540 spin_lock(&sbi->ll_lock);
542 llap = llite_pglist_next_llap(sbi, &dummy_llap->llap_pglist_item);
545 struct page *page = llap->llap_page;
547 LASSERTF(llap->llap_origin < LLAP__ORIGIN_MAX, "%u\n",
550 seq_printf(seq, "%5lu | %p %p %s %s %s | %p %p %lu %u [",
552 llap, llap->llap_cookie,
553 llap_origins[llap->llap_origin],
554 llap->llap_write_queued ? "wq" : "- ",
555 llap->llap_defer_uptodate ? "du" : "- ",
556 page, page->mapping->host, page->index,
558 seq_page_flag(seq, page, locked, has_flags);
559 seq_page_flag(seq, page, error, has_flags);
560 seq_page_flag(seq, page, referenced, has_flags);
561 seq_page_flag(seq, page, uptodate, has_flags);
562 seq_page_flag(seq, page, dirty, has_flags);
563 seq_page_flag(seq, page, highmem, has_flags);
565 seq_puts(seq, "-]\n");
567 seq_puts(seq, "]\n");
570 spin_unlock(&sbi->ll_lock);
575 static void *llite_dump_pgcache_seq_next(struct seq_file *seq, void *v,
578 struct ll_async_page *llap, *dummy_llap = seq->private;
579 struct ll_sb_info *sbi = dummy_llap->llap_cookie;
581 /* bail if we just displayed the banner */
582 if (dummy_llap->llap_magic == 0) {
583 dummy_llap->llap_magic = 1;
587 /* we've just displayed the llap that is after us in the list.
588 * we advance to a position beyond it, returning null if there
589 * isn't another llap in the list beyond that new position. */
590 spin_lock(&sbi->ll_lock);
591 llap = llite_pglist_next_llap(sbi, &dummy_llap->llap_pglist_item);
592 list_del_init(&dummy_llap->llap_pglist_item);
594 list_add(&dummy_llap->llap_pglist_item,&llap->llap_pglist_item);
595 llap =llite_pglist_next_llap(sbi,&dummy_llap->llap_pglist_item);
597 spin_unlock(&sbi->ll_lock);
601 dummy_llap->llap_magic = 2;
607 static void llite_dump_pgcache_seq_stop(struct seq_file *seq, void *v)
611 struct seq_operations llite_dump_pgcache_seq_sops = {
612 .start = llite_dump_pgcache_seq_start,
613 .stop = llite_dump_pgcache_seq_stop,
614 .next = llite_dump_pgcache_seq_next,
615 .show = llite_dump_pgcache_seq_show,
618 /* we're displaying llaps in a list_head list. we don't want to hold a lock
619 * while we walk the entire list, and we don't want to have to seek into
620 * the right position in the list as an app advances with many syscalls. we
621 * allocate a dummy llap and hang it off file->private. its position in
622 * the list records where the app is currently displaying. this way our
623 * seq .start and .stop don't actually do anything. .next returns null
624 * when the dummy hits the end of the list which eventually leads to .release
625 * where we tear down. this kind of displaying is super-racey, so we put
626 * a generation counter on the list so the output shows when the list
627 * changes between reads.
629 static int llite_dump_pgcache_seq_open(struct inode *inode, struct file *file)
631 struct proc_dir_entry *dp = PDE(inode);
632 struct ll_async_page *dummy_llap;
633 struct seq_file *seq;
634 struct ll_sb_info *sbi = dp->data;
637 OBD_ALLOC_GFP(dummy_llap, sizeof(*dummy_llap), GFP_KERNEL);
638 if (dummy_llap == NULL)
640 dummy_llap->llap_page = NULL;
641 dummy_llap->llap_cookie = sbi;
642 dummy_llap->llap_magic = 0;
644 rc = seq_open(file, &llite_dump_pgcache_seq_sops);
646 OBD_FREE(dummy_llap, sizeof(*dummy_llap));
649 seq = file->private_data;
650 seq->private = dummy_llap;
652 spin_lock(&sbi->ll_lock);
653 list_add(&dummy_llap->llap_pglist_item, &sbi->ll_pglist);
654 spin_unlock(&sbi->ll_lock);
659 static int llite_dump_pgcache_seq_release(struct inode *inode,
662 struct seq_file *seq = file->private_data;
663 struct ll_async_page *dummy_llap = seq->private;
664 struct ll_sb_info *sbi = dummy_llap->llap_cookie;
666 spin_lock(&sbi->ll_lock);
667 if (!list_empty(&dummy_llap->llap_pglist_item))
668 list_del_init(&dummy_llap->llap_pglist_item);
669 spin_unlock(&sbi->ll_lock);
670 OBD_FREE(dummy_llap, sizeof(*dummy_llap));
672 return seq_release(inode, file);
675 struct file_operations llite_dump_pgcache_fops = {
676 .owner = THIS_MODULE,
677 .open = llite_dump_pgcache_seq_open,
679 .release = llite_dump_pgcache_seq_release,
682 static int ll_ra_stats_seq_show(struct seq_file *seq, void *v)
685 struct ll_sb_info *sbi = seq->private;
686 struct ll_ra_info *ra = &sbi->ll_ra_info;
688 static char *ra_stat_strings[] = {
689 [RA_STAT_HIT] = "hits",
690 [RA_STAT_MISS] = "misses",
691 [RA_STAT_DISTANT_READPAGE] = "readpage not consecutive",
692 [RA_STAT_MISS_IN_WINDOW] = "miss inside window",
693 [RA_STAT_FAILED_MATCH] = "failed lock match",
694 [RA_STAT_DISCARDED] = "read but discarded",
695 [RA_STAT_ZERO_LEN] = "zero length file",
696 [RA_STAT_ZERO_WINDOW] = "zero size window",
697 [RA_STAT_EOF] = "read-ahead to EOF",
698 [RA_STAT_MAX_IN_FLIGHT] = "hit max r-a issue",
701 do_gettimeofday(&now);
703 spin_lock(&sbi->ll_lock);
705 seq_printf(seq, "snapshot_time: %lu.%lu (secs.usecs)\n",
706 now.tv_sec, now.tv_usec);
707 seq_printf(seq, "pending issued pages: %lu\n",
710 for(i = 0; i < _NR_RA_STAT; i++)
711 seq_printf(seq, "%-25s %lu\n", ra_stat_strings[i],
714 spin_unlock(&sbi->ll_lock);
719 static void *ll_ra_stats_seq_start(struct seq_file *p, loff_t *pos)
725 static void *ll_ra_stats_seq_next(struct seq_file *p, void *v, loff_t *pos)
730 static void ll_ra_stats_seq_stop(struct seq_file *p, void *v)
733 struct seq_operations ll_ra_stats_seq_sops = {
734 .start = ll_ra_stats_seq_start,
735 .stop = ll_ra_stats_seq_stop,
736 .next = ll_ra_stats_seq_next,
737 .show = ll_ra_stats_seq_show,
740 static int ll_ra_stats_seq_open(struct inode *inode, struct file *file)
742 struct proc_dir_entry *dp = PDE(inode);
743 struct seq_file *seq;
746 rc = seq_open(file, &ll_ra_stats_seq_sops);
749 seq = file->private_data;
750 seq->private = dp->data;
754 static ssize_t ll_ra_stats_seq_write(struct file *file, const char *buf,
755 size_t len, loff_t *off)
757 struct seq_file *seq = file->private_data;
758 struct ll_sb_info *sbi = seq->private;
759 struct ll_ra_info *ra = &sbi->ll_ra_info;
761 spin_lock(&sbi->ll_lock);
762 memset(ra->ra_stats, 0, sizeof(ra->ra_stats));
763 spin_unlock(&sbi->ll_lock);
768 struct file_operations ll_ra_stats_fops = {
769 .owner = THIS_MODULE,
770 .open = ll_ra_stats_seq_open,
772 .write = ll_ra_stats_seq_write,
774 .release = seq_release,