+++ /dev/null
-/*
- * OBDFS Super operations - also used for Lustre file system
- *
- *
- * This code is issued under the GNU General Public License.
- * See the file COPYING in this distribution
- *
- * Copyright (C) 1991, 1992 Linus Torvalds
- * Copryright (C) 1999 Stelias Computing Inc. <braam@stelias.com>
- * Copryright (C) 1999 Seagate Technology Inc.
- *
- */
-#define __NO_VERSION__
-#include <linux/fs.h>
-#include <linux/locks.h>
-#include <linux/swap.h>
-
-#include <linux/obd_support.h>
-#include <linux/obd_class.h>
-#include <linux/obdfs.h>
-
-
-/* XXX temporary until the real function is available from kernel
- * XXX set this to memory size in pages for max page cache size
- */
-#define nr_free_buffer_pages() 32768
-
-/* Defines for page buf daemon */
-struct pupd_prm {
- int nfract; /* Percentage of buffer cache dirty to
- activate bdflush */
- int ndirty; /* Maximum number of dirty blocks to write out per
- wake-cycle */
- int nrefill; /* Number of clean buffers to try to obtain
- each time we call refill */
- int nref_dirt; /* Dirty buffer threshold for activating bdflush
- when trying to refill buffers. */
- int interval; /* jiffies delay between pupdate flushes */
- int age_buffer; /* Time for normal buffer to age before we flush it */
- int age_super; /* Time for superblock to age before we flush it */
-};
-
-
-static struct pupdated {
- int active;
- wait_queue_head_t waitq;
- struct timer_list timer;
- struct pupd_prm parms;
-} pupdated = {
- active: -1,
- parms: {40, 1024, 64, 256, 1*HZ, 30*HZ, 5*HZ }
-};
-
-
-/* Called with the superblock list lock held */
-static int obdfs_enqueue_pages(struct inode *inode, struct obdo **obdo,
- int nr_slots, struct page **pages, char **bufs,
- obd_size *counts, obd_off *offsets,
- obd_flag *flag, unsigned long check_time)
-{
- struct list_head *page_list = obdfs_iplist(inode);
- struct list_head *tmp;
- int num = 0;
-
- ENTRY;
-
- tmp = page_list;
- /* Traverse list in reverse order, so we do FIFO, not LIFO order */
- while ( (tmp = tmp->prev) != page_list && num < nr_slots ) {
- struct obdfs_pgrq *req;
- struct page *page;
-
- req = list_entry(tmp, struct obdfs_pgrq, rq_plist);
- page = req->rq_page;
-
-
- if (req->rq_jiffies > check_time)
- break; /* pages are in chronological order */
-
- /* Only allocate the obdo if we will actually do I/O here */
- if ( !*obdo ) {
- OIDEBUG(inode);
- *obdo = obdo_fromid(IID(inode), inode->i_ino,
- OBD_MD_FLNOTOBD);
- if ( IS_ERR(*obdo) ) {
- int err = PTR_ERR(*obdo);
- *obdo = NULL;
-
- EXIT;
- return err;
- }
-
- /* FIXME revisit fromid & from_inode */
- obdfs_from_inode(*obdo, inode);
- *flag = OBD_BRW_CREATE;
- }
-
- /* Remove request from list before write to avoid conflict.
- * Note that obdfs_pgrq_del() also deletes the request.
- */
- obdfs_pgrq_del(req);
- if ( !page ) {
- CDEBUG(D_CACHE, "no page \n");
- continue;
- }
-
- bufs[num] = (char *)page_address(page);
- pages[num] = page;
- counts[num] = PAGE_SIZE;
- offsets[num] = ((obd_off)page->index) << PAGE_SHIFT;
- CDEBUG(D_INFO, "ENQ inode %ld, page %p addr %p to vector\n",
- inode->i_ino, page, (char *)page_address(page));
- num++;
- }
-
- if (!list_empty(page_list))
- CDEBUG(D_INFO, "inode %ld list not empty\n", inode->i_ino);
- CDEBUG(D_INFO, "added %d page(s) to vector\n", num);
-
- EXIT;
- return num;
-} /* obdfs_enqueue_pages */
-
-/* Dequeue cached pages for a dying inode without writing them to disk. */
-void obdfs_dequeue_pages(struct inode *inode)
-{
- struct list_head *tmp;
-
- ENTRY;
- obd_down(&obdfs_i2sbi(inode)->osi_list_mutex);
- tmp = obdfs_islist(inode);
- if ( list_empty(tmp) ) {
- CDEBUG(D_INFO, "no dirty pages for inode %ld\n", inode->i_ino);
- obd_up(&obdfs_i2sbi(inode)->osi_list_mutex);
- EXIT;
- return;
- }
-
- /* take it out of the super list */
- list_del(tmp);
- INIT_LIST_HEAD(obdfs_islist(inode));
-
- tmp = obdfs_iplist(inode);
- while ( (tmp = tmp->prev) != obdfs_iplist(inode) ) {
- struct obdfs_pgrq *req;
- struct page *page;
-
- req = list_entry(tmp, struct obdfs_pgrq, rq_plist);
- page = req->rq_page;
- /* take it out of the list and free */
- obdfs_pgrq_del(req);
- /* now put the page away */
- put_page(page);
- }
-
- obd_up(&obdfs_i2sbi(inode)->osi_list_mutex);
-
- /* decrement inode reference for page cache */
- atomic_dec(&inode->i_count);
- EXIT;
-}
-
-/* This value is not arbitrarily chosen. KIO_STATIC_PAGES from linux/iobuf.h */
-#define MAX_IOVEC (KIO_STATIC_PAGES - 1)
-
-/* Remove writeback requests for the superblock */
-int obdfs_flush_reqs(struct list_head *inode_list, unsigned long check_time)
-{
- struct list_head *tmp;
- unsigned long max_io, total_io = 0;
- obd_count num_io;
- obd_count num_obdos;
- struct inode *inodes[MAX_IOVEC]; /* write data back to these */
- struct page *pages[MAX_IOVEC]; /* call put_page on these */
- struct obdo *obdos[MAX_IOVEC];
- char *bufs[MAX_IOVEC];
- obd_size counts[MAX_IOVEC];
- obd_off offsets[MAX_IOVEC];
- obd_flag flags[MAX_IOVEC];
- obd_count bufs_per_obdo[MAX_IOVEC];
- int err = 0;
- struct obdfs_sb_info *sbi;
-
- ENTRY;
- if (!inode_list) {
- CDEBUG(D_INODE, "no list\n");
- EXIT;
- return 0;
- }
-
- sbi = list_entry(inode_list, struct obdfs_sb_info, osi_inodes);
-
- obd_down(&sbi->osi_list_mutex);
- if ( list_empty(inode_list) ) {
- CDEBUG(D_INFO, "list empty\n");
- obd_up(&sbi->osi_list_mutex);
- EXIT;
- return 0;
- }
-
- /* If we are forcing a write, write out all dirty pages */
- max_io = check_time == ~0UL ? 1<<31 : pupdated.parms.ndirty;
- CDEBUG(D_INFO, "max_io = %lu\n", max_io);
-
- /* Add each inode's dirty pages to a write vector, and write it.
- * Traverse list in reverse order, so we do FIFO, not LIFO order
- */
- again:
- tmp = inode_list;
- num_io = 0;
- num_obdos = 0;
- while ( (tmp = tmp->prev) != inode_list && total_io < max_io) {
- struct obdfs_inode_info *ii;
- struct inode *inode;
- int res;
-
- ii = list_entry(tmp, struct obdfs_inode_info, oi_inodes);
- inode = list_entry(ii, struct inode, u);
- inodes[num_obdos] = inode;
- obdos[num_obdos] = NULL;
- CDEBUG(D_INFO, "checking inode %ld pages\n", inode->i_ino);
-
- /* Make sure we reference "inode" and not "inodes[num_obdos]",
- * as num_obdos will change after the loop is run.
- */
- if (!list_empty(obdfs_iplist(inode))) {
- res = obdfs_enqueue_pages(inode, &obdos[num_obdos],
- MAX_IOVEC - num_io,
- &pages[num_io], &bufs[num_io],
- &counts[num_io],
- &offsets[num_io],
- &flags[num_obdos],
- check_time);
- CDEBUG(D_INFO, "FLUSH inode %ld, pages flushed: %d\n",
- inode->i_ino, res);
- if ( res < 0 ) {
- CDEBUG(D_INODE,
- "fatal: unable to enqueue inode %ld (err %d)\n",
- inode->i_ino, res);
- /* XXX Move bad inode to end of list so we can
- * continue with flushing list. This is a
- * temporary measure to avoid machine lockups.
- * Maybe if we have -ENOENT, simply discard.
- */
- list_del(tmp);
- list_add(tmp, inode_list);
- err = res;
- EXIT;
- goto BREAK;
- }
- if (res == 0)
- continue;
-
- num_io += res;
- total_io += res;
- bufs_per_obdo[num_obdos] = res;
- num_obdos++;
-
- if ( num_io == MAX_IOVEC ) {
- obd_up(&sbi->osi_list_mutex);
- err = obdfs_do_vec_wr(inodes, num_io, num_obdos,
- obdos, bufs_per_obdo,
- pages, bufs, counts,
- offsets, flags);
- if ( err ) {
- CDEBUG(D_INODE,
- "fatal: do_vec_wr err=%d\n",
- err);
- EXIT;
- goto ERR;
- }
- obd_down(&sbi->osi_list_mutex);
- goto again;
- }
- }
- }
-
-BREAK:
- obd_up(&sbi->osi_list_mutex);
-
- /* flush any remaining I/Os */
- if ( num_io ) {
- err = obdfs_do_vec_wr(inodes, num_io, num_obdos, obdos,
- bufs_per_obdo, pages, bufs, counts,
- offsets, flags);
- if (err)
- CDEBUG(D_INODE, "fatal: unable to do vec_wr (err %d)\n", err);
- num_io = 0;
- num_obdos = 0;
- }
-
- /* Remove inode from superblock dirty list when no more pages.
- * Make sure we don't point at the current inode with tmp
- * when we re-init the list on the inode, or we will loop.
- */
- obd_down(&sbi->osi_list_mutex);
- tmp = inode_list;
- while ( (tmp = tmp->prev) != inode_list ) {
- struct obdfs_inode_info *ii;
- struct inode *inode;
-
- ii = list_entry(tmp, struct obdfs_inode_info, oi_inodes);
- inode = list_entry(ii, struct inode, u);
- CDEBUG(D_INFO, "checking inode %ld empty\n", inode->i_ino);
- if (list_empty(obdfs_iplist(inode))) {
- CDEBUG(D_INFO, "remove inode %ld from dirty list\n",
- inode->i_ino);
- tmp = tmp->next;
- list_del(obdfs_islist(inode));
- /* decrement inode reference for page cache */
- atomic_dec(&inode->i_count);
- INIT_LIST_HEAD(obdfs_islist(inode));
- }
- }
- obd_up(&sbi->osi_list_mutex);
-
- CDEBUG(D_INFO, "flushed %ld pages in total\n", total_io);
- EXIT;
-ERR:
- return err ? err : total_io;
-} /* obdfs_flush_reqs */
-
-
-/* Walk all of the superblocks and write out blocks which are too old.
- * Return the maximum number of blocks written for a single filesystem.
- */
-int obdfs_flush_dirty_pages(unsigned long check_time)
-{
- struct list_head *sl;
- int max = 0;
-
- /* ENTRY; */
- sl = &obdfs_super_list;
- while ( (sl = sl->prev) != &obdfs_super_list ) {
- struct obdfs_sb_info *sbi =
- list_entry(sl, struct obdfs_sb_info, osi_list);
- int ret;
-
- /* walk write requests here, use the sb, check the time */
- ret = obdfs_flush_reqs(&sbi->osi_inodes, check_time);
- /* XXX handle error? What to do with it? */
-
- max = ret > max ? ret : max;
- }
- if (max) { EXIT; }
- return max;
-} /* obdfs_flush_dirty_pages */
-
-
-static void pupdate_wakeup(unsigned long l)
-{
- wake_up(&pupdated.waitq);
-}
-
-
-static int pupdate(void *unused)
-{
- u_long flags;
- int interval = pupdated.parms.interval;
- long age = pupdated.parms.age_buffer;
- int wrote = 0;
-
- if (pupdated.active >= 0) {
- CDEBUG(D_CACHE, "attempted to run multiple pupdates\n");
- return 1;
- }
-
- init_timer(&pupdated.timer);
- init_waitqueue_head(&pupdated.waitq);
- pupdated.timer.function = pupdate_wakeup;
-
- exit_files(current);
- exit_mm(current);
- daemonize();
-
- current->session = 1;
- current->pgrp = 1;
- strcpy(current->comm, "pupdated");
-
- CDEBUG(D_CACHE, "pupdated activated...\n");
- pupdated.active = 1;
-
- spin_lock_irqsave(¤t->sigmask_lock, flags);
- flush_signals(current);
- sigfillset(¤t->blocked);
- recalc_sigpending(current);
- spin_unlock_irqrestore(¤t->sigmask_lock, flags);
-
- do {
- long dirty_limit;
-
- /* update interval */
- if (pupdated.active == 1 && interval) {
- mod_timer(&pupdated.timer, jiffies + interval);
- interruptible_sleep_on(&pupdated.waitq);
- }
- if (pupdated.active == 0) {
- del_timer(&pupdated.timer);
- /* If stopped, we flush one last time... */
- }
-
- /* asynchronous setattr etc for the future ...
- obdfs_flush_dirty_inodes(jiffies - pupdated.parms.age_super);
- */
- dirty_limit = nr_free_buffer_pages() * pupdated.parms.nfract / 100;
-
- if (obdfs_cache_count > dirty_limit) {
- interval = 0;
- if (wrote < pupdated.parms.ndirty)
- age >>= 1;
- if (wrote)
- CDEBUG(D_CACHE, "wrote %d, age %ld, interval %d\n",
- wrote, age, interval);
- } else {
- if (wrote < pupdated.parms.ndirty >> 1 &&
- obdfs_cache_count < dirty_limit / 2) {
- interval = pupdated.parms.interval;
- age = pupdated.parms.age_buffer;
- if (wrote)
- CDEBUG(D_INFO,
- "wrote %d, age %ld, interval %d\n",
- wrote, age, interval);
- } else if (obdfs_cache_count > dirty_limit / 2) {
- interval >>= 1;
- if (wrote < pupdated.parms.ndirty)
- age >>= 1;
- if (wrote)
- CDEBUG(D_CACHE,
- "wrote %d, age %ld, interval %d\n",
- wrote, age, interval);
- }
- }
-
- wrote = obdfs_flush_dirty_pages(jiffies - age);
- if (wrote) {
- CDEBUG(D_CACHE,
- "dirty_limit %ld, cache_count %ld, wrote %d\n",
- dirty_limit, obdfs_cache_count, wrote);
- run_task_queue(&tq_disk);
- }
- } while (pupdated.active == 1);
-
- CDEBUG(D_CACHE, "pupdated stopped...\n");
- pupdated.active = -1;
- wake_up(&pupdated.waitq);
- return 0;
-}
-
-
-int obdfs_flushd_init(void)
-{
- /*
- kernel_thread(bdflush, NULL, CLONE_FS | CLONE_FILES | CLONE_SIGHAND);
- */
- kernel_thread(pupdate, NULL, 0);
- CDEBUG(D_PSDEV, "flushd inited\n");
- return 0;
-}
-
-int obdfs_flushd_cleanup(void)
-{
- ENTRY;
-
- /* Shut down pupdated. */
- if (pupdated.active > 0) {
- CDEBUG(D_CACHE, "inform pupdated\n");
- pupdated.active = 0;
- wake_up(&pupdated.waitq);
-
- CDEBUG(D_CACHE, "wait for pupdated\n");
- while (pupdated.active == 0) {
- interruptible_sleep_on(&pupdated.waitq);
- }
- CDEBUG(D_CACHE, "done waiting for pupdated\n");
- }
-
- EXIT;
- return 0;
-}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff