From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/fs/gfs2/meta_io.c | 403 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 403 insertions(+) create mode 100644 kernel/fs/gfs2/meta_io.c (limited to 'kernel/fs/gfs2/meta_io.c') diff --git a/kernel/fs/gfs2/meta_io.c b/kernel/fs/gfs2/meta_io.c new file mode 100644 index 000000000..b984a6e19 --- /dev/null +++ b/kernel/fs/gfs2/meta_io.c @@ -0,0 +1,403 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License version 2. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "gfs2.h" +#include "incore.h" +#include "glock.h" +#include "glops.h" +#include "inode.h" +#include "log.h" +#include "lops.h" +#include "meta_io.h" +#include "rgrp.h" +#include "trans.h" +#include "util.h" +#include "trace_gfs2.h" + +static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc) +{ + struct buffer_head *bh, *head; + int nr_underway = 0; + int write_op = REQ_META | REQ_PRIO | + (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); + + BUG_ON(!PageLocked(page)); + BUG_ON(!page_has_buffers(page)); + + head = page_buffers(page); + bh = head; + + do { + if (!buffer_mapped(bh)) + continue; + /* + * If it's a fully non-blocking write attempt and we cannot + * lock the buffer then redirty the page. Note that this can + * potentially cause a busy-wait loop from flusher thread and kswapd + * activity, but those code paths have their own higher-level + * throttling. + */ + if (wbc->sync_mode != WB_SYNC_NONE) { + lock_buffer(bh); + } else if (!trylock_buffer(bh)) { + redirty_page_for_writepage(wbc, page); + continue; + } + if (test_clear_buffer_dirty(bh)) { + mark_buffer_async_write(bh); + } else { + unlock_buffer(bh); + } + } while ((bh = bh->b_this_page) != head); + + /* + * The page and its buffers are protected by PageWriteback(), so we can + * drop the bh refcounts early. + */ + BUG_ON(PageWriteback(page)); + set_page_writeback(page); + + do { + struct buffer_head *next = bh->b_this_page; + if (buffer_async_write(bh)) { + submit_bh(write_op, bh); + nr_underway++; + } + bh = next; + } while (bh != head); + unlock_page(page); + + if (nr_underway == 0) + end_page_writeback(page); + + return 0; +} + +const struct address_space_operations gfs2_meta_aops = { + .writepage = gfs2_aspace_writepage, + .releasepage = gfs2_releasepage, +}; + +const struct address_space_operations gfs2_rgrp_aops = { + .writepage = gfs2_aspace_writepage, + .releasepage = gfs2_releasepage, +}; + +/** + * gfs2_getbuf - Get a buffer with a given address space + * @gl: the glock + * @blkno: the block number (filesystem scope) + * @create: 1 if the buffer should be created + * + * Returns: the buffer + */ + +struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create) +{ + struct address_space *mapping = gfs2_glock2aspace(gl); + struct gfs2_sbd *sdp = gl->gl_sbd; + struct page *page; + struct buffer_head *bh; + unsigned int shift; + unsigned long index; + unsigned int bufnum; + + if (mapping == NULL) + mapping = &sdp->sd_aspace; + + shift = PAGE_CACHE_SHIFT - sdp->sd_sb.sb_bsize_shift; + index = blkno >> shift; /* convert block to page */ + bufnum = blkno - (index << shift); /* block buf index within page */ + + if (create) { + for (;;) { + page = grab_cache_page(mapping, index); + if (page) + break; + yield(); + } + } else { + page = find_get_page_flags(mapping, index, + FGP_LOCK|FGP_ACCESSED); + if (!page) + return NULL; + } + + if (!page_has_buffers(page)) + create_empty_buffers(page, sdp->sd_sb.sb_bsize, 0); + + /* Locate header for our buffer within our page */ + for (bh = page_buffers(page); bufnum--; bh = bh->b_this_page) + /* Do nothing */; + get_bh(bh); + + if (!buffer_mapped(bh)) + map_bh(bh, sdp->sd_vfs, blkno); + + unlock_page(page); + page_cache_release(page); + + return bh; +} + +static void meta_prep_new(struct buffer_head *bh) +{ + struct gfs2_meta_header *mh = (struct gfs2_meta_header *)bh->b_data; + + lock_buffer(bh); + clear_buffer_dirty(bh); + set_buffer_uptodate(bh); + unlock_buffer(bh); + + mh->mh_magic = cpu_to_be32(GFS2_MAGIC); +} + +/** + * gfs2_meta_new - Get a block + * @gl: The glock associated with this block + * @blkno: The block number + * + * Returns: The buffer + */ + +struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno) +{ + struct buffer_head *bh; + bh = gfs2_getbuf(gl, blkno, CREATE); + meta_prep_new(bh); + return bh; +} + +/** + * gfs2_meta_read - Read a block from disk + * @gl: The glock covering the block + * @blkno: The block number + * @flags: flags + * @bhp: the place where the buffer is returned (NULL on failure) + * + * Returns: errno + */ + +int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags, + struct buffer_head **bhp) +{ + struct gfs2_sbd *sdp = gl->gl_sbd; + struct buffer_head *bh; + + if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { + *bhp = NULL; + return -EIO; + } + + *bhp = bh = gfs2_getbuf(gl, blkno, CREATE); + + lock_buffer(bh); + if (buffer_uptodate(bh)) { + unlock_buffer(bh); + return 0; + } + bh->b_end_io = end_buffer_read_sync; + get_bh(bh); + submit_bh(READ_SYNC | REQ_META | REQ_PRIO, bh); + if (!(flags & DIO_WAIT)) + return 0; + + wait_on_buffer(bh); + if (unlikely(!buffer_uptodate(bh))) { + struct gfs2_trans *tr = current->journal_info; + if (tr && tr->tr_touched) + gfs2_io_error_bh(sdp, bh); + brelse(bh); + *bhp = NULL; + return -EIO; + } + + return 0; +} + +/** + * gfs2_meta_wait - Reread a block from disk + * @sdp: the filesystem + * @bh: The block to wait for + * + * Returns: errno + */ + +int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh) +{ + if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) + return -EIO; + + wait_on_buffer(bh); + + if (!buffer_uptodate(bh)) { + struct gfs2_trans *tr = current->journal_info; + if (tr && tr->tr_touched) + gfs2_io_error_bh(sdp, bh); + return -EIO; + } + if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) + return -EIO; + + return 0; +} + +void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr, int meta) +{ + struct address_space *mapping = bh->b_page->mapping; + struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping); + struct gfs2_bufdata *bd = bh->b_private; + int was_pinned = 0; + + if (test_clear_buffer_pinned(bh)) { + trace_gfs2_pin(bd, 0); + atomic_dec(&sdp->sd_log_pinned); + list_del_init(&bd->bd_list); + if (meta) + tr->tr_num_buf_rm++; + else + tr->tr_num_databuf_rm++; + tr->tr_touched = 1; + was_pinned = 1; + brelse(bh); + } + if (bd) { + spin_lock(&sdp->sd_ail_lock); + if (bd->bd_tr) { + gfs2_trans_add_revoke(sdp, bd); + } else if (was_pinned) { + bh->b_private = NULL; + kmem_cache_free(gfs2_bufdata_cachep, bd); + } + spin_unlock(&sdp->sd_ail_lock); + } + clear_buffer_dirty(bh); + clear_buffer_uptodate(bh); +} + +/** + * gfs2_meta_wipe - make inode's buffers so they aren't dirty/pinned anymore + * @ip: the inode who owns the buffers + * @bstart: the first buffer in the run + * @blen: the number of buffers in the run + * + */ + +void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + struct buffer_head *bh; + + while (blen) { + bh = gfs2_getbuf(ip->i_gl, bstart, NO_CREATE); + if (bh) { + lock_buffer(bh); + gfs2_log_lock(sdp); + gfs2_remove_from_journal(bh, current->journal_info, 1); + gfs2_log_unlock(sdp); + unlock_buffer(bh); + brelse(bh); + } + + bstart++; + blen--; + } +} + +/** + * gfs2_meta_indirect_buffer - Get a metadata buffer + * @ip: The GFS2 inode + * @height: The level of this buf in the metadata (indir addr) tree (if any) + * @num: The block number (device relative) of the buffer + * @bhp: the buffer is returned here + * + * Returns: errno + */ + +int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num, + struct buffer_head **bhp) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + struct gfs2_glock *gl = ip->i_gl; + struct buffer_head *bh; + int ret = 0; + u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI; + + ret = gfs2_meta_read(gl, num, DIO_WAIT, &bh); + if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) { + brelse(bh); + ret = -EIO; + } + *bhp = bh; + return ret; +} + +/** + * gfs2_meta_ra - start readahead on an extent of a file + * @gl: the glock the blocks belong to + * @dblock: the starting disk block + * @extlen: the number of blocks in the extent + * + * returns: the first buffer in the extent + */ + +struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen) +{ + struct gfs2_sbd *sdp = gl->gl_sbd; + struct buffer_head *first_bh, *bh; + u32 max_ra = gfs2_tune_get(sdp, gt_max_readahead) >> + sdp->sd_sb.sb_bsize_shift; + + BUG_ON(!extlen); + + if (max_ra < 1) + max_ra = 1; + if (extlen > max_ra) + extlen = max_ra; + + first_bh = gfs2_getbuf(gl, dblock, CREATE); + + if (buffer_uptodate(first_bh)) + goto out; + if (!buffer_locked(first_bh)) + ll_rw_block(READ_SYNC | REQ_META, 1, &first_bh); + + dblock++; + extlen--; + + while (extlen) { + bh = gfs2_getbuf(gl, dblock, CREATE); + + if (!buffer_uptodate(bh) && !buffer_locked(bh)) + ll_rw_block(READA | REQ_META, 1, &bh); + brelse(bh); + dblock++; + extlen--; + if (!buffer_locked(first_bh) && buffer_uptodate(first_bh)) + goto out; + } + + wait_on_buffer(first_bh); +out: + return first_bh; +} + -- cgit 1.2.3-korg