1361 lines
34 KiB
C
1361 lines
34 KiB
C
/*
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* Copyright (c) 2000-2005 Silicon Graphics, Inc. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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*
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* Further, this software is distributed without any warranty that it is
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* free of the rightful claim of any third person regarding infringement
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* or the like. Any license provided herein, whether implied or
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* otherwise, applies only to this software file. Patent licenses, if
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* any, provided herein do not apply to combinations of this program with
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* other software, or any other product whatsoever.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write the Free Software Foundation, Inc., 59
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* Temple Place - Suite 330, Boston MA 02111-1307, USA.
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*
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* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
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* Mountain View, CA 94043, or:
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*
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* http://www.sgi.com
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*
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* For further information regarding this notice, see:
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*
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* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
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*/
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#include "xfs.h"
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#include "xfs_bit.h"
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#include "xfs_log.h"
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#include "xfs_inum.h"
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#include "xfs_sb.h"
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#include "xfs_ag.h"
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#include "xfs_dir.h"
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#include "xfs_dir2.h"
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#include "xfs_trans.h"
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#include "xfs_dmapi.h"
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#include "xfs_mount.h"
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#include "xfs_bmap_btree.h"
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#include "xfs_alloc_btree.h"
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#include "xfs_ialloc_btree.h"
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#include "xfs_dir_sf.h"
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#include "xfs_dir2_sf.h"
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#include "xfs_attr_sf.h"
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#include "xfs_dinode.h"
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#include "xfs_inode.h"
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#include "xfs_alloc.h"
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#include "xfs_btree.h"
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#include "xfs_error.h"
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#include "xfs_rw.h"
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#include "xfs_iomap.h"
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#include <linux/mpage.h>
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#include <linux/writeback.h>
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STATIC void xfs_count_page_state(struct page *, int *, int *, int *);
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STATIC void xfs_convert_page(struct inode *, struct page *, xfs_iomap_t *,
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struct writeback_control *wbc, void *, int, int);
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#if defined(XFS_RW_TRACE)
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void
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xfs_page_trace(
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int tag,
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struct inode *inode,
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struct page *page,
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int mask)
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{
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xfs_inode_t *ip;
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bhv_desc_t *bdp;
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vnode_t *vp = LINVFS_GET_VP(inode);
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loff_t isize = i_size_read(inode);
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loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
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int delalloc = -1, unmapped = -1, unwritten = -1;
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if (page_has_buffers(page))
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xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
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bdp = vn_bhv_lookup(VN_BHV_HEAD(vp), &xfs_vnodeops);
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ip = XFS_BHVTOI(bdp);
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if (!ip->i_rwtrace)
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return;
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ktrace_enter(ip->i_rwtrace,
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(void *)((unsigned long)tag),
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(void *)ip,
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(void *)inode,
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(void *)page,
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(void *)((unsigned long)mask),
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(void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)),
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(void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)),
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(void *)((unsigned long)((isize >> 32) & 0xffffffff)),
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(void *)((unsigned long)(isize & 0xffffffff)),
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(void *)((unsigned long)((offset >> 32) & 0xffffffff)),
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(void *)((unsigned long)(offset & 0xffffffff)),
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(void *)((unsigned long)delalloc),
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(void *)((unsigned long)unmapped),
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(void *)((unsigned long)unwritten),
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(void *)NULL,
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(void *)NULL);
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}
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#else
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#define xfs_page_trace(tag, inode, page, mask)
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#endif
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/*
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* Schedule IO completion handling on a xfsdatad if this was
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* the final hold on this ioend.
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*/
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STATIC void
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xfs_finish_ioend(
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xfs_ioend_t *ioend)
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{
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if (atomic_dec_and_test(&ioend->io_remaining))
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queue_work(xfsdatad_workqueue, &ioend->io_work);
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}
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STATIC void
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xfs_destroy_ioend(
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xfs_ioend_t *ioend)
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{
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vn_iowake(ioend->io_vnode);
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mempool_free(ioend, xfs_ioend_pool);
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}
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/*
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* Issue transactions to convert a buffer range from unwritten
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* to written extents.
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*/
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STATIC void
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xfs_end_bio_unwritten(
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void *data)
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{
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xfs_ioend_t *ioend = data;
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vnode_t *vp = ioend->io_vnode;
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xfs_off_t offset = ioend->io_offset;
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size_t size = ioend->io_size;
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struct buffer_head *bh, *next;
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int error;
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if (ioend->io_uptodate)
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VOP_BMAP(vp, offset, size, BMAPI_UNWRITTEN, NULL, NULL, error);
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/* ioend->io_buffer_head is only non-NULL for buffered I/O */
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for (bh = ioend->io_buffer_head; bh; bh = next) {
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next = bh->b_private;
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bh->b_end_io = NULL;
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clear_buffer_unwritten(bh);
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end_buffer_async_write(bh, ioend->io_uptodate);
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}
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xfs_destroy_ioend(ioend);
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}
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/*
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* Allocate and initialise an IO completion structure.
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* We need to track unwritten extent write completion here initially.
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* We'll need to extend this for updating the ondisk inode size later
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* (vs. incore size).
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*/
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STATIC xfs_ioend_t *
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xfs_alloc_ioend(
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struct inode *inode)
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{
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xfs_ioend_t *ioend;
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ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS);
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/*
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* Set the count to 1 initially, which will prevent an I/O
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* completion callback from happening before we have started
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* all the I/O from calling the completion routine too early.
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*/
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atomic_set(&ioend->io_remaining, 1);
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ioend->io_uptodate = 1; /* cleared if any I/O fails */
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ioend->io_vnode = LINVFS_GET_VP(inode);
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ioend->io_buffer_head = NULL;
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atomic_inc(&ioend->io_vnode->v_iocount);
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ioend->io_offset = 0;
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ioend->io_size = 0;
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INIT_WORK(&ioend->io_work, xfs_end_bio_unwritten, ioend);
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return ioend;
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}
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void
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linvfs_unwritten_done(
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struct buffer_head *bh,
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int uptodate)
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{
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xfs_ioend_t *ioend = bh->b_private;
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static spinlock_t unwritten_done_lock = SPIN_LOCK_UNLOCKED;
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unsigned long flags;
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ASSERT(buffer_unwritten(bh));
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bh->b_end_io = NULL;
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if (!uptodate)
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ioend->io_uptodate = 0;
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/*
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* Deep magic here. We reuse b_private in the buffer_heads to build
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* a chain for completing the I/O from user context after we've issued
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* a transaction to convert the unwritten extent.
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*/
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spin_lock_irqsave(&unwritten_done_lock, flags);
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bh->b_private = ioend->io_buffer_head;
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ioend->io_buffer_head = bh;
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spin_unlock_irqrestore(&unwritten_done_lock, flags);
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xfs_finish_ioend(ioend);
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}
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STATIC int
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xfs_map_blocks(
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struct inode *inode,
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loff_t offset,
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ssize_t count,
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xfs_iomap_t *mapp,
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int flags)
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{
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vnode_t *vp = LINVFS_GET_VP(inode);
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int error, nmaps = 1;
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VOP_BMAP(vp, offset, count, flags, mapp, &nmaps, error);
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if (!error && (flags & (BMAPI_WRITE|BMAPI_ALLOCATE)))
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VMODIFY(vp);
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return -error;
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}
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/*
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* Finds the corresponding mapping in block @map array of the
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* given @offset within a @page.
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*/
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STATIC xfs_iomap_t *
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xfs_offset_to_map(
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struct page *page,
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xfs_iomap_t *iomapp,
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unsigned long offset)
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{
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loff_t full_offset; /* offset from start of file */
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ASSERT(offset < PAGE_CACHE_SIZE);
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full_offset = page->index; /* NB: using 64bit number */
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full_offset <<= PAGE_CACHE_SHIFT; /* offset from file start */
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full_offset += offset; /* offset from page start */
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if (full_offset < iomapp->iomap_offset)
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return NULL;
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if (iomapp->iomap_offset + (iomapp->iomap_bsize -1) >= full_offset)
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return iomapp;
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return NULL;
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}
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STATIC void
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xfs_map_at_offset(
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struct page *page,
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struct buffer_head *bh,
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unsigned long offset,
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int block_bits,
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xfs_iomap_t *iomapp)
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{
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xfs_daddr_t bn;
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loff_t delta;
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int sector_shift;
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ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));
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ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY));
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ASSERT(iomapp->iomap_bn != IOMAP_DADDR_NULL);
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delta = page->index;
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delta <<= PAGE_CACHE_SHIFT;
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delta += offset;
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delta -= iomapp->iomap_offset;
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delta >>= block_bits;
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sector_shift = block_bits - BBSHIFT;
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bn = iomapp->iomap_bn >> sector_shift;
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bn += delta;
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BUG_ON(!bn && !(iomapp->iomap_flags & IOMAP_REALTIME));
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ASSERT((bn << sector_shift) >= iomapp->iomap_bn);
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lock_buffer(bh);
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bh->b_blocknr = bn;
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bh->b_bdev = iomapp->iomap_target->pbr_bdev;
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set_buffer_mapped(bh);
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clear_buffer_delay(bh);
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}
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/*
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* Look for a page at index which is unlocked and contains our
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* unwritten extent flagged buffers at its head. Returns page
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* locked and with an extra reference count, and length of the
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* unwritten extent component on this page that we can write,
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* in units of filesystem blocks.
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*/
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STATIC struct page *
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xfs_probe_unwritten_page(
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struct address_space *mapping,
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pgoff_t index,
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xfs_iomap_t *iomapp,
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xfs_ioend_t *ioend,
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unsigned long max_offset,
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unsigned long *fsbs,
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unsigned int bbits)
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{
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struct page *page;
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page = find_trylock_page(mapping, index);
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if (!page)
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return NULL;
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if (PageWriteback(page))
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goto out;
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if (page->mapping && page_has_buffers(page)) {
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struct buffer_head *bh, *head;
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unsigned long p_offset = 0;
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*fsbs = 0;
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bh = head = page_buffers(page);
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do {
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if (!buffer_unwritten(bh) || !buffer_uptodate(bh))
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break;
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if (!xfs_offset_to_map(page, iomapp, p_offset))
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break;
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if (p_offset >= max_offset)
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break;
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xfs_map_at_offset(page, bh, p_offset, bbits, iomapp);
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set_buffer_unwritten_io(bh);
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bh->b_private = ioend;
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p_offset += bh->b_size;
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(*fsbs)++;
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} while ((bh = bh->b_this_page) != head);
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if (p_offset)
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return page;
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}
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out:
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unlock_page(page);
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return NULL;
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}
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/*
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* Look for a page at index which is unlocked and not mapped
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* yet - clustering for mmap write case.
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*/
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STATIC unsigned int
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xfs_probe_unmapped_page(
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struct address_space *mapping,
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pgoff_t index,
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unsigned int pg_offset)
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{
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struct page *page;
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int ret = 0;
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page = find_trylock_page(mapping, index);
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if (!page)
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return 0;
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if (PageWriteback(page))
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goto out;
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if (page->mapping && PageDirty(page)) {
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if (page_has_buffers(page)) {
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struct buffer_head *bh, *head;
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bh = head = page_buffers(page);
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do {
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if (buffer_mapped(bh) || !buffer_uptodate(bh))
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break;
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ret += bh->b_size;
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if (ret >= pg_offset)
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break;
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} while ((bh = bh->b_this_page) != head);
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} else
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ret = PAGE_CACHE_SIZE;
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}
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out:
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unlock_page(page);
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return ret;
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}
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STATIC unsigned int
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xfs_probe_unmapped_cluster(
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struct inode *inode,
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struct page *startpage,
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struct buffer_head *bh,
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struct buffer_head *head)
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{
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pgoff_t tindex, tlast, tloff;
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unsigned int pg_offset, len, total = 0;
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struct address_space *mapping = inode->i_mapping;
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/* First sum forwards in this page */
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do {
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if (buffer_mapped(bh))
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break;
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total += bh->b_size;
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} while ((bh = bh->b_this_page) != head);
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|
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/* If we reached the end of the page, sum forwards in
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* following pages.
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*/
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if (bh == head) {
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tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
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/* Prune this back to avoid pathological behavior */
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tloff = min(tlast, startpage->index + 64);
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for (tindex = startpage->index + 1; tindex < tloff; tindex++) {
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len = xfs_probe_unmapped_page(mapping, tindex,
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PAGE_CACHE_SIZE);
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if (!len)
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return total;
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total += len;
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}
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if (tindex == tlast &&
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(pg_offset = i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
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total += xfs_probe_unmapped_page(mapping,
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tindex, pg_offset);
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}
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}
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return total;
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}
|
|
|
|
/*
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* Probe for a given page (index) in the inode and test if it is delayed
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* and without unwritten buffers. Returns page locked and with an extra
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* reference count.
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*/
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STATIC struct page *
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xfs_probe_delalloc_page(
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struct inode *inode,
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pgoff_t index)
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{
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struct page *page;
|
|
|
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page = find_trylock_page(inode->i_mapping, index);
|
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if (!page)
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return NULL;
|
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if (PageWriteback(page))
|
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goto out;
|
|
|
|
if (page->mapping && page_has_buffers(page)) {
|
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struct buffer_head *bh, *head;
|
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int acceptable = 0;
|
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|
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bh = head = page_buffers(page);
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do {
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if (buffer_unwritten(bh)) {
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acceptable = 0;
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break;
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} else if (buffer_delay(bh)) {
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acceptable = 1;
|
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}
|
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} while ((bh = bh->b_this_page) != head);
|
|
|
|
if (acceptable)
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return page;
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|
}
|
|
|
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out:
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unlock_page(page);
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return NULL;
|
|
}
|
|
|
|
STATIC int
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|
xfs_map_unwritten(
|
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struct inode *inode,
|
|
struct page *start_page,
|
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struct buffer_head *head,
|
|
struct buffer_head *curr,
|
|
unsigned long p_offset,
|
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int block_bits,
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xfs_iomap_t *iomapp,
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struct writeback_control *wbc,
|
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int startio,
|
|
int all_bh)
|
|
{
|
|
struct buffer_head *bh = curr;
|
|
xfs_iomap_t *tmp;
|
|
xfs_ioend_t *ioend;
|
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loff_t offset;
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|
unsigned long nblocks = 0;
|
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|
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offset = start_page->index;
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offset <<= PAGE_CACHE_SHIFT;
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offset += p_offset;
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|
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ioend = xfs_alloc_ioend(inode);
|
|
|
|
/* First map forwards in the page consecutive buffers
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* covering this unwritten extent
|
|
*/
|
|
do {
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|
if (!buffer_unwritten(bh))
|
|
break;
|
|
tmp = xfs_offset_to_map(start_page, iomapp, p_offset);
|
|
if (!tmp)
|
|
break;
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|
xfs_map_at_offset(start_page, bh, p_offset, block_bits, iomapp);
|
|
set_buffer_unwritten_io(bh);
|
|
bh->b_private = ioend;
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|
p_offset += bh->b_size;
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nblocks++;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
|
|
atomic_add(nblocks, &ioend->io_remaining);
|
|
|
|
/* If we reached the end of the page, map forwards in any
|
|
* following pages which are also covered by this extent.
|
|
*/
|
|
if (bh == head) {
|
|
struct address_space *mapping = inode->i_mapping;
|
|
pgoff_t tindex, tloff, tlast;
|
|
unsigned long bs;
|
|
unsigned int pg_offset, bbits = inode->i_blkbits;
|
|
struct page *page;
|
|
|
|
tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
|
|
tloff = (iomapp->iomap_offset + iomapp->iomap_bsize) >> PAGE_CACHE_SHIFT;
|
|
tloff = min(tlast, tloff);
|
|
for (tindex = start_page->index + 1; tindex < tloff; tindex++) {
|
|
page = xfs_probe_unwritten_page(mapping,
|
|
tindex, iomapp, ioend,
|
|
PAGE_CACHE_SIZE, &bs, bbits);
|
|
if (!page)
|
|
break;
|
|
nblocks += bs;
|
|
atomic_add(bs, &ioend->io_remaining);
|
|
xfs_convert_page(inode, page, iomapp, wbc, ioend,
|
|
startio, all_bh);
|
|
/* stop if converting the next page might add
|
|
* enough blocks that the corresponding byte
|
|
* count won't fit in our ulong page buf length */
|
|
if (nblocks >= ((ULONG_MAX - PAGE_SIZE) >> block_bits))
|
|
goto enough;
|
|
}
|
|
|
|
if (tindex == tlast &&
|
|
(pg_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1)))) {
|
|
page = xfs_probe_unwritten_page(mapping,
|
|
tindex, iomapp, ioend,
|
|
pg_offset, &bs, bbits);
|
|
if (page) {
|
|
nblocks += bs;
|
|
atomic_add(bs, &ioend->io_remaining);
|
|
xfs_convert_page(inode, page, iomapp, wbc, ioend,
|
|
startio, all_bh);
|
|
if (nblocks >= ((ULONG_MAX - PAGE_SIZE) >> block_bits))
|
|
goto enough;
|
|
}
|
|
}
|
|
}
|
|
|
|
enough:
|
|
ioend->io_size = (xfs_off_t)nblocks << block_bits;
|
|
ioend->io_offset = offset;
|
|
xfs_finish_ioend(ioend);
|
|
return 0;
|
|
}
|
|
|
|
STATIC void
|
|
xfs_submit_page(
|
|
struct page *page,
|
|
struct writeback_control *wbc,
|
|
struct buffer_head *bh_arr[],
|
|
int bh_count,
|
|
int probed_page,
|
|
int clear_dirty)
|
|
{
|
|
struct buffer_head *bh;
|
|
int i;
|
|
|
|
BUG_ON(PageWriteback(page));
|
|
if (bh_count)
|
|
set_page_writeback(page);
|
|
if (clear_dirty)
|
|
clear_page_dirty(page);
|
|
unlock_page(page);
|
|
|
|
if (bh_count) {
|
|
for (i = 0; i < bh_count; i++) {
|
|
bh = bh_arr[i];
|
|
mark_buffer_async_write(bh);
|
|
if (buffer_unwritten(bh))
|
|
set_buffer_unwritten_io(bh);
|
|
set_buffer_uptodate(bh);
|
|
clear_buffer_dirty(bh);
|
|
}
|
|
|
|
for (i = 0; i < bh_count; i++)
|
|
submit_bh(WRITE, bh_arr[i]);
|
|
|
|
if (probed_page && clear_dirty)
|
|
wbc->nr_to_write--; /* Wrote an "extra" page */
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Allocate & map buffers for page given the extent map. Write it out.
|
|
* except for the original page of a writepage, this is called on
|
|
* delalloc/unwritten pages only, for the original page it is possible
|
|
* that the page has no mapping at all.
|
|
*/
|
|
STATIC void
|
|
xfs_convert_page(
|
|
struct inode *inode,
|
|
struct page *page,
|
|
xfs_iomap_t *iomapp,
|
|
struct writeback_control *wbc,
|
|
void *private,
|
|
int startio,
|
|
int all_bh)
|
|
{
|
|
struct buffer_head *bh_arr[MAX_BUF_PER_PAGE], *bh, *head;
|
|
xfs_iomap_t *mp = iomapp, *tmp;
|
|
unsigned long offset, end_offset;
|
|
int index = 0;
|
|
int bbits = inode->i_blkbits;
|
|
int len, page_dirty;
|
|
|
|
end_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1));
|
|
|
|
/*
|
|
* page_dirty is initially a count of buffers on the page before
|
|
* EOF and is decrememted as we move each into a cleanable state.
|
|
*/
|
|
len = 1 << inode->i_blkbits;
|
|
end_offset = max(end_offset, PAGE_CACHE_SIZE);
|
|
end_offset = roundup(end_offset, len);
|
|
page_dirty = end_offset / len;
|
|
|
|
offset = 0;
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (offset >= end_offset)
|
|
break;
|
|
if (!(PageUptodate(page) || buffer_uptodate(bh)))
|
|
continue;
|
|
if (buffer_mapped(bh) && all_bh &&
|
|
!(buffer_unwritten(bh) || buffer_delay(bh))) {
|
|
if (startio) {
|
|
lock_buffer(bh);
|
|
bh_arr[index++] = bh;
|
|
page_dirty--;
|
|
}
|
|
continue;
|
|
}
|
|
tmp = xfs_offset_to_map(page, mp, offset);
|
|
if (!tmp)
|
|
continue;
|
|
ASSERT(!(tmp->iomap_flags & IOMAP_HOLE));
|
|
ASSERT(!(tmp->iomap_flags & IOMAP_DELAY));
|
|
|
|
/* If this is a new unwritten extent buffer (i.e. one
|
|
* that we haven't passed in private data for, we must
|
|
* now map this buffer too.
|
|
*/
|
|
if (buffer_unwritten(bh) && !bh->b_end_io) {
|
|
ASSERT(tmp->iomap_flags & IOMAP_UNWRITTEN);
|
|
xfs_map_unwritten(inode, page, head, bh, offset,
|
|
bbits, tmp, wbc, startio, all_bh);
|
|
} else if (! (buffer_unwritten(bh) && buffer_locked(bh))) {
|
|
xfs_map_at_offset(page, bh, offset, bbits, tmp);
|
|
if (buffer_unwritten(bh)) {
|
|
set_buffer_unwritten_io(bh);
|
|
bh->b_private = private;
|
|
ASSERT(private);
|
|
}
|
|
}
|
|
if (startio) {
|
|
bh_arr[index++] = bh;
|
|
} else {
|
|
set_buffer_dirty(bh);
|
|
unlock_buffer(bh);
|
|
mark_buffer_dirty(bh);
|
|
}
|
|
page_dirty--;
|
|
} while (offset += len, (bh = bh->b_this_page) != head);
|
|
|
|
if (startio && index) {
|
|
xfs_submit_page(page, wbc, bh_arr, index, 1, !page_dirty);
|
|
} else {
|
|
unlock_page(page);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Convert & write out a cluster of pages in the same extent as defined
|
|
* by mp and following the start page.
|
|
*/
|
|
STATIC void
|
|
xfs_cluster_write(
|
|
struct inode *inode,
|
|
pgoff_t tindex,
|
|
xfs_iomap_t *iomapp,
|
|
struct writeback_control *wbc,
|
|
int startio,
|
|
int all_bh,
|
|
pgoff_t tlast)
|
|
{
|
|
struct page *page;
|
|
|
|
for (; tindex <= tlast; tindex++) {
|
|
page = xfs_probe_delalloc_page(inode, tindex);
|
|
if (!page)
|
|
break;
|
|
xfs_convert_page(inode, page, iomapp, wbc, NULL,
|
|
startio, all_bh);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Calling this without startio set means we are being asked to make a dirty
|
|
* page ready for freeing it's buffers. When called with startio set then
|
|
* we are coming from writepage.
|
|
*
|
|
* When called with startio set it is important that we write the WHOLE
|
|
* page if possible.
|
|
* The bh->b_state's cannot know if any of the blocks or which block for
|
|
* that matter are dirty due to mmap writes, and therefore bh uptodate is
|
|
* only vaild if the page itself isn't completely uptodate. Some layers
|
|
* may clear the page dirty flag prior to calling write page, under the
|
|
* assumption the entire page will be written out; by not writing out the
|
|
* whole page the page can be reused before all valid dirty data is
|
|
* written out. Note: in the case of a page that has been dirty'd by
|
|
* mapwrite and but partially setup by block_prepare_write the
|
|
* bh->b_states's will not agree and only ones setup by BPW/BCW will have
|
|
* valid state, thus the whole page must be written out thing.
|
|
*/
|
|
|
|
STATIC int
|
|
xfs_page_state_convert(
|
|
struct inode *inode,
|
|
struct page *page,
|
|
struct writeback_control *wbc,
|
|
int startio,
|
|
int unmapped) /* also implies page uptodate */
|
|
{
|
|
struct buffer_head *bh_arr[MAX_BUF_PER_PAGE], *bh, *head;
|
|
xfs_iomap_t *iomp, iomap;
|
|
loff_t offset;
|
|
unsigned long p_offset = 0;
|
|
__uint64_t end_offset;
|
|
pgoff_t end_index, last_index, tlast;
|
|
int len, err, i, cnt = 0, uptodate = 1;
|
|
int flags;
|
|
int page_dirty;
|
|
|
|
/* wait for other IO threads? */
|
|
flags = (startio && wbc->sync_mode != WB_SYNC_NONE) ? 0 : BMAPI_TRYLOCK;
|
|
|
|
/* Is this page beyond the end of the file? */
|
|
offset = i_size_read(inode);
|
|
end_index = offset >> PAGE_CACHE_SHIFT;
|
|
last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
|
|
if (page->index >= end_index) {
|
|
if ((page->index >= end_index + 1) ||
|
|
!(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
|
|
err = -EIO;
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
end_offset = min_t(unsigned long long,
|
|
(loff_t)(page->index + 1) << PAGE_CACHE_SHIFT, offset);
|
|
offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
|
|
|
|
/*
|
|
* page_dirty is initially a count of buffers on the page before
|
|
* EOF and is decrememted as we move each into a cleanable state.
|
|
*/
|
|
len = 1 << inode->i_blkbits;
|
|
p_offset = max(p_offset, PAGE_CACHE_SIZE);
|
|
p_offset = roundup(p_offset, len);
|
|
page_dirty = p_offset / len;
|
|
|
|
iomp = NULL;
|
|
p_offset = 0;
|
|
bh = head = page_buffers(page);
|
|
|
|
do {
|
|
if (offset >= end_offset)
|
|
break;
|
|
if (!buffer_uptodate(bh))
|
|
uptodate = 0;
|
|
if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio)
|
|
continue;
|
|
|
|
if (iomp) {
|
|
iomp = xfs_offset_to_map(page, &iomap, p_offset);
|
|
}
|
|
|
|
/*
|
|
* First case, map an unwritten extent and prepare for
|
|
* extent state conversion transaction on completion.
|
|
*/
|
|
if (buffer_unwritten(bh)) {
|
|
if (!startio)
|
|
continue;
|
|
if (!iomp) {
|
|
err = xfs_map_blocks(inode, offset, len, &iomap,
|
|
BMAPI_WRITE|BMAPI_IGNSTATE);
|
|
if (err) {
|
|
goto error;
|
|
}
|
|
iomp = xfs_offset_to_map(page, &iomap,
|
|
p_offset);
|
|
}
|
|
if (iomp) {
|
|
if (!bh->b_end_io) {
|
|
err = xfs_map_unwritten(inode, page,
|
|
head, bh, p_offset,
|
|
inode->i_blkbits, iomp,
|
|
wbc, startio, unmapped);
|
|
if (err) {
|
|
goto error;
|
|
}
|
|
} else {
|
|
set_bit(BH_Lock, &bh->b_state);
|
|
}
|
|
BUG_ON(!buffer_locked(bh));
|
|
bh_arr[cnt++] = bh;
|
|
page_dirty--;
|
|
}
|
|
/*
|
|
* Second case, allocate space for a delalloc buffer.
|
|
* We can return EAGAIN here in the release page case.
|
|
*/
|
|
} else if (buffer_delay(bh)) {
|
|
if (!iomp) {
|
|
err = xfs_map_blocks(inode, offset, len, &iomap,
|
|
BMAPI_ALLOCATE | flags);
|
|
if (err) {
|
|
goto error;
|
|
}
|
|
iomp = xfs_offset_to_map(page, &iomap,
|
|
p_offset);
|
|
}
|
|
if (iomp) {
|
|
xfs_map_at_offset(page, bh, p_offset,
|
|
inode->i_blkbits, iomp);
|
|
if (startio) {
|
|
bh_arr[cnt++] = bh;
|
|
} else {
|
|
set_buffer_dirty(bh);
|
|
unlock_buffer(bh);
|
|
mark_buffer_dirty(bh);
|
|
}
|
|
page_dirty--;
|
|
}
|
|
} else if ((buffer_uptodate(bh) || PageUptodate(page)) &&
|
|
(unmapped || startio)) {
|
|
|
|
if (!buffer_mapped(bh)) {
|
|
int size;
|
|
|
|
/*
|
|
* Getting here implies an unmapped buffer
|
|
* was found, and we are in a path where we
|
|
* need to write the whole page out.
|
|
*/
|
|
if (!iomp) {
|
|
size = xfs_probe_unmapped_cluster(
|
|
inode, page, bh, head);
|
|
err = xfs_map_blocks(inode, offset,
|
|
size, &iomap,
|
|
BMAPI_WRITE|BMAPI_MMAP);
|
|
if (err) {
|
|
goto error;
|
|
}
|
|
iomp = xfs_offset_to_map(page, &iomap,
|
|
p_offset);
|
|
}
|
|
if (iomp) {
|
|
xfs_map_at_offset(page,
|
|
bh, p_offset,
|
|
inode->i_blkbits, iomp);
|
|
if (startio) {
|
|
bh_arr[cnt++] = bh;
|
|
} else {
|
|
set_buffer_dirty(bh);
|
|
unlock_buffer(bh);
|
|
mark_buffer_dirty(bh);
|
|
}
|
|
page_dirty--;
|
|
}
|
|
} else if (startio) {
|
|
if (buffer_uptodate(bh) &&
|
|
!test_and_set_bit(BH_Lock, &bh->b_state)) {
|
|
bh_arr[cnt++] = bh;
|
|
page_dirty--;
|
|
}
|
|
}
|
|
}
|
|
} while (offset += len, p_offset += len,
|
|
((bh = bh->b_this_page) != head));
|
|
|
|
if (uptodate && bh == head)
|
|
SetPageUptodate(page);
|
|
|
|
if (startio) {
|
|
xfs_submit_page(page, wbc, bh_arr, cnt, 0, !page_dirty);
|
|
}
|
|
|
|
if (iomp) {
|
|
offset = (iomp->iomap_offset + iomp->iomap_bsize - 1) >>
|
|
PAGE_CACHE_SHIFT;
|
|
tlast = min_t(pgoff_t, offset, last_index);
|
|
xfs_cluster_write(inode, page->index + 1, iomp, wbc,
|
|
startio, unmapped, tlast);
|
|
}
|
|
|
|
return page_dirty;
|
|
|
|
error:
|
|
for (i = 0; i < cnt; i++) {
|
|
unlock_buffer(bh_arr[i]);
|
|
}
|
|
|
|
/*
|
|
* If it's delalloc and we have nowhere to put it,
|
|
* throw it away, unless the lower layers told
|
|
* us to try again.
|
|
*/
|
|
if (err != -EAGAIN) {
|
|
if (!unmapped) {
|
|
block_invalidatepage(page, 0);
|
|
}
|
|
ClearPageUptodate(page);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
STATIC int
|
|
__linvfs_get_block(
|
|
struct inode *inode,
|
|
sector_t iblock,
|
|
unsigned long blocks,
|
|
struct buffer_head *bh_result,
|
|
int create,
|
|
int direct,
|
|
bmapi_flags_t flags)
|
|
{
|
|
vnode_t *vp = LINVFS_GET_VP(inode);
|
|
xfs_iomap_t iomap;
|
|
int retpbbm = 1;
|
|
int error;
|
|
ssize_t size;
|
|
loff_t offset = (loff_t)iblock << inode->i_blkbits;
|
|
|
|
if (blocks)
|
|
size = blocks << inode->i_blkbits;
|
|
else
|
|
size = 1 << inode->i_blkbits;
|
|
|
|
VOP_BMAP(vp, offset, size,
|
|
create ? flags : BMAPI_READ, &iomap, &retpbbm, error);
|
|
if (error)
|
|
return -error;
|
|
|
|
if (retpbbm == 0)
|
|
return 0;
|
|
|
|
if (iomap.iomap_bn != IOMAP_DADDR_NULL) {
|
|
xfs_daddr_t bn;
|
|
loff_t delta;
|
|
|
|
/* For unwritten extents do not report a disk address on
|
|
* the read case (treat as if we're reading into a hole).
|
|
*/
|
|
if (create || !(iomap.iomap_flags & IOMAP_UNWRITTEN)) {
|
|
delta = offset - iomap.iomap_offset;
|
|
delta >>= inode->i_blkbits;
|
|
|
|
bn = iomap.iomap_bn >> (inode->i_blkbits - BBSHIFT);
|
|
bn += delta;
|
|
BUG_ON(!bn && !(iomap.iomap_flags & IOMAP_REALTIME));
|
|
bh_result->b_blocknr = bn;
|
|
set_buffer_mapped(bh_result);
|
|
}
|
|
if (create && (iomap.iomap_flags & IOMAP_UNWRITTEN)) {
|
|
if (direct)
|
|
bh_result->b_private = inode;
|
|
set_buffer_unwritten(bh_result);
|
|
set_buffer_delay(bh_result);
|
|
}
|
|
}
|
|
|
|
/* If this is a realtime file, data might be on a new device */
|
|
bh_result->b_bdev = iomap.iomap_target->pbr_bdev;
|
|
|
|
/* If we previously allocated a block out beyond eof and
|
|
* we are now coming back to use it then we will need to
|
|
* flag it as new even if it has a disk address.
|
|
*/
|
|
if (create &&
|
|
((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
|
|
(offset >= i_size_read(inode)) || (iomap.iomap_flags & IOMAP_NEW))) {
|
|
set_buffer_new(bh_result);
|
|
}
|
|
|
|
if (iomap.iomap_flags & IOMAP_DELAY) {
|
|
BUG_ON(direct);
|
|
if (create) {
|
|
set_buffer_uptodate(bh_result);
|
|
set_buffer_mapped(bh_result);
|
|
set_buffer_delay(bh_result);
|
|
}
|
|
}
|
|
|
|
if (blocks) {
|
|
bh_result->b_size = (ssize_t)min(
|
|
(loff_t)(iomap.iomap_bsize - iomap.iomap_delta),
|
|
(loff_t)(blocks << inode->i_blkbits));
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
linvfs_get_block(
|
|
struct inode *inode,
|
|
sector_t iblock,
|
|
struct buffer_head *bh_result,
|
|
int create)
|
|
{
|
|
return __linvfs_get_block(inode, iblock, 0, bh_result,
|
|
create, 0, BMAPI_WRITE);
|
|
}
|
|
|
|
STATIC int
|
|
linvfs_get_blocks_direct(
|
|
struct inode *inode,
|
|
sector_t iblock,
|
|
unsigned long max_blocks,
|
|
struct buffer_head *bh_result,
|
|
int create)
|
|
{
|
|
return __linvfs_get_block(inode, iblock, max_blocks, bh_result,
|
|
create, 1, BMAPI_WRITE|BMAPI_DIRECT);
|
|
}
|
|
|
|
STATIC void
|
|
linvfs_end_io_direct(
|
|
struct kiocb *iocb,
|
|
loff_t offset,
|
|
ssize_t size,
|
|
void *private)
|
|
{
|
|
xfs_ioend_t *ioend = iocb->private;
|
|
|
|
/*
|
|
* Non-NULL private data means we need to issue a transaction to
|
|
* convert a range from unwritten to written extents. This needs
|
|
* to happen from process contect but aio+dio I/O completion
|
|
* happens from irq context so we need to defer it to a workqueue.
|
|
* This is not nessecary for synchronous direct I/O, but we do
|
|
* it anyway to keep the code uniform and simpler.
|
|
*
|
|
* The core direct I/O code might be changed to always call the
|
|
* completion handler in the future, in which case all this can
|
|
* go away.
|
|
*/
|
|
if (private && size > 0) {
|
|
ioend->io_offset = offset;
|
|
ioend->io_size = size;
|
|
xfs_finish_ioend(ioend);
|
|
} else {
|
|
ASSERT(size >= 0);
|
|
xfs_destroy_ioend(ioend);
|
|
}
|
|
|
|
/*
|
|
* blockdev_direct_IO can return an error even afer the I/O
|
|
* completion handler was called. Thus we need to protect
|
|
* against double-freeing.
|
|
*/
|
|
iocb->private = NULL;
|
|
}
|
|
|
|
STATIC ssize_t
|
|
linvfs_direct_IO(
|
|
int rw,
|
|
struct kiocb *iocb,
|
|
const struct iovec *iov,
|
|
loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
vnode_t *vp = LINVFS_GET_VP(inode);
|
|
xfs_iomap_t iomap;
|
|
int maps = 1;
|
|
int error;
|
|
ssize_t ret;
|
|
|
|
VOP_BMAP(vp, offset, 0, BMAPI_DEVICE, &iomap, &maps, error);
|
|
if (error)
|
|
return -error;
|
|
|
|
iocb->private = xfs_alloc_ioend(inode);
|
|
|
|
ret = blockdev_direct_IO_own_locking(rw, iocb, inode,
|
|
iomap.iomap_target->pbr_bdev,
|
|
iov, offset, nr_segs,
|
|
linvfs_get_blocks_direct,
|
|
linvfs_end_io_direct);
|
|
|
|
if (unlikely(ret <= 0 && iocb->private))
|
|
xfs_destroy_ioend(iocb->private);
|
|
return ret;
|
|
}
|
|
|
|
|
|
STATIC sector_t
|
|
linvfs_bmap(
|
|
struct address_space *mapping,
|
|
sector_t block)
|
|
{
|
|
struct inode *inode = (struct inode *)mapping->host;
|
|
vnode_t *vp = LINVFS_GET_VP(inode);
|
|
int error;
|
|
|
|
vn_trace_entry(vp, "linvfs_bmap", (inst_t *)__return_address);
|
|
|
|
VOP_RWLOCK(vp, VRWLOCK_READ);
|
|
VOP_FLUSH_PAGES(vp, (xfs_off_t)0, -1, 0, FI_REMAPF, error);
|
|
VOP_RWUNLOCK(vp, VRWLOCK_READ);
|
|
return generic_block_bmap(mapping, block, linvfs_get_block);
|
|
}
|
|
|
|
STATIC int
|
|
linvfs_readpage(
|
|
struct file *unused,
|
|
struct page *page)
|
|
{
|
|
return mpage_readpage(page, linvfs_get_block);
|
|
}
|
|
|
|
STATIC int
|
|
linvfs_readpages(
|
|
struct file *unused,
|
|
struct address_space *mapping,
|
|
struct list_head *pages,
|
|
unsigned nr_pages)
|
|
{
|
|
return mpage_readpages(mapping, pages, nr_pages, linvfs_get_block);
|
|
}
|
|
|
|
STATIC void
|
|
xfs_count_page_state(
|
|
struct page *page,
|
|
int *delalloc,
|
|
int *unmapped,
|
|
int *unwritten)
|
|
{
|
|
struct buffer_head *bh, *head;
|
|
|
|
*delalloc = *unmapped = *unwritten = 0;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (buffer_uptodate(bh) && !buffer_mapped(bh))
|
|
(*unmapped) = 1;
|
|
else if (buffer_unwritten(bh) && !buffer_delay(bh))
|
|
clear_buffer_unwritten(bh);
|
|
else if (buffer_unwritten(bh))
|
|
(*unwritten) = 1;
|
|
else if (buffer_delay(bh))
|
|
(*delalloc) = 1;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
}
|
|
|
|
|
|
/*
|
|
* writepage: Called from one of two places:
|
|
*
|
|
* 1. we are flushing a delalloc buffer head.
|
|
*
|
|
* 2. we are writing out a dirty page. Typically the page dirty
|
|
* state is cleared before we get here. In this case is it
|
|
* conceivable we have no buffer heads.
|
|
*
|
|
* For delalloc space on the page we need to allocate space and
|
|
* flush it. For unmapped buffer heads on the page we should
|
|
* allocate space if the page is uptodate. For any other dirty
|
|
* buffer heads on the page we should flush them.
|
|
*
|
|
* If we detect that a transaction would be required to flush
|
|
* the page, we have to check the process flags first, if we
|
|
* are already in a transaction or disk I/O during allocations
|
|
* is off, we need to fail the writepage and redirty the page.
|
|
*/
|
|
|
|
STATIC int
|
|
linvfs_writepage(
|
|
struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
int error;
|
|
int need_trans;
|
|
int delalloc, unmapped, unwritten;
|
|
struct inode *inode = page->mapping->host;
|
|
|
|
xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0);
|
|
|
|
/*
|
|
* We need a transaction if:
|
|
* 1. There are delalloc buffers on the page
|
|
* 2. The page is uptodate and we have unmapped buffers
|
|
* 3. The page is uptodate and we have no buffers
|
|
* 4. There are unwritten buffers on the page
|
|
*/
|
|
|
|
if (!page_has_buffers(page)) {
|
|
unmapped = 1;
|
|
need_trans = 1;
|
|
} else {
|
|
xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
|
|
if (!PageUptodate(page))
|
|
unmapped = 0;
|
|
need_trans = delalloc + unmapped + unwritten;
|
|
}
|
|
|
|
/*
|
|
* If we need a transaction and the process flags say
|
|
* we are already in a transaction, or no IO is allowed
|
|
* then mark the page dirty again and leave the page
|
|
* as is.
|
|
*/
|
|
if (PFLAGS_TEST_FSTRANS() && need_trans)
|
|
goto out_fail;
|
|
|
|
/*
|
|
* Delay hooking up buffer heads until we have
|
|
* made our go/no-go decision.
|
|
*/
|
|
if (!page_has_buffers(page))
|
|
create_empty_buffers(page, 1 << inode->i_blkbits, 0);
|
|
|
|
/*
|
|
* Convert delayed allocate, unwritten or unmapped space
|
|
* to real space and flush out to disk.
|
|
*/
|
|
error = xfs_page_state_convert(inode, page, wbc, 1, unmapped);
|
|
if (error == -EAGAIN)
|
|
goto out_fail;
|
|
if (unlikely(error < 0))
|
|
goto out_unlock;
|
|
|
|
return 0;
|
|
|
|
out_fail:
|
|
redirty_page_for_writepage(wbc, page);
|
|
unlock_page(page);
|
|
return 0;
|
|
out_unlock:
|
|
unlock_page(page);
|
|
return error;
|
|
}
|
|
|
|
STATIC int
|
|
linvfs_invalidate_page(
|
|
struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
xfs_page_trace(XFS_INVALIDPAGE_ENTER,
|
|
page->mapping->host, page, offset);
|
|
return block_invalidatepage(page, offset);
|
|
}
|
|
|
|
/*
|
|
* Called to move a page into cleanable state - and from there
|
|
* to be released. Possibly the page is already clean. We always
|
|
* have buffer heads in this call.
|
|
*
|
|
* Returns 0 if the page is ok to release, 1 otherwise.
|
|
*
|
|
* Possible scenarios are:
|
|
*
|
|
* 1. We are being called to release a page which has been written
|
|
* to via regular I/O. buffer heads will be dirty and possibly
|
|
* delalloc. If no delalloc buffer heads in this case then we
|
|
* can just return zero.
|
|
*
|
|
* 2. We are called to release a page which has been written via
|
|
* mmap, all we need to do is ensure there is no delalloc
|
|
* state in the buffer heads, if not we can let the caller
|
|
* free them and we should come back later via writepage.
|
|
*/
|
|
STATIC int
|
|
linvfs_release_page(
|
|
struct page *page,
|
|
gfp_t gfp_mask)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
int dirty, delalloc, unmapped, unwritten;
|
|
struct writeback_control wbc = {
|
|
.sync_mode = WB_SYNC_ALL,
|
|
.nr_to_write = 1,
|
|
};
|
|
|
|
xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, gfp_mask);
|
|
|
|
xfs_count_page_state(page, &delalloc, &unmapped, &unwritten);
|
|
if (!delalloc && !unwritten)
|
|
goto free_buffers;
|
|
|
|
if (!(gfp_mask & __GFP_FS))
|
|
return 0;
|
|
|
|
/* If we are already inside a transaction or the thread cannot
|
|
* do I/O, we cannot release this page.
|
|
*/
|
|
if (PFLAGS_TEST_FSTRANS())
|
|
return 0;
|
|
|
|
/*
|
|
* Convert delalloc space to real space, do not flush the
|
|
* data out to disk, that will be done by the caller.
|
|
* Never need to allocate space here - we will always
|
|
* come back to writepage in that case.
|
|
*/
|
|
dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0);
|
|
if (dirty == 0 && !unwritten)
|
|
goto free_buffers;
|
|
return 0;
|
|
|
|
free_buffers:
|
|
return try_to_free_buffers(page);
|
|
}
|
|
|
|
STATIC int
|
|
linvfs_prepare_write(
|
|
struct file *file,
|
|
struct page *page,
|
|
unsigned int from,
|
|
unsigned int to)
|
|
{
|
|
return block_prepare_write(page, from, to, linvfs_get_block);
|
|
}
|
|
|
|
struct address_space_operations linvfs_aops = {
|
|
.readpage = linvfs_readpage,
|
|
.readpages = linvfs_readpages,
|
|
.writepage = linvfs_writepage,
|
|
.sync_page = block_sync_page,
|
|
.releasepage = linvfs_release_page,
|
|
.invalidatepage = linvfs_invalidate_page,
|
|
.prepare_write = linvfs_prepare_write,
|
|
.commit_write = generic_commit_write,
|
|
.bmap = linvfs_bmap,
|
|
.direct_IO = linvfs_direct_IO,
|
|
};
|