![Jens Axboe](/assets/img/avatar_default.png)
They should be reimplemented in the current scheme. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
1425 lines
38 KiB
C
1425 lines
38 KiB
C
/*
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drbd_actlog.c
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This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
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Copyright (C) 2003-2008, LINBIT Information Technologies GmbH.
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Copyright (C) 2003-2008, Philipp Reisner <philipp.reisner@linbit.com>.
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Copyright (C) 2003-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
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drbd is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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drbd is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with drbd; see the file COPYING. If not, write to
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the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <linux/slab.h>
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#include <linux/drbd.h>
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#include "drbd_int.h"
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#include "drbd_wrappers.h"
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/* We maintain a trivial check sum in our on disk activity log.
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* With that we can ensure correct operation even when the storage
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* device might do a partial (last) sector write while loosing power.
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*/
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struct __packed al_transaction {
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u32 magic;
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u32 tr_number;
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struct __packed {
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u32 pos;
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u32 extent; } updates[1 + AL_EXTENTS_PT];
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u32 xor_sum;
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};
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struct update_odbm_work {
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struct drbd_work w;
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unsigned int enr;
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};
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struct update_al_work {
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struct drbd_work w;
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struct lc_element *al_ext;
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struct completion event;
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unsigned int enr;
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/* if old_enr != LC_FREE, write corresponding bitmap sector, too */
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unsigned int old_enr;
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};
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struct drbd_atodb_wait {
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atomic_t count;
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struct completion io_done;
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struct drbd_conf *mdev;
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int error;
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};
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int w_al_write_transaction(struct drbd_conf *, struct drbd_work *, int);
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static int _drbd_md_sync_page_io(struct drbd_conf *mdev,
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struct drbd_backing_dev *bdev,
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struct page *page, sector_t sector,
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int rw, int size)
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{
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struct bio *bio;
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struct drbd_md_io md_io;
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int ok;
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md_io.mdev = mdev;
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init_completion(&md_io.event);
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md_io.error = 0;
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if ((rw & WRITE) && !test_bit(MD_NO_BARRIER, &mdev->flags))
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rw |= (1 << BIO_RW_BARRIER);
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rw |= ((1<<BIO_RW_UNPLUG) | (1<<BIO_RW_SYNCIO));
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retry:
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bio = bio_alloc(GFP_NOIO, 1);
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bio->bi_bdev = bdev->md_bdev;
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bio->bi_sector = sector;
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ok = (bio_add_page(bio, page, size, 0) == size);
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if (!ok)
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goto out;
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bio->bi_private = &md_io;
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bio->bi_end_io = drbd_md_io_complete;
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bio->bi_rw = rw;
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if (FAULT_ACTIVE(mdev, (rw & WRITE) ? DRBD_FAULT_MD_WR : DRBD_FAULT_MD_RD))
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bio_endio(bio, -EIO);
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else
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submit_bio(rw, bio);
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wait_for_completion(&md_io.event);
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ok = bio_flagged(bio, BIO_UPTODATE) && md_io.error == 0;
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/* check for unsupported barrier op.
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* would rather check on EOPNOTSUPP, but that is not reliable.
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* don't try again for ANY return value != 0 */
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if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER) && !ok)) {
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/* Try again with no barrier */
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dev_warn(DEV, "Barriers not supported on meta data device - disabling\n");
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set_bit(MD_NO_BARRIER, &mdev->flags);
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rw &= ~(1 << BIO_RW_BARRIER);
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bio_put(bio);
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goto retry;
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}
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out:
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bio_put(bio);
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return ok;
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}
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int drbd_md_sync_page_io(struct drbd_conf *mdev, struct drbd_backing_dev *bdev,
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sector_t sector, int rw)
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{
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int logical_block_size, mask, ok;
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int offset = 0;
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struct page *iop = mdev->md_io_page;
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D_ASSERT(mutex_is_locked(&mdev->md_io_mutex));
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BUG_ON(!bdev->md_bdev);
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logical_block_size = bdev_logical_block_size(bdev->md_bdev);
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if (logical_block_size == 0)
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logical_block_size = MD_SECTOR_SIZE;
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/* in case logical_block_size != 512 [ s390 only? ] */
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if (logical_block_size != MD_SECTOR_SIZE) {
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mask = (logical_block_size / MD_SECTOR_SIZE) - 1;
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D_ASSERT(mask == 1 || mask == 3 || mask == 7);
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D_ASSERT(logical_block_size == (mask+1) * MD_SECTOR_SIZE);
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offset = sector & mask;
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sector = sector & ~mask;
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iop = mdev->md_io_tmpp;
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if (rw & WRITE) {
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/* these are GFP_KERNEL pages, pre-allocated
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* on device initialization */
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void *p = page_address(mdev->md_io_page);
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void *hp = page_address(mdev->md_io_tmpp);
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ok = _drbd_md_sync_page_io(mdev, bdev, iop, sector,
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READ, logical_block_size);
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if (unlikely(!ok)) {
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dev_err(DEV, "drbd_md_sync_page_io(,%llus,"
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"READ [logical_block_size!=512]) failed!\n",
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(unsigned long long)sector);
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return 0;
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}
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memcpy(hp + offset*MD_SECTOR_SIZE, p, MD_SECTOR_SIZE);
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}
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}
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if (sector < drbd_md_first_sector(bdev) ||
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sector > drbd_md_last_sector(bdev))
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dev_alert(DEV, "%s [%d]:%s(,%llus,%s) out of range md access!\n",
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current->comm, current->pid, __func__,
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(unsigned long long)sector, (rw & WRITE) ? "WRITE" : "READ");
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ok = _drbd_md_sync_page_io(mdev, bdev, iop, sector, rw, logical_block_size);
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if (unlikely(!ok)) {
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dev_err(DEV, "drbd_md_sync_page_io(,%llus,%s) failed!\n",
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(unsigned long long)sector, (rw & WRITE) ? "WRITE" : "READ");
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return 0;
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}
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if (logical_block_size != MD_SECTOR_SIZE && !(rw & WRITE)) {
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void *p = page_address(mdev->md_io_page);
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void *hp = page_address(mdev->md_io_tmpp);
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memcpy(p, hp + offset*MD_SECTOR_SIZE, MD_SECTOR_SIZE);
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}
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return ok;
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}
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static struct lc_element *_al_get(struct drbd_conf *mdev, unsigned int enr)
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{
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struct lc_element *al_ext;
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struct lc_element *tmp;
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unsigned long al_flags = 0;
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spin_lock_irq(&mdev->al_lock);
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tmp = lc_find(mdev->resync, enr/AL_EXT_PER_BM_SECT);
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if (unlikely(tmp != NULL)) {
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struct bm_extent *bm_ext = lc_entry(tmp, struct bm_extent, lce);
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if (test_bit(BME_NO_WRITES, &bm_ext->flags)) {
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spin_unlock_irq(&mdev->al_lock);
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return NULL;
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}
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}
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al_ext = lc_get(mdev->act_log, enr);
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al_flags = mdev->act_log->flags;
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spin_unlock_irq(&mdev->al_lock);
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/*
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if (!al_ext) {
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if (al_flags & LC_STARVING)
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dev_warn(DEV, "Have to wait for LRU element (AL too small?)\n");
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if (al_flags & LC_DIRTY)
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dev_warn(DEV, "Ongoing AL update (AL device too slow?)\n");
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}
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*/
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return al_ext;
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}
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void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector)
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{
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unsigned int enr = (sector >> (AL_EXTENT_SHIFT-9));
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struct lc_element *al_ext;
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struct update_al_work al_work;
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D_ASSERT(atomic_read(&mdev->local_cnt) > 0);
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wait_event(mdev->al_wait, (al_ext = _al_get(mdev, enr)));
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if (al_ext->lc_number != enr) {
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/* drbd_al_write_transaction(mdev,al_ext,enr);
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* recurses into generic_make_request(), which
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* disallows recursion, bios being serialized on the
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* current->bio_tail list now.
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* we have to delegate updates to the activity log
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* to the worker thread. */
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init_completion(&al_work.event);
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al_work.al_ext = al_ext;
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al_work.enr = enr;
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al_work.old_enr = al_ext->lc_number;
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al_work.w.cb = w_al_write_transaction;
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drbd_queue_work_front(&mdev->data.work, &al_work.w);
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wait_for_completion(&al_work.event);
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mdev->al_writ_cnt++;
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spin_lock_irq(&mdev->al_lock);
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lc_changed(mdev->act_log, al_ext);
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spin_unlock_irq(&mdev->al_lock);
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wake_up(&mdev->al_wait);
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}
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}
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void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector)
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{
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unsigned int enr = (sector >> (AL_EXTENT_SHIFT-9));
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struct lc_element *extent;
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unsigned long flags;
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spin_lock_irqsave(&mdev->al_lock, flags);
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extent = lc_find(mdev->act_log, enr);
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if (!extent) {
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spin_unlock_irqrestore(&mdev->al_lock, flags);
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dev_err(DEV, "al_complete_io() called on inactive extent %u\n", enr);
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return;
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}
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if (lc_put(mdev->act_log, extent) == 0)
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wake_up(&mdev->al_wait);
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spin_unlock_irqrestore(&mdev->al_lock, flags);
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}
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int
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w_al_write_transaction(struct drbd_conf *mdev, struct drbd_work *w, int unused)
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{
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struct update_al_work *aw = container_of(w, struct update_al_work, w);
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struct lc_element *updated = aw->al_ext;
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const unsigned int new_enr = aw->enr;
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const unsigned int evicted = aw->old_enr;
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struct al_transaction *buffer;
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sector_t sector;
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int i, n, mx;
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unsigned int extent_nr;
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u32 xor_sum = 0;
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if (!get_ldev(mdev)) {
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dev_err(DEV, "get_ldev() failed in w_al_write_transaction\n");
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complete(&((struct update_al_work *)w)->event);
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return 1;
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}
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/* do we have to do a bitmap write, first?
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* TODO reduce maximum latency:
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* submit both bios, then wait for both,
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* instead of doing two synchronous sector writes. */
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if (mdev->state.conn < C_CONNECTED && evicted != LC_FREE)
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drbd_bm_write_sect(mdev, evicted/AL_EXT_PER_BM_SECT);
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mutex_lock(&mdev->md_io_mutex); /* protects md_io_page, al_tr_cycle, ... */
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buffer = (struct al_transaction *)page_address(mdev->md_io_page);
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buffer->magic = __constant_cpu_to_be32(DRBD_MAGIC);
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buffer->tr_number = cpu_to_be32(mdev->al_tr_number);
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n = lc_index_of(mdev->act_log, updated);
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buffer->updates[0].pos = cpu_to_be32(n);
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buffer->updates[0].extent = cpu_to_be32(new_enr);
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xor_sum ^= new_enr;
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mx = min_t(int, AL_EXTENTS_PT,
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mdev->act_log->nr_elements - mdev->al_tr_cycle);
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for (i = 0; i < mx; i++) {
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unsigned idx = mdev->al_tr_cycle + i;
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extent_nr = lc_element_by_index(mdev->act_log, idx)->lc_number;
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buffer->updates[i+1].pos = cpu_to_be32(idx);
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buffer->updates[i+1].extent = cpu_to_be32(extent_nr);
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xor_sum ^= extent_nr;
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}
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for (; i < AL_EXTENTS_PT; i++) {
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buffer->updates[i+1].pos = __constant_cpu_to_be32(-1);
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buffer->updates[i+1].extent = __constant_cpu_to_be32(LC_FREE);
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xor_sum ^= LC_FREE;
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}
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mdev->al_tr_cycle += AL_EXTENTS_PT;
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if (mdev->al_tr_cycle >= mdev->act_log->nr_elements)
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mdev->al_tr_cycle = 0;
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buffer->xor_sum = cpu_to_be32(xor_sum);
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sector = mdev->ldev->md.md_offset
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+ mdev->ldev->md.al_offset + mdev->al_tr_pos;
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if (!drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE))
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drbd_chk_io_error(mdev, 1, TRUE);
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if (++mdev->al_tr_pos >
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div_ceil(mdev->act_log->nr_elements, AL_EXTENTS_PT))
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mdev->al_tr_pos = 0;
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D_ASSERT(mdev->al_tr_pos < MD_AL_MAX_SIZE);
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mdev->al_tr_number++;
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mutex_unlock(&mdev->md_io_mutex);
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complete(&((struct update_al_work *)w)->event);
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put_ldev(mdev);
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return 1;
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}
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/**
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* drbd_al_read_tr() - Read a single transaction from the on disk activity log
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* @mdev: DRBD device.
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* @bdev: Block device to read form.
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* @b: pointer to an al_transaction.
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* @index: On disk slot of the transaction to read.
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*
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* Returns -1 on IO error, 0 on checksum error and 1 upon success.
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*/
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static int drbd_al_read_tr(struct drbd_conf *mdev,
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struct drbd_backing_dev *bdev,
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struct al_transaction *b,
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int index)
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{
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sector_t sector;
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int rv, i;
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u32 xor_sum = 0;
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sector = bdev->md.md_offset + bdev->md.al_offset + index;
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/* Dont process error normally,
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* as this is done before disk is attached! */
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if (!drbd_md_sync_page_io(mdev, bdev, sector, READ))
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return -1;
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rv = (be32_to_cpu(b->magic) == DRBD_MAGIC);
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for (i = 0; i < AL_EXTENTS_PT + 1; i++)
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xor_sum ^= be32_to_cpu(b->updates[i].extent);
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rv &= (xor_sum == be32_to_cpu(b->xor_sum));
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return rv;
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}
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/**
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* drbd_al_read_log() - Restores the activity log from its on disk representation.
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* @mdev: DRBD device.
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* @bdev: Block device to read form.
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*
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* Returns 1 on success, returns 0 when reading the log failed due to IO errors.
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*/
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int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
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{
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struct al_transaction *buffer;
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int i;
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int rv;
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int mx;
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int active_extents = 0;
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int transactions = 0;
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int found_valid = 0;
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int from = 0;
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int to = 0;
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u32 from_tnr = 0;
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u32 to_tnr = 0;
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u32 cnr;
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mx = div_ceil(mdev->act_log->nr_elements, AL_EXTENTS_PT);
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/* lock out all other meta data io for now,
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* and make sure the page is mapped.
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*/
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mutex_lock(&mdev->md_io_mutex);
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buffer = page_address(mdev->md_io_page);
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/* Find the valid transaction in the log */
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for (i = 0; i <= mx; i++) {
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rv = drbd_al_read_tr(mdev, bdev, buffer, i);
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if (rv == 0)
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continue;
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if (rv == -1) {
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mutex_unlock(&mdev->md_io_mutex);
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return 0;
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}
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cnr = be32_to_cpu(buffer->tr_number);
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if (++found_valid == 1) {
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from = i;
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to = i;
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from_tnr = cnr;
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to_tnr = cnr;
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continue;
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}
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if ((int)cnr - (int)from_tnr < 0) {
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D_ASSERT(from_tnr - cnr + i - from == mx+1);
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from = i;
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from_tnr = cnr;
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}
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if ((int)cnr - (int)to_tnr > 0) {
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D_ASSERT(cnr - to_tnr == i - to);
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to = i;
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to_tnr = cnr;
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}
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}
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if (!found_valid) {
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dev_warn(DEV, "No usable activity log found.\n");
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mutex_unlock(&mdev->md_io_mutex);
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return 1;
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}
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/* Read the valid transactions.
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* dev_info(DEV, "Reading from %d to %d.\n",from,to); */
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i = from;
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while (1) {
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int j, pos;
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unsigned int extent_nr;
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unsigned int trn;
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rv = drbd_al_read_tr(mdev, bdev, buffer, i);
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ERR_IF(rv == 0) goto cancel;
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if (rv == -1) {
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mutex_unlock(&mdev->md_io_mutex);
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return 0;
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}
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trn = be32_to_cpu(buffer->tr_number);
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spin_lock_irq(&mdev->al_lock);
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/* This loop runs backwards because in the cyclic
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elements there might be an old version of the
|
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updated element (in slot 0). So the element in slot 0
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can overwrite old versions. */
|
|
for (j = AL_EXTENTS_PT; j >= 0; j--) {
|
|
pos = be32_to_cpu(buffer->updates[j].pos);
|
|
extent_nr = be32_to_cpu(buffer->updates[j].extent);
|
|
|
|
if (extent_nr == LC_FREE)
|
|
continue;
|
|
|
|
lc_set(mdev->act_log, extent_nr, pos);
|
|
active_extents++;
|
|
}
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
|
|
transactions++;
|
|
|
|
cancel:
|
|
if (i == to)
|
|
break;
|
|
i++;
|
|
if (i > mx)
|
|
i = 0;
|
|
}
|
|
|
|
mdev->al_tr_number = to_tnr+1;
|
|
mdev->al_tr_pos = to;
|
|
if (++mdev->al_tr_pos >
|
|
div_ceil(mdev->act_log->nr_elements, AL_EXTENTS_PT))
|
|
mdev->al_tr_pos = 0;
|
|
|
|
/* ok, we are done with it */
|
|
mutex_unlock(&mdev->md_io_mutex);
|
|
|
|
dev_info(DEV, "Found %d transactions (%d active extents) in activity log.\n",
|
|
transactions, active_extents);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static void atodb_endio(struct bio *bio, int error)
|
|
{
|
|
struct drbd_atodb_wait *wc = bio->bi_private;
|
|
struct drbd_conf *mdev = wc->mdev;
|
|
struct page *page;
|
|
int uptodate = bio_flagged(bio, BIO_UPTODATE);
|
|
|
|
/* strange behavior of some lower level drivers...
|
|
* fail the request by clearing the uptodate flag,
|
|
* but do not return any error?! */
|
|
if (!error && !uptodate)
|
|
error = -EIO;
|
|
|
|
drbd_chk_io_error(mdev, error, TRUE);
|
|
if (error && wc->error == 0)
|
|
wc->error = error;
|
|
|
|
if (atomic_dec_and_test(&wc->count))
|
|
complete(&wc->io_done);
|
|
|
|
page = bio->bi_io_vec[0].bv_page;
|
|
put_page(page);
|
|
bio_put(bio);
|
|
mdev->bm_writ_cnt++;
|
|
put_ldev(mdev);
|
|
}
|
|
|
|
#define S2W(s) ((s)<<(BM_EXT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL))
|
|
/* activity log to on disk bitmap -- prepare bio unless that sector
|
|
* is already covered by previously prepared bios */
|
|
static int atodb_prepare_unless_covered(struct drbd_conf *mdev,
|
|
struct bio **bios,
|
|
unsigned int enr,
|
|
struct drbd_atodb_wait *wc) __must_hold(local)
|
|
{
|
|
struct bio *bio;
|
|
struct page *page;
|
|
sector_t on_disk_sector = enr + mdev->ldev->md.md_offset
|
|
+ mdev->ldev->md.bm_offset;
|
|
unsigned int page_offset = PAGE_SIZE;
|
|
int offset;
|
|
int i = 0;
|
|
int err = -ENOMEM;
|
|
|
|
/* Check if that enr is already covered by an already created bio.
|
|
* Caution, bios[] is not NULL terminated,
|
|
* but only initialized to all NULL.
|
|
* For completely scattered activity log,
|
|
* the last invocation iterates over all bios,
|
|
* and finds the last NULL entry.
|
|
*/
|
|
while ((bio = bios[i])) {
|
|
if (bio->bi_sector == on_disk_sector)
|
|
return 0;
|
|
i++;
|
|
}
|
|
/* bios[i] == NULL, the next not yet used slot */
|
|
|
|
/* GFP_KERNEL, we are not in the write-out path */
|
|
bio = bio_alloc(GFP_KERNEL, 1);
|
|
if (bio == NULL)
|
|
return -ENOMEM;
|
|
|
|
if (i > 0) {
|
|
const struct bio_vec *prev_bv = bios[i-1]->bi_io_vec;
|
|
page_offset = prev_bv->bv_offset + prev_bv->bv_len;
|
|
page = prev_bv->bv_page;
|
|
}
|
|
if (page_offset == PAGE_SIZE) {
|
|
page = alloc_page(__GFP_HIGHMEM);
|
|
if (page == NULL)
|
|
goto out_bio_put;
|
|
page_offset = 0;
|
|
} else {
|
|
get_page(page);
|
|
}
|
|
|
|
offset = S2W(enr);
|
|
drbd_bm_get_lel(mdev, offset,
|
|
min_t(size_t, S2W(1), drbd_bm_words(mdev) - offset),
|
|
kmap(page) + page_offset);
|
|
kunmap(page);
|
|
|
|
bio->bi_private = wc;
|
|
bio->bi_end_io = atodb_endio;
|
|
bio->bi_bdev = mdev->ldev->md_bdev;
|
|
bio->bi_sector = on_disk_sector;
|
|
|
|
if (bio_add_page(bio, page, MD_SECTOR_SIZE, page_offset) != MD_SECTOR_SIZE)
|
|
goto out_put_page;
|
|
|
|
atomic_inc(&wc->count);
|
|
/* we already know that we may do this...
|
|
* get_ldev_if_state(mdev,D_ATTACHING);
|
|
* just get the extra reference, so that the local_cnt reflects
|
|
* the number of pending IO requests DRBD at its backing device.
|
|
*/
|
|
atomic_inc(&mdev->local_cnt);
|
|
|
|
bios[i] = bio;
|
|
|
|
return 0;
|
|
|
|
out_put_page:
|
|
err = -EINVAL;
|
|
put_page(page);
|
|
out_bio_put:
|
|
bio_put(bio);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* drbd_al_to_on_disk_bm() - * Writes bitmap parts covered by active AL extents
|
|
* @mdev: DRBD device.
|
|
*
|
|
* Called when we detach (unconfigure) local storage,
|
|
* or when we go from R_PRIMARY to R_SECONDARY role.
|
|
*/
|
|
void drbd_al_to_on_disk_bm(struct drbd_conf *mdev)
|
|
{
|
|
int i, nr_elements;
|
|
unsigned int enr;
|
|
struct bio **bios;
|
|
struct drbd_atodb_wait wc;
|
|
|
|
ERR_IF (!get_ldev_if_state(mdev, D_ATTACHING))
|
|
return; /* sorry, I don't have any act_log etc... */
|
|
|
|
wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
|
|
|
|
nr_elements = mdev->act_log->nr_elements;
|
|
|
|
/* GFP_KERNEL, we are not in anyone's write-out path */
|
|
bios = kzalloc(sizeof(struct bio *) * nr_elements, GFP_KERNEL);
|
|
if (!bios)
|
|
goto submit_one_by_one;
|
|
|
|
atomic_set(&wc.count, 0);
|
|
init_completion(&wc.io_done);
|
|
wc.mdev = mdev;
|
|
wc.error = 0;
|
|
|
|
for (i = 0; i < nr_elements; i++) {
|
|
enr = lc_element_by_index(mdev->act_log, i)->lc_number;
|
|
if (enr == LC_FREE)
|
|
continue;
|
|
/* next statement also does atomic_inc wc.count and local_cnt */
|
|
if (atodb_prepare_unless_covered(mdev, bios,
|
|
enr/AL_EXT_PER_BM_SECT,
|
|
&wc))
|
|
goto free_bios_submit_one_by_one;
|
|
}
|
|
|
|
/* unnecessary optimization? */
|
|
lc_unlock(mdev->act_log);
|
|
wake_up(&mdev->al_wait);
|
|
|
|
/* all prepared, submit them */
|
|
for (i = 0; i < nr_elements; i++) {
|
|
if (bios[i] == NULL)
|
|
break;
|
|
if (FAULT_ACTIVE(mdev, DRBD_FAULT_MD_WR)) {
|
|
bios[i]->bi_rw = WRITE;
|
|
bio_endio(bios[i], -EIO);
|
|
} else {
|
|
submit_bio(WRITE, bios[i]);
|
|
}
|
|
}
|
|
|
|
drbd_blk_run_queue(bdev_get_queue(mdev->ldev->md_bdev));
|
|
|
|
/* always (try to) flush bitmap to stable storage */
|
|
drbd_md_flush(mdev);
|
|
|
|
/* In case we did not submit a single IO do not wait for
|
|
* them to complete. ( Because we would wait forever here. )
|
|
*
|
|
* In case we had IOs and they are already complete, there
|
|
* is not point in waiting anyways.
|
|
* Therefore this if () ... */
|
|
if (atomic_read(&wc.count))
|
|
wait_for_completion(&wc.io_done);
|
|
|
|
put_ldev(mdev);
|
|
|
|
kfree(bios);
|
|
return;
|
|
|
|
free_bios_submit_one_by_one:
|
|
/* free everything by calling the endio callback directly. */
|
|
for (i = 0; i < nr_elements && bios[i]; i++)
|
|
bio_endio(bios[i], 0);
|
|
|
|
kfree(bios);
|
|
|
|
submit_one_by_one:
|
|
dev_warn(DEV, "Using the slow drbd_al_to_on_disk_bm()\n");
|
|
|
|
for (i = 0; i < mdev->act_log->nr_elements; i++) {
|
|
enr = lc_element_by_index(mdev->act_log, i)->lc_number;
|
|
if (enr == LC_FREE)
|
|
continue;
|
|
/* Really slow: if we have al-extents 16..19 active,
|
|
* sector 4 will be written four times! Synchronous! */
|
|
drbd_bm_write_sect(mdev, enr/AL_EXT_PER_BM_SECT);
|
|
}
|
|
|
|
lc_unlock(mdev->act_log);
|
|
wake_up(&mdev->al_wait);
|
|
put_ldev(mdev);
|
|
}
|
|
|
|
/**
|
|
* drbd_al_apply_to_bm() - Sets the bitmap to diry(1) where covered ba active AL extents
|
|
* @mdev: DRBD device.
|
|
*/
|
|
void drbd_al_apply_to_bm(struct drbd_conf *mdev)
|
|
{
|
|
unsigned int enr;
|
|
unsigned long add = 0;
|
|
char ppb[10];
|
|
int i;
|
|
|
|
wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
|
|
|
|
for (i = 0; i < mdev->act_log->nr_elements; i++) {
|
|
enr = lc_element_by_index(mdev->act_log, i)->lc_number;
|
|
if (enr == LC_FREE)
|
|
continue;
|
|
add += drbd_bm_ALe_set_all(mdev, enr);
|
|
}
|
|
|
|
lc_unlock(mdev->act_log);
|
|
wake_up(&mdev->al_wait);
|
|
|
|
dev_info(DEV, "Marked additional %s as out-of-sync based on AL.\n",
|
|
ppsize(ppb, Bit2KB(add)));
|
|
}
|
|
|
|
static int _try_lc_del(struct drbd_conf *mdev, struct lc_element *al_ext)
|
|
{
|
|
int rv;
|
|
|
|
spin_lock_irq(&mdev->al_lock);
|
|
rv = (al_ext->refcnt == 0);
|
|
if (likely(rv))
|
|
lc_del(mdev->act_log, al_ext);
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
|
|
return rv;
|
|
}
|
|
|
|
/**
|
|
* drbd_al_shrink() - Removes all active extents form the activity log
|
|
* @mdev: DRBD device.
|
|
*
|
|
* Removes all active extents form the activity log, waiting until
|
|
* the reference count of each entry dropped to 0 first, of course.
|
|
*
|
|
* You need to lock mdev->act_log with lc_try_lock() / lc_unlock()
|
|
*/
|
|
void drbd_al_shrink(struct drbd_conf *mdev)
|
|
{
|
|
struct lc_element *al_ext;
|
|
int i;
|
|
|
|
D_ASSERT(test_bit(__LC_DIRTY, &mdev->act_log->flags));
|
|
|
|
for (i = 0; i < mdev->act_log->nr_elements; i++) {
|
|
al_ext = lc_element_by_index(mdev->act_log, i);
|
|
if (al_ext->lc_number == LC_FREE)
|
|
continue;
|
|
wait_event(mdev->al_wait, _try_lc_del(mdev, al_ext));
|
|
}
|
|
|
|
wake_up(&mdev->al_wait);
|
|
}
|
|
|
|
static int w_update_odbm(struct drbd_conf *mdev, struct drbd_work *w, int unused)
|
|
{
|
|
struct update_odbm_work *udw = container_of(w, struct update_odbm_work, w);
|
|
|
|
if (!get_ldev(mdev)) {
|
|
if (__ratelimit(&drbd_ratelimit_state))
|
|
dev_warn(DEV, "Can not update on disk bitmap, local IO disabled.\n");
|
|
kfree(udw);
|
|
return 1;
|
|
}
|
|
|
|
drbd_bm_write_sect(mdev, udw->enr);
|
|
put_ldev(mdev);
|
|
|
|
kfree(udw);
|
|
|
|
if (drbd_bm_total_weight(mdev) <= mdev->rs_failed) {
|
|
switch (mdev->state.conn) {
|
|
case C_SYNC_SOURCE: case C_SYNC_TARGET:
|
|
case C_PAUSED_SYNC_S: case C_PAUSED_SYNC_T:
|
|
drbd_resync_finished(mdev);
|
|
default:
|
|
/* nothing to do */
|
|
break;
|
|
}
|
|
}
|
|
drbd_bcast_sync_progress(mdev);
|
|
|
|
return 1;
|
|
}
|
|
|
|
|
|
/* ATTENTION. The AL's extents are 4MB each, while the extents in the
|
|
* resync LRU-cache are 16MB each.
|
|
* The caller of this function has to hold an get_ldev() reference.
|
|
*
|
|
* TODO will be obsoleted once we have a caching lru of the on disk bitmap
|
|
*/
|
|
static void drbd_try_clear_on_disk_bm(struct drbd_conf *mdev, sector_t sector,
|
|
int count, int success)
|
|
{
|
|
struct lc_element *e;
|
|
struct update_odbm_work *udw;
|
|
|
|
unsigned int enr;
|
|
|
|
D_ASSERT(atomic_read(&mdev->local_cnt));
|
|
|
|
/* I simply assume that a sector/size pair never crosses
|
|
* a 16 MB extent border. (Currently this is true...) */
|
|
enr = BM_SECT_TO_EXT(sector);
|
|
|
|
e = lc_get(mdev->resync, enr);
|
|
if (e) {
|
|
struct bm_extent *ext = lc_entry(e, struct bm_extent, lce);
|
|
if (ext->lce.lc_number == enr) {
|
|
if (success)
|
|
ext->rs_left -= count;
|
|
else
|
|
ext->rs_failed += count;
|
|
if (ext->rs_left < ext->rs_failed) {
|
|
dev_err(DEV, "BAD! sector=%llus enr=%u rs_left=%d "
|
|
"rs_failed=%d count=%d\n",
|
|
(unsigned long long)sector,
|
|
ext->lce.lc_number, ext->rs_left,
|
|
ext->rs_failed, count);
|
|
dump_stack();
|
|
|
|
lc_put(mdev->resync, &ext->lce);
|
|
drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
|
|
return;
|
|
}
|
|
} else {
|
|
/* Normally this element should be in the cache,
|
|
* since drbd_rs_begin_io() pulled it already in.
|
|
*
|
|
* But maybe an application write finished, and we set
|
|
* something outside the resync lru_cache in sync.
|
|
*/
|
|
int rs_left = drbd_bm_e_weight(mdev, enr);
|
|
if (ext->flags != 0) {
|
|
dev_warn(DEV, "changing resync lce: %d[%u;%02lx]"
|
|
" -> %d[%u;00]\n",
|
|
ext->lce.lc_number, ext->rs_left,
|
|
ext->flags, enr, rs_left);
|
|
ext->flags = 0;
|
|
}
|
|
if (ext->rs_failed) {
|
|
dev_warn(DEV, "Kicking resync_lru element enr=%u "
|
|
"out with rs_failed=%d\n",
|
|
ext->lce.lc_number, ext->rs_failed);
|
|
set_bit(WRITE_BM_AFTER_RESYNC, &mdev->flags);
|
|
}
|
|
ext->rs_left = rs_left;
|
|
ext->rs_failed = success ? 0 : count;
|
|
lc_changed(mdev->resync, &ext->lce);
|
|
}
|
|
lc_put(mdev->resync, &ext->lce);
|
|
/* no race, we are within the al_lock! */
|
|
|
|
if (ext->rs_left == ext->rs_failed) {
|
|
ext->rs_failed = 0;
|
|
|
|
udw = kmalloc(sizeof(*udw), GFP_ATOMIC);
|
|
if (udw) {
|
|
udw->enr = ext->lce.lc_number;
|
|
udw->w.cb = w_update_odbm;
|
|
drbd_queue_work_front(&mdev->data.work, &udw->w);
|
|
} else {
|
|
dev_warn(DEV, "Could not kmalloc an udw\n");
|
|
set_bit(WRITE_BM_AFTER_RESYNC, &mdev->flags);
|
|
}
|
|
}
|
|
} else {
|
|
dev_err(DEV, "lc_get() failed! locked=%d/%d flags=%lu\n",
|
|
mdev->resync_locked,
|
|
mdev->resync->nr_elements,
|
|
mdev->resync->flags);
|
|
}
|
|
}
|
|
|
|
/* clear the bit corresponding to the piece of storage in question:
|
|
* size byte of data starting from sector. Only clear a bits of the affected
|
|
* one ore more _aligned_ BM_BLOCK_SIZE blocks.
|
|
*
|
|
* called by worker on C_SYNC_TARGET and receiver on SyncSource.
|
|
*
|
|
*/
|
|
void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector, int size,
|
|
const char *file, const unsigned int line)
|
|
{
|
|
/* Is called from worker and receiver context _only_ */
|
|
unsigned long sbnr, ebnr, lbnr;
|
|
unsigned long count = 0;
|
|
sector_t esector, nr_sectors;
|
|
int wake_up = 0;
|
|
unsigned long flags;
|
|
|
|
if (size <= 0 || (size & 0x1ff) != 0 || size > DRBD_MAX_SEGMENT_SIZE) {
|
|
dev_err(DEV, "drbd_set_in_sync: sector=%llus size=%d nonsense!\n",
|
|
(unsigned long long)sector, size);
|
|
return;
|
|
}
|
|
nr_sectors = drbd_get_capacity(mdev->this_bdev);
|
|
esector = sector + (size >> 9) - 1;
|
|
|
|
ERR_IF(sector >= nr_sectors) return;
|
|
ERR_IF(esector >= nr_sectors) esector = (nr_sectors-1);
|
|
|
|
lbnr = BM_SECT_TO_BIT(nr_sectors-1);
|
|
|
|
/* we clear it (in sync).
|
|
* round up start sector, round down end sector. we make sure we only
|
|
* clear full, aligned, BM_BLOCK_SIZE (4K) blocks */
|
|
if (unlikely(esector < BM_SECT_PER_BIT-1))
|
|
return;
|
|
if (unlikely(esector == (nr_sectors-1)))
|
|
ebnr = lbnr;
|
|
else
|
|
ebnr = BM_SECT_TO_BIT(esector - (BM_SECT_PER_BIT-1));
|
|
sbnr = BM_SECT_TO_BIT(sector + BM_SECT_PER_BIT-1);
|
|
|
|
if (sbnr > ebnr)
|
|
return;
|
|
|
|
/*
|
|
* ok, (capacity & 7) != 0 sometimes, but who cares...
|
|
* we count rs_{total,left} in bits, not sectors.
|
|
*/
|
|
spin_lock_irqsave(&mdev->al_lock, flags);
|
|
count = drbd_bm_clear_bits(mdev, sbnr, ebnr);
|
|
if (count) {
|
|
/* we need the lock for drbd_try_clear_on_disk_bm */
|
|
if (jiffies - mdev->rs_mark_time > HZ*10) {
|
|
/* should be rolling marks,
|
|
* but we estimate only anyways. */
|
|
if (mdev->rs_mark_left != drbd_bm_total_weight(mdev) &&
|
|
mdev->state.conn != C_PAUSED_SYNC_T &&
|
|
mdev->state.conn != C_PAUSED_SYNC_S) {
|
|
mdev->rs_mark_time = jiffies;
|
|
mdev->rs_mark_left = drbd_bm_total_weight(mdev);
|
|
}
|
|
}
|
|
if (get_ldev(mdev)) {
|
|
drbd_try_clear_on_disk_bm(mdev, sector, count, TRUE);
|
|
put_ldev(mdev);
|
|
}
|
|
/* just wake_up unconditional now, various lc_chaged(),
|
|
* lc_put() in drbd_try_clear_on_disk_bm(). */
|
|
wake_up = 1;
|
|
}
|
|
spin_unlock_irqrestore(&mdev->al_lock, flags);
|
|
if (wake_up)
|
|
wake_up(&mdev->al_wait);
|
|
}
|
|
|
|
/*
|
|
* this is intended to set one request worth of data out of sync.
|
|
* affects at least 1 bit,
|
|
* and at most 1+DRBD_MAX_SEGMENT_SIZE/BM_BLOCK_SIZE bits.
|
|
*
|
|
* called by tl_clear and drbd_send_dblock (==drbd_make_request).
|
|
* so this can be _any_ process.
|
|
*/
|
|
void __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector, int size,
|
|
const char *file, const unsigned int line)
|
|
{
|
|
unsigned long sbnr, ebnr, lbnr, flags;
|
|
sector_t esector, nr_sectors;
|
|
unsigned int enr, count;
|
|
struct lc_element *e;
|
|
|
|
if (size <= 0 || (size & 0x1ff) != 0 || size > DRBD_MAX_SEGMENT_SIZE) {
|
|
dev_err(DEV, "sector: %llus, size: %d\n",
|
|
(unsigned long long)sector, size);
|
|
return;
|
|
}
|
|
|
|
if (!get_ldev(mdev))
|
|
return; /* no disk, no metadata, no bitmap to set bits in */
|
|
|
|
nr_sectors = drbd_get_capacity(mdev->this_bdev);
|
|
esector = sector + (size >> 9) - 1;
|
|
|
|
ERR_IF(sector >= nr_sectors)
|
|
goto out;
|
|
ERR_IF(esector >= nr_sectors)
|
|
esector = (nr_sectors-1);
|
|
|
|
lbnr = BM_SECT_TO_BIT(nr_sectors-1);
|
|
|
|
/* we set it out of sync,
|
|
* we do not need to round anything here */
|
|
sbnr = BM_SECT_TO_BIT(sector);
|
|
ebnr = BM_SECT_TO_BIT(esector);
|
|
|
|
/* ok, (capacity & 7) != 0 sometimes, but who cares...
|
|
* we count rs_{total,left} in bits, not sectors. */
|
|
spin_lock_irqsave(&mdev->al_lock, flags);
|
|
count = drbd_bm_set_bits(mdev, sbnr, ebnr);
|
|
|
|
enr = BM_SECT_TO_EXT(sector);
|
|
e = lc_find(mdev->resync, enr);
|
|
if (e)
|
|
lc_entry(e, struct bm_extent, lce)->rs_left += count;
|
|
spin_unlock_irqrestore(&mdev->al_lock, flags);
|
|
|
|
out:
|
|
put_ldev(mdev);
|
|
}
|
|
|
|
static
|
|
struct bm_extent *_bme_get(struct drbd_conf *mdev, unsigned int enr)
|
|
{
|
|
struct lc_element *e;
|
|
struct bm_extent *bm_ext;
|
|
int wakeup = 0;
|
|
unsigned long rs_flags;
|
|
|
|
spin_lock_irq(&mdev->al_lock);
|
|
if (mdev->resync_locked > mdev->resync->nr_elements/2) {
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
return NULL;
|
|
}
|
|
e = lc_get(mdev->resync, enr);
|
|
bm_ext = e ? lc_entry(e, struct bm_extent, lce) : NULL;
|
|
if (bm_ext) {
|
|
if (bm_ext->lce.lc_number != enr) {
|
|
bm_ext->rs_left = drbd_bm_e_weight(mdev, enr);
|
|
bm_ext->rs_failed = 0;
|
|
lc_changed(mdev->resync, &bm_ext->lce);
|
|
wakeup = 1;
|
|
}
|
|
if (bm_ext->lce.refcnt == 1)
|
|
mdev->resync_locked++;
|
|
set_bit(BME_NO_WRITES, &bm_ext->flags);
|
|
}
|
|
rs_flags = mdev->resync->flags;
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
if (wakeup)
|
|
wake_up(&mdev->al_wait);
|
|
|
|
if (!bm_ext) {
|
|
if (rs_flags & LC_STARVING)
|
|
dev_warn(DEV, "Have to wait for element"
|
|
" (resync LRU too small?)\n");
|
|
BUG_ON(rs_flags & LC_DIRTY);
|
|
}
|
|
|
|
return bm_ext;
|
|
}
|
|
|
|
static int _is_in_al(struct drbd_conf *mdev, unsigned int enr)
|
|
{
|
|
struct lc_element *al_ext;
|
|
int rv = 0;
|
|
|
|
spin_lock_irq(&mdev->al_lock);
|
|
if (unlikely(enr == mdev->act_log->new_number))
|
|
rv = 1;
|
|
else {
|
|
al_ext = lc_find(mdev->act_log, enr);
|
|
if (al_ext) {
|
|
if (al_ext->refcnt)
|
|
rv = 1;
|
|
}
|
|
}
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
|
|
/*
|
|
if (unlikely(rv)) {
|
|
dev_info(DEV, "Delaying sync read until app's write is done\n");
|
|
}
|
|
*/
|
|
return rv;
|
|
}
|
|
|
|
/**
|
|
* drbd_rs_begin_io() - Gets an extent in the resync LRU cache and sets it to BME_LOCKED
|
|
* @mdev: DRBD device.
|
|
* @sector: The sector number.
|
|
*
|
|
* This functions sleeps on al_wait. Returns 1 on success, 0 if interrupted.
|
|
*/
|
|
int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector)
|
|
{
|
|
unsigned int enr = BM_SECT_TO_EXT(sector);
|
|
struct bm_extent *bm_ext;
|
|
int i, sig;
|
|
|
|
sig = wait_event_interruptible(mdev->al_wait,
|
|
(bm_ext = _bme_get(mdev, enr)));
|
|
if (sig)
|
|
return 0;
|
|
|
|
if (test_bit(BME_LOCKED, &bm_ext->flags))
|
|
return 1;
|
|
|
|
for (i = 0; i < AL_EXT_PER_BM_SECT; i++) {
|
|
sig = wait_event_interruptible(mdev->al_wait,
|
|
!_is_in_al(mdev, enr * AL_EXT_PER_BM_SECT + i));
|
|
if (sig) {
|
|
spin_lock_irq(&mdev->al_lock);
|
|
if (lc_put(mdev->resync, &bm_ext->lce) == 0) {
|
|
clear_bit(BME_NO_WRITES, &bm_ext->flags);
|
|
mdev->resync_locked--;
|
|
wake_up(&mdev->al_wait);
|
|
}
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
set_bit(BME_LOCKED, &bm_ext->flags);
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* drbd_try_rs_begin_io() - Gets an extent in the resync LRU cache, does not sleep
|
|
* @mdev: DRBD device.
|
|
* @sector: The sector number.
|
|
*
|
|
* Gets an extent in the resync LRU cache, sets it to BME_NO_WRITES, then
|
|
* tries to set it to BME_LOCKED. Returns 0 upon success, and -EAGAIN
|
|
* if there is still application IO going on in this area.
|
|
*/
|
|
int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector)
|
|
{
|
|
unsigned int enr = BM_SECT_TO_EXT(sector);
|
|
const unsigned int al_enr = enr*AL_EXT_PER_BM_SECT;
|
|
struct lc_element *e;
|
|
struct bm_extent *bm_ext;
|
|
int i;
|
|
|
|
spin_lock_irq(&mdev->al_lock);
|
|
if (mdev->resync_wenr != LC_FREE && mdev->resync_wenr != enr) {
|
|
/* in case you have very heavy scattered io, it may
|
|
* stall the syncer undefined if we give up the ref count
|
|
* when we try again and requeue.
|
|
*
|
|
* if we don't give up the refcount, but the next time
|
|
* we are scheduled this extent has been "synced" by new
|
|
* application writes, we'd miss the lc_put on the
|
|
* extent we keep the refcount on.
|
|
* so we remembered which extent we had to try again, and
|
|
* if the next requested one is something else, we do
|
|
* the lc_put here...
|
|
* we also have to wake_up
|
|
*/
|
|
e = lc_find(mdev->resync, mdev->resync_wenr);
|
|
bm_ext = e ? lc_entry(e, struct bm_extent, lce) : NULL;
|
|
if (bm_ext) {
|
|
D_ASSERT(!test_bit(BME_LOCKED, &bm_ext->flags));
|
|
D_ASSERT(test_bit(BME_NO_WRITES, &bm_ext->flags));
|
|
clear_bit(BME_NO_WRITES, &bm_ext->flags);
|
|
mdev->resync_wenr = LC_FREE;
|
|
if (lc_put(mdev->resync, &bm_ext->lce) == 0)
|
|
mdev->resync_locked--;
|
|
wake_up(&mdev->al_wait);
|
|
} else {
|
|
dev_alert(DEV, "LOGIC BUG\n");
|
|
}
|
|
}
|
|
/* TRY. */
|
|
e = lc_try_get(mdev->resync, enr);
|
|
bm_ext = e ? lc_entry(e, struct bm_extent, lce) : NULL;
|
|
if (bm_ext) {
|
|
if (test_bit(BME_LOCKED, &bm_ext->flags))
|
|
goto proceed;
|
|
if (!test_and_set_bit(BME_NO_WRITES, &bm_ext->flags)) {
|
|
mdev->resync_locked++;
|
|
} else {
|
|
/* we did set the BME_NO_WRITES,
|
|
* but then could not set BME_LOCKED,
|
|
* so we tried again.
|
|
* drop the extra reference. */
|
|
bm_ext->lce.refcnt--;
|
|
D_ASSERT(bm_ext->lce.refcnt > 0);
|
|
}
|
|
goto check_al;
|
|
} else {
|
|
/* do we rather want to try later? */
|
|
if (mdev->resync_locked > mdev->resync->nr_elements-3)
|
|
goto try_again;
|
|
/* Do or do not. There is no try. -- Yoda */
|
|
e = lc_get(mdev->resync, enr);
|
|
bm_ext = e ? lc_entry(e, struct bm_extent, lce) : NULL;
|
|
if (!bm_ext) {
|
|
const unsigned long rs_flags = mdev->resync->flags;
|
|
if (rs_flags & LC_STARVING)
|
|
dev_warn(DEV, "Have to wait for element"
|
|
" (resync LRU too small?)\n");
|
|
BUG_ON(rs_flags & LC_DIRTY);
|
|
goto try_again;
|
|
}
|
|
if (bm_ext->lce.lc_number != enr) {
|
|
bm_ext->rs_left = drbd_bm_e_weight(mdev, enr);
|
|
bm_ext->rs_failed = 0;
|
|
lc_changed(mdev->resync, &bm_ext->lce);
|
|
wake_up(&mdev->al_wait);
|
|
D_ASSERT(test_bit(BME_LOCKED, &bm_ext->flags) == 0);
|
|
}
|
|
set_bit(BME_NO_WRITES, &bm_ext->flags);
|
|
D_ASSERT(bm_ext->lce.refcnt == 1);
|
|
mdev->resync_locked++;
|
|
goto check_al;
|
|
}
|
|
check_al:
|
|
for (i = 0; i < AL_EXT_PER_BM_SECT; i++) {
|
|
if (unlikely(al_enr+i == mdev->act_log->new_number))
|
|
goto try_again;
|
|
if (lc_is_used(mdev->act_log, al_enr+i))
|
|
goto try_again;
|
|
}
|
|
set_bit(BME_LOCKED, &bm_ext->flags);
|
|
proceed:
|
|
mdev->resync_wenr = LC_FREE;
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
return 0;
|
|
|
|
try_again:
|
|
if (bm_ext)
|
|
mdev->resync_wenr = enr;
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector)
|
|
{
|
|
unsigned int enr = BM_SECT_TO_EXT(sector);
|
|
struct lc_element *e;
|
|
struct bm_extent *bm_ext;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&mdev->al_lock, flags);
|
|
e = lc_find(mdev->resync, enr);
|
|
bm_ext = e ? lc_entry(e, struct bm_extent, lce) : NULL;
|
|
if (!bm_ext) {
|
|
spin_unlock_irqrestore(&mdev->al_lock, flags);
|
|
if (__ratelimit(&drbd_ratelimit_state))
|
|
dev_err(DEV, "drbd_rs_complete_io() called, but extent not found\n");
|
|
return;
|
|
}
|
|
|
|
if (bm_ext->lce.refcnt == 0) {
|
|
spin_unlock_irqrestore(&mdev->al_lock, flags);
|
|
dev_err(DEV, "drbd_rs_complete_io(,%llu [=%u]) called, "
|
|
"but refcnt is 0!?\n",
|
|
(unsigned long long)sector, enr);
|
|
return;
|
|
}
|
|
|
|
if (lc_put(mdev->resync, &bm_ext->lce) == 0) {
|
|
clear_bit(BME_LOCKED, &bm_ext->flags);
|
|
clear_bit(BME_NO_WRITES, &bm_ext->flags);
|
|
mdev->resync_locked--;
|
|
wake_up(&mdev->al_wait);
|
|
}
|
|
|
|
spin_unlock_irqrestore(&mdev->al_lock, flags);
|
|
}
|
|
|
|
/**
|
|
* drbd_rs_cancel_all() - Removes all extents from the resync LRU (even BME_LOCKED)
|
|
* @mdev: DRBD device.
|
|
*/
|
|
void drbd_rs_cancel_all(struct drbd_conf *mdev)
|
|
{
|
|
spin_lock_irq(&mdev->al_lock);
|
|
|
|
if (get_ldev_if_state(mdev, D_FAILED)) { /* Makes sure ->resync is there. */
|
|
lc_reset(mdev->resync);
|
|
put_ldev(mdev);
|
|
}
|
|
mdev->resync_locked = 0;
|
|
mdev->resync_wenr = LC_FREE;
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
wake_up(&mdev->al_wait);
|
|
}
|
|
|
|
/**
|
|
* drbd_rs_del_all() - Gracefully remove all extents from the resync LRU
|
|
* @mdev: DRBD device.
|
|
*
|
|
* Returns 0 upon success, -EAGAIN if at least one reference count was
|
|
* not zero.
|
|
*/
|
|
int drbd_rs_del_all(struct drbd_conf *mdev)
|
|
{
|
|
struct lc_element *e;
|
|
struct bm_extent *bm_ext;
|
|
int i;
|
|
|
|
spin_lock_irq(&mdev->al_lock);
|
|
|
|
if (get_ldev_if_state(mdev, D_FAILED)) {
|
|
/* ok, ->resync is there. */
|
|
for (i = 0; i < mdev->resync->nr_elements; i++) {
|
|
e = lc_element_by_index(mdev->resync, i);
|
|
bm_ext = e ? lc_entry(e, struct bm_extent, lce) : NULL;
|
|
if (bm_ext->lce.lc_number == LC_FREE)
|
|
continue;
|
|
if (bm_ext->lce.lc_number == mdev->resync_wenr) {
|
|
dev_info(DEV, "dropping %u in drbd_rs_del_all, apparently"
|
|
" got 'synced' by application io\n",
|
|
mdev->resync_wenr);
|
|
D_ASSERT(!test_bit(BME_LOCKED, &bm_ext->flags));
|
|
D_ASSERT(test_bit(BME_NO_WRITES, &bm_ext->flags));
|
|
clear_bit(BME_NO_WRITES, &bm_ext->flags);
|
|
mdev->resync_wenr = LC_FREE;
|
|
lc_put(mdev->resync, &bm_ext->lce);
|
|
}
|
|
if (bm_ext->lce.refcnt != 0) {
|
|
dev_info(DEV, "Retrying drbd_rs_del_all() later. "
|
|
"refcnt=%d\n", bm_ext->lce.refcnt);
|
|
put_ldev(mdev);
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
return -EAGAIN;
|
|
}
|
|
D_ASSERT(!test_bit(BME_LOCKED, &bm_ext->flags));
|
|
D_ASSERT(!test_bit(BME_NO_WRITES, &bm_ext->flags));
|
|
lc_del(mdev->resync, &bm_ext->lce);
|
|
}
|
|
D_ASSERT(mdev->resync->used == 0);
|
|
put_ldev(mdev);
|
|
}
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* drbd_rs_failed_io() - Record information on a failure to resync the specified blocks
|
|
* @mdev: DRBD device.
|
|
* @sector: The sector number.
|
|
* @size: Size of failed IO operation, in byte.
|
|
*/
|
|
void drbd_rs_failed_io(struct drbd_conf *mdev, sector_t sector, int size)
|
|
{
|
|
/* Is called from worker and receiver context _only_ */
|
|
unsigned long sbnr, ebnr, lbnr;
|
|
unsigned long count;
|
|
sector_t esector, nr_sectors;
|
|
int wake_up = 0;
|
|
|
|
if (size <= 0 || (size & 0x1ff) != 0 || size > DRBD_MAX_SEGMENT_SIZE) {
|
|
dev_err(DEV, "drbd_rs_failed_io: sector=%llus size=%d nonsense!\n",
|
|
(unsigned long long)sector, size);
|
|
return;
|
|
}
|
|
nr_sectors = drbd_get_capacity(mdev->this_bdev);
|
|
esector = sector + (size >> 9) - 1;
|
|
|
|
ERR_IF(sector >= nr_sectors) return;
|
|
ERR_IF(esector >= nr_sectors) esector = (nr_sectors-1);
|
|
|
|
lbnr = BM_SECT_TO_BIT(nr_sectors-1);
|
|
|
|
/*
|
|
* round up start sector, round down end sector. we make sure we only
|
|
* handle full, aligned, BM_BLOCK_SIZE (4K) blocks */
|
|
if (unlikely(esector < BM_SECT_PER_BIT-1))
|
|
return;
|
|
if (unlikely(esector == (nr_sectors-1)))
|
|
ebnr = lbnr;
|
|
else
|
|
ebnr = BM_SECT_TO_BIT(esector - (BM_SECT_PER_BIT-1));
|
|
sbnr = BM_SECT_TO_BIT(sector + BM_SECT_PER_BIT-1);
|
|
|
|
if (sbnr > ebnr)
|
|
return;
|
|
|
|
/*
|
|
* ok, (capacity & 7) != 0 sometimes, but who cares...
|
|
* we count rs_{total,left} in bits, not sectors.
|
|
*/
|
|
spin_lock_irq(&mdev->al_lock);
|
|
count = drbd_bm_count_bits(mdev, sbnr, ebnr);
|
|
if (count) {
|
|
mdev->rs_failed += count;
|
|
|
|
if (get_ldev(mdev)) {
|
|
drbd_try_clear_on_disk_bm(mdev, sector, count, FALSE);
|
|
put_ldev(mdev);
|
|
}
|
|
|
|
/* just wake_up unconditional now, various lc_chaged(),
|
|
* lc_put() in drbd_try_clear_on_disk_bm(). */
|
|
wake_up = 1;
|
|
}
|
|
spin_unlock_irq(&mdev->al_lock);
|
|
if (wake_up)
|
|
wake_up(&mdev->al_wait);
|
|
}
|