/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- * vim:expandtab:shiftwidth=8:tabstop=8: * * linux/fs/obdfilter/filter_io.c * * Copyright (c) 2001-2003 Cluster File Systems, Inc. * Author: Peter Braam * Author: Andreas Dilger * Author: Phil Schwan * * This file is part of Lustre, http://www.lustre.org. * * Lustre is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * Lustre is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Lustre; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include // XXX kill me soon #include #include #define DEBUG_SUBSYSTEM S_FILTER #include #include #include "filter_internal.h" /* 512byte block min */ #define MAX_BLOCKS_PER_PAGE (PAGE_SIZE / 512) struct dio_request { atomic_t dr_numreqs; /* number of reqs being processed */ struct bio *dr_bios; /* list of completed bios */ wait_queue_head_t dr_wait; int dr_max_pages; int dr_npages; int dr_error; struct page **dr_pages; unsigned long *dr_blocks; spinlock_t dr_lock; }; static int dio_complete_routine(struct bio *bio, unsigned int done, int error) { struct dio_request *dreq = bio->bi_private; unsigned long flags; if (bio->bi_size) { CWARN("gets called against non-complete bio 0x%p: %d/%d/%d\n", bio, bio->bi_size, done, error); return 1; } if (dreq == NULL) { CERROR("***** bio->bi_private is NULL! This should never " "happen. Normally, I would crash here, but instead I " "will dump the bio contents to the console. Please " "report this to CFS, along with any interesting messages " "leading up to this point (like SCSI errors, perhaps). " "Because bi_private is NULL, I can't wake up the thread " "that initiated this I/O -- so you will probably have to " "reboot this node."); CERROR("bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d, " "bi_idx: %d, bi->size: %d, bi_end_io: %p, bi_cnt: %d, " "bi_private: %p\n", bio->bi_next, bio->bi_flags, bio->bi_rw, bio->bi_vcnt, bio->bi_idx, bio->bi_size, bio->bi_end_io, atomic_read(&bio->bi_cnt), bio->bi_private); return 0; } spin_lock_irqsave(&dreq->dr_lock, flags); bio->bi_private = dreq->dr_bios; dreq->dr_bios = bio; if (dreq->dr_error == 0) dreq->dr_error = error; spin_unlock_irqrestore(&dreq->dr_lock, flags); if (atomic_dec_and_test(&dreq->dr_numreqs)) wake_up(&dreq->dr_wait); return 0; } static int can_be_merged(struct bio *bio, sector_t sector) { unsigned int size; if (!bio) return 0; size = bio->bi_size >> 9; return bio->bi_sector + size == sector ? 1 : 0; } int filter_alloc_iobuf(int rw, int num_pages, void **ret) { struct dio_request *dreq; LASSERTF(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ, "%x\n", rw); OBD_ALLOC(dreq, sizeof(*dreq)); if (dreq == NULL) goto failed_0; OBD_ALLOC(dreq->dr_pages, num_pages * sizeof(*dreq->dr_pages)); if (dreq->dr_pages == NULL) goto failed_1; OBD_ALLOC(dreq->dr_blocks, MAX_BLOCKS_PER_PAGE * num_pages * sizeof(*dreq->dr_blocks)); if (dreq->dr_blocks == NULL) goto failed_2; dreq->dr_bios = NULL; init_waitqueue_head(&dreq->dr_wait); atomic_set(&dreq->dr_numreqs, 0); spin_lock_init(&dreq->dr_lock); dreq->dr_max_pages = num_pages; dreq->dr_npages = 0; *ret = dreq; RETURN(0); failed_2: OBD_FREE(dreq->dr_pages, num_pages * sizeof(*dreq->dr_pages)); failed_1: OBD_FREE(dreq, sizeof(*dreq)); failed_0: RETURN(-ENOMEM); } void filter_free_iobuf(void *iobuf) { struct dio_request *dreq = iobuf; int num_pages = dreq->dr_max_pages; /* free all bios */ while (dreq->dr_bios) { struct bio *bio = dreq->dr_bios; dreq->dr_bios = bio->bi_private; bio_put(bio); } OBD_FREE(dreq->dr_blocks, MAX_BLOCKS_PER_PAGE * num_pages * sizeof(*dreq->dr_blocks)); OBD_FREE(dreq->dr_pages, num_pages * sizeof(*dreq->dr_pages)); OBD_FREE(dreq, sizeof(*dreq)); } int filter_iobuf_add_page(struct obd_device *obd, void *iobuf, struct inode *inode, struct page *page) { struct dio_request *dreq = iobuf; LASSERT (dreq->dr_npages < dreq->dr_max_pages); dreq->dr_pages[dreq->dr_npages++] = page; return 0; } int filter_do_bio(struct obd_device *obd, struct inode *inode, struct dio_request *dreq, int rw) { int blocks_per_page = PAGE_SIZE >> inode->i_blkbits; struct page **pages = dreq->dr_pages; int npages = dreq->dr_npages; unsigned long *blocks = dreq->dr_blocks; int total_blocks = npages * blocks_per_page; int sector_bits = inode->i_sb->s_blocksize_bits - 9; unsigned int blocksize = inode->i_sb->s_blocksize; struct bio *bio = NULL; struct page *page; unsigned int page_offset; sector_t sector; int nblocks; int block_idx; int page_idx; int i; int rc = 0; ENTRY; LASSERT(dreq->dr_npages == npages); LASSERT(total_blocks <= OBDFILTER_CREATED_SCRATCHPAD_ENTRIES); for (page_idx = 0, block_idx = 0; page_idx < npages; page_idx++, block_idx += blocks_per_page) { page = pages[page_idx]; LASSERT (block_idx + blocks_per_page <= total_blocks); for (i = 0, page_offset = 0; i < blocks_per_page; i += nblocks, page_offset += blocksize * nblocks) { nblocks = 1; if (blocks[block_idx + i] == 0) { /* hole */ LASSERT(rw == OBD_BRW_READ); memset(kmap(page) + page_offset, 0, blocksize); kunmap(page); continue; } sector = blocks[block_idx + i] << sector_bits; /* Additional contiguous file blocks? */ while (i + nblocks < blocks_per_page && (sector + nblocks*(blocksize>>9)) == (blocks[block_idx + i + nblocks] << sector_bits)) nblocks++; if (bio != NULL && can_be_merged(bio, sector) && bio_add_page(bio, page, blocksize * nblocks, page_offset) != 0) continue; /* added this frag OK */ if (bio != NULL) { request_queue_t *q = bdev_get_queue(bio->bi_bdev); /* Dang! I have to fragment this I/O */ CDEBUG(D_INODE, "bio++ sz %d vcnt %d(%d) " "sectors %d(%d) psg %d(%d) hsg %d(%d)\n", bio->bi_size, bio->bi_vcnt, bio->bi_max_vecs, bio->bi_size >> 9, q->max_sectors, bio_phys_segments(q, bio), q->max_phys_segments, bio_hw_segments(q, bio), q->max_hw_segments); atomic_inc(&dreq->dr_numreqs); rc = fsfilt_send_bio(rw, obd, inode, bio); if (rc < 0) { CERROR("Can't send bio: %d\n", rc); /* OK do dec; we do the waiting */ atomic_dec(&dreq->dr_numreqs); goto out; } rc = 0; bio = NULL; } /* allocate new bio */ bio = bio_alloc(GFP_NOIO, (npages - page_idx) * blocks_per_page); if (bio == NULL) { CERROR ("Can't allocate bio\n"); rc = -ENOMEM; goto out; } bio->bi_bdev = inode->i_sb->s_bdev; bio->bi_sector = sector; bio->bi_end_io = dio_complete_routine; bio->bi_private = dreq; rc = bio_add_page(bio, page, blocksize * nblocks, page_offset); LASSERT (rc != 0); } } if (bio != NULL) { atomic_inc(&dreq->dr_numreqs); rc = fsfilt_send_bio(rw, obd, inode, bio); if (rc >= 0) { rc = 0; } else { CERROR("Can't send bio: %d\n", rc); /* OK do dec; we do the waiting */ atomic_dec(&dreq->dr_numreqs); } } out: wait_event(dreq->dr_wait, atomic_read(&dreq->dr_numreqs) == 0); if (rc == 0) rc = dreq->dr_error; RETURN(rc); } /* These are our hacks to keep our directio/bh IO coherent with ext3's * page cache use. Most notably ext3 reads file data into the page * cache when it is zeroing the tail of partial-block truncates and * leaves it there, sometimes generating io from it at later truncates. * This removes the partial page and its buffers from the page cache, * so it should only ever cause a wait in rare cases, as otherwise we * always do full-page IO to the OST. * * The call to truncate_complete_page() will call journal_invalidatepage() * to free the buffers and drop the page from cache. The buffers should * not be dirty, because we already called fdatasync/fdatawait on them. */ static int filter_clear_page_cache(struct inode *inode, struct dio_request *iobuf) { struct page *page; int i, rc, rc2; /* This is nearly generic_osync_inode, without the waiting on the inode rc = generic_osync_inode(inode, inode->i_mapping, OSYNC_DATA|OSYNC_METADATA); */ rc = filemap_fdatawrite(inode->i_mapping); rc2 = sync_mapping_buffers(inode->i_mapping); if (rc == 0) rc = rc2; rc2 = filemap_fdatawait(inode->i_mapping); if (rc == 0) rc = rc2; if (rc != 0) RETURN(rc); /* be careful to call this after fsync_inode_data_buffers has waited * for IO to complete before we evict it from the cache */ for (i = 0; i < iobuf->dr_npages; i++) { page = find_lock_page(inode->i_mapping, iobuf->dr_pages[i]->index); if (page == NULL) continue; if (page->mapping != NULL) { wait_on_page_writeback(page); ll_truncate_complete_page(page); } unlock_page(page); page_cache_release(page); } return 0; } /* Must be called with i_sem taken for writes; this will drop it */ int filter_direct_io(int rw, struct dentry *dchild, void *iobuf, struct obd_export *exp, struct iattr *attr, struct obd_trans_info *oti, void **wait_handle) { struct obd_device *obd = exp->exp_obd; struct inode *inode = dchild->d_inode; struct dio_request *dreq = iobuf; struct semaphore *sem = NULL; int rc, rc2, create = 0; ENTRY; LASSERTF(rw == OBD_BRW_WRITE || rw == OBD_BRW_READ, "%x\n", rw); LASSERTF(dreq->dr_npages <= dreq->dr_max_pages, "%d,%d\n", dreq->dr_npages, dreq->dr_max_pages); if (dreq->dr_npages == 0) RETURN(0); if (dreq->dr_npages > OBDFILTER_CREATED_SCRATCHPAD_ENTRIES) RETURN(-EINVAL); if (rw == OBD_BRW_WRITE) { create = 1; //sem = &obd->u.filter.fo_alloc_lock; } rc = fsfilt_map_inode_pages(obd, inode, dreq->dr_pages, dreq->dr_npages, dreq->dr_blocks, obdfilter_created_scratchpad, create, sem); if (rw == OBD_BRW_WRITE) { if (rc == 0) { int blocks_per_page = PAGE_SIZE >> inode->i_blkbits; filter_tally_write(&obd->u.filter, dreq->dr_pages, dreq->dr_npages, dreq->dr_blocks, blocks_per_page); if (attr->ia_size > inode->i_size) attr->ia_valid |= ATTR_SIZE; rc = fsfilt_setattr(obd, dchild, oti->oti_handle, attr, 0); } up(&inode->i_sem); rc2 = filter_finish_transno(exp, oti, 0); if (rc2 != 0) CERROR("can't close transaction: %d\n", rc); rc = (rc == 0) ? rc2 : rc; rc2 = fsfilt_commit_async(obd,inode,oti->oti_handle,wait_handle); rc = (rc == 0) ? rc2 : rc; if (rc != 0) RETURN(rc); } rc = filter_clear_page_cache(inode, dreq); if (rc != 0) RETURN(rc); RETURN(filter_do_bio(obd, inode, dreq, rw)); } /* See if there are unallocated parts in given file region */ static int filter_range_is_mapped(struct inode *inode, obd_size offset, int len) { sector_t (*fs_bmap)(struct address_space *, sector_t) = inode->i_mapping->a_ops->bmap; int j; /* We can't know if we are overwriting or not */ if (fs_bmap == NULL) return 0; offset >>= inode->i_blkbits; len >>= inode->i_blkbits; for (j = 0; j <= len; j++) if (fs_bmap(inode->i_mapping, offset + j) == 0) return 0; return 1; } int filter_commitrw_write(struct obd_export *exp, struct obdo *oa, int objcount, struct obd_ioobj *obj, int niocount, struct niobuf_local *res, struct obd_trans_info *oti, int rc) { struct niobuf_local *lnb; struct dio_request *dreq = NULL; struct lvfs_run_ctxt saved; struct fsfilt_objinfo fso; struct iattr iattr = { 0 }; struct inode *inode = NULL; unsigned long now = jiffies; int i, err, cleanup_phase = 0; struct obd_device *obd = exp->exp_obd; void *wait_handle = NULL; int total_size = 0; loff_t old_size; ENTRY; LASSERT(oti != NULL); LASSERT(objcount == 1); LASSERT(current->journal_info == NULL); if (rc != 0) GOTO(cleanup, rc); rc = filter_alloc_iobuf(OBD_BRW_WRITE, obj->ioo_bufcnt, (void **)&dreq); if (rc) GOTO(cleanup, rc); cleanup_phase = 1; fso.fso_dentry = res->dentry; fso.fso_bufcnt = obj->ioo_bufcnt; inode = res->dentry->d_inode; for (i = 0, lnb = res; i < obj->ioo_bufcnt; i++, lnb++) { loff_t this_size; /* If overwriting an existing block, we don't need a grant */ if (!(lnb->flags & OBD_BRW_GRANTED) && lnb->rc == -ENOSPC && filter_range_is_mapped(inode, lnb->offset, lnb->len)) lnb->rc = 0; if (lnb->rc) { /* ENOSPC, network RPC error, etc. */ CDEBUG(D_INODE, "Skipping [%d] == %d\n", i, lnb->rc); continue; } err = filter_iobuf_add_page(obd, dreq, inode, lnb->page); LASSERT (err == 0); total_size += lnb->len; /* we expect these pages to be in offset order, but we'll * be forgiving */ this_size = lnb->offset + lnb->len; if (this_size > iattr.ia_size) iattr.ia_size = this_size; } #if 0 /* I use this when I'm checking our lovely 1M I/Os reach the disk -eeb */ if (total_size != (1<<20)) CWARN("total size %d (%d pages)\n", total_size, total_size/PAGE_SIZE); #endif push_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL); cleanup_phase = 2; down(&inode->i_sem); old_size = inode->i_size; oti->oti_handle = fsfilt_brw_start(obd, objcount, &fso, niocount, res, oti); if (IS_ERR(oti->oti_handle)) { up(&inode->i_sem); rc = PTR_ERR(oti->oti_handle); CDEBUG(rc == -ENOSPC ? D_INODE : D_ERROR, "error starting transaction: rc = %d\n", rc); oti->oti_handle = NULL; GOTO(cleanup, rc); } /* have to call fsfilt_commit() from this point on */ fsfilt_check_slow(now, obd_timeout, "brw_start"); iattr_from_obdo(&iattr,oa,OBD_MD_FLATIME|OBD_MD_FLMTIME|OBD_MD_FLCTIME); /* filter_direct_io drops i_sem */ rc = filter_direct_io(OBD_BRW_WRITE, res->dentry, dreq, exp, &iattr, oti, &wait_handle); #if 0 if (inode->i_size != old_size) { struct llog_cookie *cookie = obdo_logcookie(oa); struct lustre_id *id = obdo_id(oa); filter_log_sz_change(obd, id, oa->o_easize, cookie, inode); } #endif if (rc == 0) obdo_from_inode(oa, inode, FILTER_VALID_FLAGS); fsfilt_check_slow(now, obd_timeout, "direct_io"); err = fsfilt_commit_wait(obd, inode, wait_handle); if (rc == 0) rc = err; fsfilt_check_slow(now, obd_timeout, "commitrw commit"); cleanup: filter_grant_commit(exp, niocount, res); switch (cleanup_phase) { case 2: pop_ctxt(&saved, &obd->obd_lvfs_ctxt, NULL); LASSERT(current->journal_info == NULL); case 1: filter_free_iobuf(dreq); case 0: filter_free_dio_pages(objcount, obj, niocount, res); f_dput(res->dentry); } RETURN(rc); }