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![Jan Kara](/assets/img/avatar_default.png)
Currently several places in xfs_find_get_desired_pgoff() handle the case of a missing page. Make them all handled in one place after the loop has terminated. Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
1516 lines
39 KiB
C
1516 lines
39 KiB
C
/*
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* Copyright (c) 2000-2005 Silicon Graphics, Inc.
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms 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,
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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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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "xfs.h"
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#include "xfs_fs.h"
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#include "xfs_shared.h"
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#include "xfs_format.h"
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#include "xfs_log_format.h"
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#include "xfs_trans_resv.h"
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#include "xfs_mount.h"
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#include "xfs_da_format.h"
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#include "xfs_da_btree.h"
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#include "xfs_inode.h"
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#include "xfs_trans.h"
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#include "xfs_inode_item.h"
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#include "xfs_bmap.h"
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#include "xfs_bmap_util.h"
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#include "xfs_error.h"
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#include "xfs_dir2.h"
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#include "xfs_dir2_priv.h"
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#include "xfs_ioctl.h"
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#include "xfs_trace.h"
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#include "xfs_log.h"
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#include "xfs_icache.h"
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#include "xfs_pnfs.h"
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#include "xfs_iomap.h"
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#include "xfs_reflink.h"
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#include <linux/dcache.h>
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#include <linux/falloc.h>
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#include <linux/pagevec.h>
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#include <linux/backing-dev.h>
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static const struct vm_operations_struct xfs_file_vm_ops;
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/*
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* Clear the specified ranges to zero through either the pagecache or DAX.
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* Holes and unwritten extents will be left as-is as they already are zeroed.
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*/
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int
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xfs_zero_range(
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struct xfs_inode *ip,
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xfs_off_t pos,
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xfs_off_t count,
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bool *did_zero)
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{
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return iomap_zero_range(VFS_I(ip), pos, count, NULL, &xfs_iomap_ops);
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}
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int
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xfs_update_prealloc_flags(
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struct xfs_inode *ip,
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enum xfs_prealloc_flags flags)
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{
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struct xfs_trans *tp;
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int error;
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error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_writeid,
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0, 0, 0, &tp);
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if (error)
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return error;
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xfs_ilock(ip, XFS_ILOCK_EXCL);
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xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
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if (!(flags & XFS_PREALLOC_INVISIBLE)) {
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VFS_I(ip)->i_mode &= ~S_ISUID;
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if (VFS_I(ip)->i_mode & S_IXGRP)
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VFS_I(ip)->i_mode &= ~S_ISGID;
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xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
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}
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if (flags & XFS_PREALLOC_SET)
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ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
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if (flags & XFS_PREALLOC_CLEAR)
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ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
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xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
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if (flags & XFS_PREALLOC_SYNC)
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xfs_trans_set_sync(tp);
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return xfs_trans_commit(tp);
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}
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/*
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* Fsync operations on directories are much simpler than on regular files,
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* as there is no file data to flush, and thus also no need for explicit
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* cache flush operations, and there are no non-transaction metadata updates
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* on directories either.
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*/
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STATIC int
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xfs_dir_fsync(
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struct file *file,
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loff_t start,
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loff_t end,
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int datasync)
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{
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struct xfs_inode *ip = XFS_I(file->f_mapping->host);
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struct xfs_mount *mp = ip->i_mount;
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xfs_lsn_t lsn = 0;
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trace_xfs_dir_fsync(ip);
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xfs_ilock(ip, XFS_ILOCK_SHARED);
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if (xfs_ipincount(ip))
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lsn = ip->i_itemp->ili_last_lsn;
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xfs_iunlock(ip, XFS_ILOCK_SHARED);
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if (!lsn)
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return 0;
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return _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, NULL);
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}
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STATIC int
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xfs_file_fsync(
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struct file *file,
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loff_t start,
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loff_t end,
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int datasync)
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{
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struct inode *inode = file->f_mapping->host;
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struct xfs_inode *ip = XFS_I(inode);
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struct xfs_mount *mp = ip->i_mount;
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int error = 0;
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int log_flushed = 0;
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xfs_lsn_t lsn = 0;
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trace_xfs_file_fsync(ip);
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error = filemap_write_and_wait_range(inode->i_mapping, start, end);
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if (error)
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return error;
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if (XFS_FORCED_SHUTDOWN(mp))
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return -EIO;
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xfs_iflags_clear(ip, XFS_ITRUNCATED);
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/*
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* If we have an RT and/or log subvolume we need to make sure to flush
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* the write cache the device used for file data first. This is to
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* ensure newly written file data make it to disk before logging the new
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* inode size in case of an extending write.
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*/
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if (XFS_IS_REALTIME_INODE(ip))
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xfs_blkdev_issue_flush(mp->m_rtdev_targp);
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else if (mp->m_logdev_targp != mp->m_ddev_targp)
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xfs_blkdev_issue_flush(mp->m_ddev_targp);
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/*
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* All metadata updates are logged, which means that we just have to
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* flush the log up to the latest LSN that touched the inode. If we have
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* concurrent fsync/fdatasync() calls, we need them to all block on the
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* log force before we clear the ili_fsync_fields field. This ensures
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* that we don't get a racing sync operation that does not wait for the
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* metadata to hit the journal before returning. If we race with
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* clearing the ili_fsync_fields, then all that will happen is the log
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* force will do nothing as the lsn will already be on disk. We can't
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* race with setting ili_fsync_fields because that is done under
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* XFS_ILOCK_EXCL, and that can't happen because we hold the lock shared
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* until after the ili_fsync_fields is cleared.
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*/
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xfs_ilock(ip, XFS_ILOCK_SHARED);
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if (xfs_ipincount(ip)) {
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if (!datasync ||
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(ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP))
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lsn = ip->i_itemp->ili_last_lsn;
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}
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if (lsn) {
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error = _xfs_log_force_lsn(mp, lsn, XFS_LOG_SYNC, &log_flushed);
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ip->i_itemp->ili_fsync_fields = 0;
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}
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xfs_iunlock(ip, XFS_ILOCK_SHARED);
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/*
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* If we only have a single device, and the log force about was
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* a no-op we might have to flush the data device cache here.
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* This can only happen for fdatasync/O_DSYNC if we were overwriting
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* an already allocated file and thus do not have any metadata to
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* commit.
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*/
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if (!log_flushed && !XFS_IS_REALTIME_INODE(ip) &&
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mp->m_logdev_targp == mp->m_ddev_targp)
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xfs_blkdev_issue_flush(mp->m_ddev_targp);
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return error;
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}
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STATIC ssize_t
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xfs_file_dio_aio_read(
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struct kiocb *iocb,
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struct iov_iter *to)
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{
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struct xfs_inode *ip = XFS_I(file_inode(iocb->ki_filp));
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size_t count = iov_iter_count(to);
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ssize_t ret;
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trace_xfs_file_direct_read(ip, count, iocb->ki_pos);
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if (!count)
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return 0; /* skip atime */
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file_accessed(iocb->ki_filp);
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xfs_ilock(ip, XFS_IOLOCK_SHARED);
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ret = iomap_dio_rw(iocb, to, &xfs_iomap_ops, NULL);
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xfs_iunlock(ip, XFS_IOLOCK_SHARED);
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return ret;
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}
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static noinline ssize_t
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xfs_file_dax_read(
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struct kiocb *iocb,
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struct iov_iter *to)
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{
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struct xfs_inode *ip = XFS_I(iocb->ki_filp->f_mapping->host);
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size_t count = iov_iter_count(to);
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ssize_t ret = 0;
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trace_xfs_file_dax_read(ip, count, iocb->ki_pos);
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if (!count)
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return 0; /* skip atime */
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xfs_ilock(ip, XFS_IOLOCK_SHARED);
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ret = dax_iomap_rw(iocb, to, &xfs_iomap_ops);
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xfs_iunlock(ip, XFS_IOLOCK_SHARED);
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file_accessed(iocb->ki_filp);
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return ret;
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}
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STATIC ssize_t
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xfs_file_buffered_aio_read(
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struct kiocb *iocb,
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struct iov_iter *to)
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{
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struct xfs_inode *ip = XFS_I(file_inode(iocb->ki_filp));
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ssize_t ret;
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trace_xfs_file_buffered_read(ip, iov_iter_count(to), iocb->ki_pos);
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xfs_ilock(ip, XFS_IOLOCK_SHARED);
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ret = generic_file_read_iter(iocb, to);
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xfs_iunlock(ip, XFS_IOLOCK_SHARED);
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return ret;
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}
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STATIC ssize_t
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xfs_file_read_iter(
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struct kiocb *iocb,
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struct iov_iter *to)
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{
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struct inode *inode = file_inode(iocb->ki_filp);
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struct xfs_mount *mp = XFS_I(inode)->i_mount;
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ssize_t ret = 0;
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XFS_STATS_INC(mp, xs_read_calls);
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if (XFS_FORCED_SHUTDOWN(mp))
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return -EIO;
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if (IS_DAX(inode))
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ret = xfs_file_dax_read(iocb, to);
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else if (iocb->ki_flags & IOCB_DIRECT)
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ret = xfs_file_dio_aio_read(iocb, to);
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else
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ret = xfs_file_buffered_aio_read(iocb, to);
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if (ret > 0)
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XFS_STATS_ADD(mp, xs_read_bytes, ret);
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return ret;
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}
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/*
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* Zero any on disk space between the current EOF and the new, larger EOF.
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*
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* This handles the normal case of zeroing the remainder of the last block in
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* the file and the unusual case of zeroing blocks out beyond the size of the
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* file. This second case only happens with fixed size extents and when the
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* system crashes before the inode size was updated but after blocks were
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* allocated.
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*
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* Expects the iolock to be held exclusive, and will take the ilock internally.
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*/
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int /* error (positive) */
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xfs_zero_eof(
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struct xfs_inode *ip,
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xfs_off_t offset, /* starting I/O offset */
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xfs_fsize_t isize, /* current inode size */
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bool *did_zeroing)
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{
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ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
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ASSERT(offset > isize);
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trace_xfs_zero_eof(ip, isize, offset - isize);
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return xfs_zero_range(ip, isize, offset - isize, did_zeroing);
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}
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/*
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* Common pre-write limit and setup checks.
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*
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* Called with the iolocked held either shared and exclusive according to
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* @iolock, and returns with it held. Might upgrade the iolock to exclusive
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* if called for a direct write beyond i_size.
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*/
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STATIC ssize_t
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xfs_file_aio_write_checks(
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struct kiocb *iocb,
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struct iov_iter *from,
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int *iolock)
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{
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struct file *file = iocb->ki_filp;
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struct inode *inode = file->f_mapping->host;
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struct xfs_inode *ip = XFS_I(inode);
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ssize_t error = 0;
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size_t count = iov_iter_count(from);
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bool drained_dio = false;
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restart:
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error = generic_write_checks(iocb, from);
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if (error <= 0)
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return error;
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error = xfs_break_layouts(inode, iolock);
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if (error)
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return error;
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/*
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* For changing security info in file_remove_privs() we need i_rwsem
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* exclusively.
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*/
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if (*iolock == XFS_IOLOCK_SHARED && !IS_NOSEC(inode)) {
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xfs_iunlock(ip, *iolock);
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*iolock = XFS_IOLOCK_EXCL;
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xfs_ilock(ip, *iolock);
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goto restart;
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}
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/*
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* If the offset is beyond the size of the file, we need to zero any
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* blocks that fall between the existing EOF and the start of this
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* write. If zeroing is needed and we are currently holding the
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* iolock shared, we need to update it to exclusive which implies
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* having to redo all checks before.
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*
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* We need to serialise against EOF updates that occur in IO
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* completions here. We want to make sure that nobody is changing the
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* size while we do this check until we have placed an IO barrier (i.e.
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* hold the XFS_IOLOCK_EXCL) that prevents new IO from being dispatched.
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* The spinlock effectively forms a memory barrier once we have the
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* XFS_IOLOCK_EXCL so we are guaranteed to see the latest EOF value
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* and hence be able to correctly determine if we need to run zeroing.
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*/
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spin_lock(&ip->i_flags_lock);
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if (iocb->ki_pos > i_size_read(inode)) {
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bool zero = false;
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spin_unlock(&ip->i_flags_lock);
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if (!drained_dio) {
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if (*iolock == XFS_IOLOCK_SHARED) {
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xfs_iunlock(ip, *iolock);
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*iolock = XFS_IOLOCK_EXCL;
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xfs_ilock(ip, *iolock);
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iov_iter_reexpand(from, count);
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}
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/*
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* We now have an IO submission barrier in place, but
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* AIO can do EOF updates during IO completion and hence
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* we now need to wait for all of them to drain. Non-AIO
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* DIO will have drained before we are given the
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* XFS_IOLOCK_EXCL, and so for most cases this wait is a
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* no-op.
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*/
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inode_dio_wait(inode);
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drained_dio = true;
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goto restart;
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}
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error = xfs_zero_eof(ip, iocb->ki_pos, i_size_read(inode), &zero);
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if (error)
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return error;
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} else
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spin_unlock(&ip->i_flags_lock);
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|
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/*
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* Updating the timestamps will grab the ilock again from
|
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* xfs_fs_dirty_inode, so we have to call it after dropping the
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* lock above. Eventually we should look into a way to avoid
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* the pointless lock roundtrip.
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*/
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if (likely(!(file->f_mode & FMODE_NOCMTIME))) {
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error = file_update_time(file);
|
|
if (error)
|
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return error;
|
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}
|
|
|
|
/*
|
|
* If we're writing the file then make sure to clear the setuid and
|
|
* setgid bits if the process is not being run by root. This keeps
|
|
* people from modifying setuid and setgid binaries.
|
|
*/
|
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if (!IS_NOSEC(inode))
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return file_remove_privs(file);
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return 0;
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}
|
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|
|
static int
|
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xfs_dio_write_end_io(
|
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struct kiocb *iocb,
|
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ssize_t size,
|
|
unsigned flags)
|
|
{
|
|
struct inode *inode = file_inode(iocb->ki_filp);
|
|
struct xfs_inode *ip = XFS_I(inode);
|
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loff_t offset = iocb->ki_pos;
|
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bool update_size = false;
|
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int error = 0;
|
|
|
|
trace_xfs_end_io_direct_write(ip, offset, size);
|
|
|
|
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
|
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return -EIO;
|
|
|
|
if (size <= 0)
|
|
return size;
|
|
|
|
/*
|
|
* We need to update the in-core inode size here so that we don't end up
|
|
* with the on-disk inode size being outside the in-core inode size. We
|
|
* have no other method of updating EOF for AIO, so always do it here
|
|
* if necessary.
|
|
*
|
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* We need to lock the test/set EOF update as we can be racing with
|
|
* other IO completions here to update the EOF. Failing to serialise
|
|
* here can result in EOF moving backwards and Bad Things Happen when
|
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* that occurs.
|
|
*/
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spin_lock(&ip->i_flags_lock);
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if (offset + size > i_size_read(inode)) {
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i_size_write(inode, offset + size);
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update_size = true;
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}
|
|
spin_unlock(&ip->i_flags_lock);
|
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|
|
if (flags & IOMAP_DIO_COW) {
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error = xfs_reflink_end_cow(ip, offset, size);
|
|
if (error)
|
|
return error;
|
|
}
|
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|
|
if (flags & IOMAP_DIO_UNWRITTEN)
|
|
error = xfs_iomap_write_unwritten(ip, offset, size);
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else if (update_size)
|
|
error = xfs_setfilesize(ip, offset, size);
|
|
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* xfs_file_dio_aio_write - handle direct IO writes
|
|
*
|
|
* Lock the inode appropriately to prepare for and issue a direct IO write.
|
|
* By separating it from the buffered write path we remove all the tricky to
|
|
* follow locking changes and looping.
|
|
*
|
|
* If there are cached pages or we're extending the file, we need IOLOCK_EXCL
|
|
* until we're sure the bytes at the new EOF have been zeroed and/or the cached
|
|
* pages are flushed out.
|
|
*
|
|
* In most cases the direct IO writes will be done holding IOLOCK_SHARED
|
|
* allowing them to be done in parallel with reads and other direct IO writes.
|
|
* However, if the IO is not aligned to filesystem blocks, the direct IO layer
|
|
* needs to do sub-block zeroing and that requires serialisation against other
|
|
* direct IOs to the same block. In this case we need to serialise the
|
|
* submission of the unaligned IOs so that we don't get racing block zeroing in
|
|
* the dio layer. To avoid the problem with aio, we also need to wait for
|
|
* outstanding IOs to complete so that unwritten extent conversion is completed
|
|
* before we try to map the overlapping block. This is currently implemented by
|
|
* hitting it with a big hammer (i.e. inode_dio_wait()).
|
|
*
|
|
* Returns with locks held indicated by @iolock and errors indicated by
|
|
* negative return values.
|
|
*/
|
|
STATIC ssize_t
|
|
xfs_file_dio_aio_write(
|
|
struct kiocb *iocb,
|
|
struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct address_space *mapping = file->f_mapping;
|
|
struct inode *inode = mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
ssize_t ret = 0;
|
|
int unaligned_io = 0;
|
|
int iolock;
|
|
size_t count = iov_iter_count(from);
|
|
struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
|
|
mp->m_rtdev_targp : mp->m_ddev_targp;
|
|
|
|
/* DIO must be aligned to device logical sector size */
|
|
if ((iocb->ki_pos | count) & target->bt_logical_sectormask)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Don't take the exclusive iolock here unless the I/O is unaligned to
|
|
* the file system block size. We don't need to consider the EOF
|
|
* extension case here because xfs_file_aio_write_checks() will relock
|
|
* the inode as necessary for EOF zeroing cases and fill out the new
|
|
* inode size as appropriate.
|
|
*/
|
|
if ((iocb->ki_pos & mp->m_blockmask) ||
|
|
((iocb->ki_pos + count) & mp->m_blockmask)) {
|
|
unaligned_io = 1;
|
|
|
|
/*
|
|
* We can't properly handle unaligned direct I/O to reflink
|
|
* files yet, as we can't unshare a partial block.
|
|
*/
|
|
if (xfs_is_reflink_inode(ip)) {
|
|
trace_xfs_reflink_bounce_dio_write(ip, iocb->ki_pos, count);
|
|
return -EREMCHG;
|
|
}
|
|
iolock = XFS_IOLOCK_EXCL;
|
|
} else {
|
|
iolock = XFS_IOLOCK_SHARED;
|
|
}
|
|
|
|
xfs_ilock(ip, iolock);
|
|
|
|
ret = xfs_file_aio_write_checks(iocb, from, &iolock);
|
|
if (ret)
|
|
goto out;
|
|
count = iov_iter_count(from);
|
|
|
|
/*
|
|
* If we are doing unaligned IO, wait for all other IO to drain,
|
|
* otherwise demote the lock if we had to take the exclusive lock
|
|
* for other reasons in xfs_file_aio_write_checks.
|
|
*/
|
|
if (unaligned_io)
|
|
inode_dio_wait(inode);
|
|
else if (iolock == XFS_IOLOCK_EXCL) {
|
|
xfs_ilock_demote(ip, XFS_IOLOCK_EXCL);
|
|
iolock = XFS_IOLOCK_SHARED;
|
|
}
|
|
|
|
trace_xfs_file_direct_write(ip, count, iocb->ki_pos);
|
|
ret = iomap_dio_rw(iocb, from, &xfs_iomap_ops, xfs_dio_write_end_io);
|
|
out:
|
|
xfs_iunlock(ip, iolock);
|
|
|
|
/*
|
|
* No fallback to buffered IO on errors for XFS, direct IO will either
|
|
* complete fully or fail.
|
|
*/
|
|
ASSERT(ret < 0 || ret == count);
|
|
return ret;
|
|
}
|
|
|
|
static noinline ssize_t
|
|
xfs_file_dax_write(
|
|
struct kiocb *iocb,
|
|
struct iov_iter *from)
|
|
{
|
|
struct inode *inode = iocb->ki_filp->f_mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
int iolock = XFS_IOLOCK_EXCL;
|
|
ssize_t ret, error = 0;
|
|
size_t count;
|
|
loff_t pos;
|
|
|
|
xfs_ilock(ip, iolock);
|
|
ret = xfs_file_aio_write_checks(iocb, from, &iolock);
|
|
if (ret)
|
|
goto out;
|
|
|
|
pos = iocb->ki_pos;
|
|
count = iov_iter_count(from);
|
|
|
|
trace_xfs_file_dax_write(ip, count, pos);
|
|
ret = dax_iomap_rw(iocb, from, &xfs_iomap_ops);
|
|
if (ret > 0 && iocb->ki_pos > i_size_read(inode)) {
|
|
i_size_write(inode, iocb->ki_pos);
|
|
error = xfs_setfilesize(ip, pos, ret);
|
|
}
|
|
out:
|
|
xfs_iunlock(ip, iolock);
|
|
return error ? error : ret;
|
|
}
|
|
|
|
STATIC ssize_t
|
|
xfs_file_buffered_aio_write(
|
|
struct kiocb *iocb,
|
|
struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct address_space *mapping = file->f_mapping;
|
|
struct inode *inode = mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
ssize_t ret;
|
|
int enospc = 0;
|
|
int iolock;
|
|
|
|
write_retry:
|
|
iolock = XFS_IOLOCK_EXCL;
|
|
xfs_ilock(ip, iolock);
|
|
|
|
ret = xfs_file_aio_write_checks(iocb, from, &iolock);
|
|
if (ret)
|
|
goto out;
|
|
|
|
/* We can write back this queue in page reclaim */
|
|
current->backing_dev_info = inode_to_bdi(inode);
|
|
|
|
trace_xfs_file_buffered_write(ip, iov_iter_count(from), iocb->ki_pos);
|
|
ret = iomap_file_buffered_write(iocb, from, &xfs_iomap_ops);
|
|
if (likely(ret >= 0))
|
|
iocb->ki_pos += ret;
|
|
|
|
/*
|
|
* If we hit a space limit, try to free up some lingering preallocated
|
|
* space before returning an error. In the case of ENOSPC, first try to
|
|
* write back all dirty inodes to free up some of the excess reserved
|
|
* metadata space. This reduces the chances that the eofblocks scan
|
|
* waits on dirty mappings. Since xfs_flush_inodes() is serialized, this
|
|
* also behaves as a filter to prevent too many eofblocks scans from
|
|
* running at the same time.
|
|
*/
|
|
if (ret == -EDQUOT && !enospc) {
|
|
xfs_iunlock(ip, iolock);
|
|
enospc = xfs_inode_free_quota_eofblocks(ip);
|
|
if (enospc)
|
|
goto write_retry;
|
|
enospc = xfs_inode_free_quota_cowblocks(ip);
|
|
if (enospc)
|
|
goto write_retry;
|
|
iolock = 0;
|
|
} else if (ret == -ENOSPC && !enospc) {
|
|
struct xfs_eofblocks eofb = {0};
|
|
|
|
enospc = 1;
|
|
xfs_flush_inodes(ip->i_mount);
|
|
|
|
xfs_iunlock(ip, iolock);
|
|
eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
|
|
xfs_icache_free_eofblocks(ip->i_mount, &eofb);
|
|
goto write_retry;
|
|
}
|
|
|
|
current->backing_dev_info = NULL;
|
|
out:
|
|
if (iolock)
|
|
xfs_iunlock(ip, iolock);
|
|
return ret;
|
|
}
|
|
|
|
STATIC ssize_t
|
|
xfs_file_write_iter(
|
|
struct kiocb *iocb,
|
|
struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct address_space *mapping = file->f_mapping;
|
|
struct inode *inode = mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
ssize_t ret;
|
|
size_t ocount = iov_iter_count(from);
|
|
|
|
XFS_STATS_INC(ip->i_mount, xs_write_calls);
|
|
|
|
if (ocount == 0)
|
|
return 0;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(ip->i_mount))
|
|
return -EIO;
|
|
|
|
if (IS_DAX(inode))
|
|
ret = xfs_file_dax_write(iocb, from);
|
|
else if (iocb->ki_flags & IOCB_DIRECT) {
|
|
/*
|
|
* Allow a directio write to fall back to a buffered
|
|
* write *only* in the case that we're doing a reflink
|
|
* CoW. In all other directio scenarios we do not
|
|
* allow an operation to fall back to buffered mode.
|
|
*/
|
|
ret = xfs_file_dio_aio_write(iocb, from);
|
|
if (ret == -EREMCHG)
|
|
goto buffered;
|
|
} else {
|
|
buffered:
|
|
ret = xfs_file_buffered_aio_write(iocb, from);
|
|
}
|
|
|
|
if (ret > 0) {
|
|
XFS_STATS_ADD(ip->i_mount, xs_write_bytes, ret);
|
|
|
|
/* Handle various SYNC-type writes */
|
|
ret = generic_write_sync(iocb, ret);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
#define XFS_FALLOC_FL_SUPPORTED \
|
|
(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
|
|
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
|
|
FALLOC_FL_INSERT_RANGE | FALLOC_FL_UNSHARE_RANGE)
|
|
|
|
STATIC long
|
|
xfs_file_fallocate(
|
|
struct file *file,
|
|
int mode,
|
|
loff_t offset,
|
|
loff_t len)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
long error;
|
|
enum xfs_prealloc_flags flags = 0;
|
|
uint iolock = XFS_IOLOCK_EXCL;
|
|
loff_t new_size = 0;
|
|
bool do_file_insert = 0;
|
|
|
|
if (!S_ISREG(inode->i_mode))
|
|
return -EINVAL;
|
|
if (mode & ~XFS_FALLOC_FL_SUPPORTED)
|
|
return -EOPNOTSUPP;
|
|
|
|
xfs_ilock(ip, iolock);
|
|
error = xfs_break_layouts(inode, &iolock);
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
|
|
iolock |= XFS_MMAPLOCK_EXCL;
|
|
|
|
if (mode & FALLOC_FL_PUNCH_HOLE) {
|
|
error = xfs_free_file_space(ip, offset, len);
|
|
if (error)
|
|
goto out_unlock;
|
|
} else if (mode & FALLOC_FL_COLLAPSE_RANGE) {
|
|
unsigned int blksize_mask = i_blocksize(inode) - 1;
|
|
|
|
if (offset & blksize_mask || len & blksize_mask) {
|
|
error = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/*
|
|
* There is no need to overlap collapse range with EOF,
|
|
* in which case it is effectively a truncate operation
|
|
*/
|
|
if (offset + len >= i_size_read(inode)) {
|
|
error = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
new_size = i_size_read(inode) - len;
|
|
|
|
error = xfs_collapse_file_space(ip, offset, len);
|
|
if (error)
|
|
goto out_unlock;
|
|
} else if (mode & FALLOC_FL_INSERT_RANGE) {
|
|
unsigned int blksize_mask = i_blocksize(inode) - 1;
|
|
|
|
new_size = i_size_read(inode) + len;
|
|
if (offset & blksize_mask || len & blksize_mask) {
|
|
error = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* check the new inode size does not wrap through zero */
|
|
if (new_size > inode->i_sb->s_maxbytes) {
|
|
error = -EFBIG;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* Offset should be less than i_size */
|
|
if (offset >= i_size_read(inode)) {
|
|
error = -EINVAL;
|
|
goto out_unlock;
|
|
}
|
|
do_file_insert = 1;
|
|
} else {
|
|
flags |= XFS_PREALLOC_SET;
|
|
|
|
if (!(mode & FALLOC_FL_KEEP_SIZE) &&
|
|
offset + len > i_size_read(inode)) {
|
|
new_size = offset + len;
|
|
error = inode_newsize_ok(inode, new_size);
|
|
if (error)
|
|
goto out_unlock;
|
|
}
|
|
|
|
if (mode & FALLOC_FL_ZERO_RANGE)
|
|
error = xfs_zero_file_space(ip, offset, len);
|
|
else {
|
|
if (mode & FALLOC_FL_UNSHARE_RANGE) {
|
|
error = xfs_reflink_unshare(ip, offset, len);
|
|
if (error)
|
|
goto out_unlock;
|
|
}
|
|
error = xfs_alloc_file_space(ip, offset, len,
|
|
XFS_BMAPI_PREALLOC);
|
|
}
|
|
if (error)
|
|
goto out_unlock;
|
|
}
|
|
|
|
if (file->f_flags & O_DSYNC)
|
|
flags |= XFS_PREALLOC_SYNC;
|
|
|
|
error = xfs_update_prealloc_flags(ip, flags);
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
/* Change file size if needed */
|
|
if (new_size) {
|
|
struct iattr iattr;
|
|
|
|
iattr.ia_valid = ATTR_SIZE;
|
|
iattr.ia_size = new_size;
|
|
error = xfs_vn_setattr_size(file_dentry(file), &iattr);
|
|
if (error)
|
|
goto out_unlock;
|
|
}
|
|
|
|
/*
|
|
* Perform hole insertion now that the file size has been
|
|
* updated so that if we crash during the operation we don't
|
|
* leave shifted extents past EOF and hence losing access to
|
|
* the data that is contained within them.
|
|
*/
|
|
if (do_file_insert)
|
|
error = xfs_insert_file_space(ip, offset, len);
|
|
|
|
out_unlock:
|
|
xfs_iunlock(ip, iolock);
|
|
return error;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_file_clone_range(
|
|
struct file *file_in,
|
|
loff_t pos_in,
|
|
struct file *file_out,
|
|
loff_t pos_out,
|
|
u64 len)
|
|
{
|
|
return xfs_reflink_remap_range(file_in, pos_in, file_out, pos_out,
|
|
len, false);
|
|
}
|
|
|
|
STATIC ssize_t
|
|
xfs_file_dedupe_range(
|
|
struct file *src_file,
|
|
u64 loff,
|
|
u64 len,
|
|
struct file *dst_file,
|
|
u64 dst_loff)
|
|
{
|
|
int error;
|
|
|
|
error = xfs_reflink_remap_range(src_file, loff, dst_file, dst_loff,
|
|
len, true);
|
|
if (error)
|
|
return error;
|
|
return len;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_file_open(
|
|
struct inode *inode,
|
|
struct file *file)
|
|
{
|
|
if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
|
|
return -EFBIG;
|
|
if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
|
|
return -EIO;
|
|
return 0;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_dir_open(
|
|
struct inode *inode,
|
|
struct file *file)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
int mode;
|
|
int error;
|
|
|
|
error = xfs_file_open(inode, file);
|
|
if (error)
|
|
return error;
|
|
|
|
/*
|
|
* If there are any blocks, read-ahead block 0 as we're almost
|
|
* certain to have the next operation be a read there.
|
|
*/
|
|
mode = xfs_ilock_data_map_shared(ip);
|
|
if (ip->i_d.di_nextents > 0)
|
|
error = xfs_dir3_data_readahead(ip, 0, -1);
|
|
xfs_iunlock(ip, mode);
|
|
return error;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_file_release(
|
|
struct inode *inode,
|
|
struct file *filp)
|
|
{
|
|
return xfs_release(XFS_I(inode));
|
|
}
|
|
|
|
STATIC int
|
|
xfs_file_readdir(
|
|
struct file *file,
|
|
struct dir_context *ctx)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
xfs_inode_t *ip = XFS_I(inode);
|
|
size_t bufsize;
|
|
|
|
/*
|
|
* The Linux API doesn't pass down the total size of the buffer
|
|
* we read into down to the filesystem. With the filldir concept
|
|
* it's not needed for correct information, but the XFS dir2 leaf
|
|
* code wants an estimate of the buffer size to calculate it's
|
|
* readahead window and size the buffers used for mapping to
|
|
* physical blocks.
|
|
*
|
|
* Try to give it an estimate that's good enough, maybe at some
|
|
* point we can change the ->readdir prototype to include the
|
|
* buffer size. For now we use the current glibc buffer size.
|
|
*/
|
|
bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size);
|
|
|
|
return xfs_readdir(ip, ctx, bufsize);
|
|
}
|
|
|
|
/*
|
|
* This type is designed to indicate the type of offset we would like
|
|
* to search from page cache for xfs_seek_hole_data().
|
|
*/
|
|
enum {
|
|
HOLE_OFF = 0,
|
|
DATA_OFF,
|
|
};
|
|
|
|
/*
|
|
* Lookup the desired type of offset from the given page.
|
|
*
|
|
* On success, return true and the offset argument will point to the
|
|
* start of the region that was found. Otherwise this function will
|
|
* return false and keep the offset argument unchanged.
|
|
*/
|
|
STATIC bool
|
|
xfs_lookup_buffer_offset(
|
|
struct page *page,
|
|
loff_t *offset,
|
|
unsigned int type)
|
|
{
|
|
loff_t lastoff = page_offset(page);
|
|
bool found = false;
|
|
struct buffer_head *bh, *head;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
/*
|
|
* Unwritten extents that have data in the page
|
|
* cache covering them can be identified by the
|
|
* BH_Unwritten state flag. Pages with multiple
|
|
* buffers might have a mix of holes, data and
|
|
* unwritten extents - any buffer with valid
|
|
* data in it should have BH_Uptodate flag set
|
|
* on it.
|
|
*/
|
|
if (buffer_unwritten(bh) ||
|
|
buffer_uptodate(bh)) {
|
|
if (type == DATA_OFF)
|
|
found = true;
|
|
} else {
|
|
if (type == HOLE_OFF)
|
|
found = true;
|
|
}
|
|
|
|
if (found) {
|
|
*offset = lastoff;
|
|
break;
|
|
}
|
|
lastoff += bh->b_size;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
|
|
return found;
|
|
}
|
|
|
|
/*
|
|
* This routine is called to find out and return a data or hole offset
|
|
* from the page cache for unwritten extents according to the desired
|
|
* type for xfs_seek_hole_data().
|
|
*
|
|
* The argument offset is used to tell where we start to search from the
|
|
* page cache. Map is used to figure out the end points of the range to
|
|
* lookup pages.
|
|
*
|
|
* Return true if the desired type of offset was found, and the argument
|
|
* offset is filled with that address. Otherwise, return false and keep
|
|
* offset unchanged.
|
|
*/
|
|
STATIC bool
|
|
xfs_find_get_desired_pgoff(
|
|
struct inode *inode,
|
|
struct xfs_bmbt_irec *map,
|
|
unsigned int type,
|
|
loff_t *offset)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
struct pagevec pvec;
|
|
pgoff_t index;
|
|
pgoff_t end;
|
|
loff_t endoff;
|
|
loff_t startoff = *offset;
|
|
loff_t lastoff = startoff;
|
|
bool found = false;
|
|
|
|
pagevec_init(&pvec, 0);
|
|
|
|
index = startoff >> PAGE_SHIFT;
|
|
endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
|
|
end = (endoff - 1) >> PAGE_SHIFT;
|
|
do {
|
|
int want;
|
|
unsigned nr_pages;
|
|
unsigned int i;
|
|
|
|
want = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1;
|
|
nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
|
|
want);
|
|
if (nr_pages == 0)
|
|
break;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
loff_t b_offset;
|
|
|
|
/*
|
|
* At this point, the page may be truncated or
|
|
* invalidated (changing page->mapping to NULL),
|
|
* or even swizzled back from swapper_space to tmpfs
|
|
* file mapping. However, page->index will not change
|
|
* because we have a reference on the page.
|
|
*
|
|
* If current page offset is beyond where we've ended,
|
|
* we've found a hole.
|
|
*/
|
|
if (type == HOLE_OFF && lastoff < endoff &&
|
|
lastoff < page_offset(pvec.pages[i])) {
|
|
found = true;
|
|
*offset = lastoff;
|
|
goto out;
|
|
}
|
|
/* Searching done if the page index is out of range. */
|
|
if (page->index > end)
|
|
goto out;
|
|
|
|
lock_page(page);
|
|
/*
|
|
* Page truncated or invalidated(page->mapping == NULL).
|
|
* We can freely skip it and proceed to check the next
|
|
* page.
|
|
*/
|
|
if (unlikely(page->mapping != inode->i_mapping)) {
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
if (!page_has_buffers(page)) {
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
found = xfs_lookup_buffer_offset(page, &b_offset, type);
|
|
if (found) {
|
|
/*
|
|
* The found offset may be less than the start
|
|
* point to search if this is the first time to
|
|
* come here.
|
|
*/
|
|
*offset = max_t(loff_t, startoff, b_offset);
|
|
unlock_page(page);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* We either searching data but nothing was found, or
|
|
* searching hole but found a data buffer. In either
|
|
* case, probably the next page contains the desired
|
|
* things, update the last offset to it so.
|
|
*/
|
|
lastoff = page_offset(page) + PAGE_SIZE;
|
|
unlock_page(page);
|
|
}
|
|
|
|
/*
|
|
* The number of returned pages less than our desired, search
|
|
* done.
|
|
*/
|
|
if (nr_pages < want)
|
|
break;
|
|
|
|
index = pvec.pages[i - 1]->index + 1;
|
|
pagevec_release(&pvec);
|
|
} while (index <= end);
|
|
|
|
/* No page at lastoff and we are not done - we found a hole. */
|
|
if (type == HOLE_OFF && lastoff < endoff) {
|
|
*offset = lastoff;
|
|
found = true;
|
|
}
|
|
out:
|
|
pagevec_release(&pvec);
|
|
return found;
|
|
}
|
|
|
|
/*
|
|
* caller must lock inode with xfs_ilock_data_map_shared,
|
|
* can we craft an appropriate ASSERT?
|
|
*
|
|
* end is because the VFS-level lseek interface is defined such that any
|
|
* offset past i_size shall return -ENXIO, but we use this for quota code
|
|
* which does not maintain i_size, and we want to SEEK_DATA past i_size.
|
|
*/
|
|
loff_t
|
|
__xfs_seek_hole_data(
|
|
struct inode *inode,
|
|
loff_t start,
|
|
loff_t end,
|
|
int whence)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
loff_t uninitialized_var(offset);
|
|
xfs_fileoff_t fsbno;
|
|
xfs_filblks_t lastbno;
|
|
int error;
|
|
|
|
if (start >= end) {
|
|
error = -ENXIO;
|
|
goto out_error;
|
|
}
|
|
|
|
/*
|
|
* Try to read extents from the first block indicated
|
|
* by fsbno to the end block of the file.
|
|
*/
|
|
fsbno = XFS_B_TO_FSBT(mp, start);
|
|
lastbno = XFS_B_TO_FSB(mp, end);
|
|
|
|
for (;;) {
|
|
struct xfs_bmbt_irec map[2];
|
|
int nmap = 2;
|
|
unsigned int i;
|
|
|
|
error = xfs_bmapi_read(ip, fsbno, lastbno - fsbno, map, &nmap,
|
|
XFS_BMAPI_ENTIRE);
|
|
if (error)
|
|
goto out_error;
|
|
|
|
/* No extents at given offset, must be beyond EOF */
|
|
if (nmap == 0) {
|
|
error = -ENXIO;
|
|
goto out_error;
|
|
}
|
|
|
|
for (i = 0; i < nmap; i++) {
|
|
offset = max_t(loff_t, start,
|
|
XFS_FSB_TO_B(mp, map[i].br_startoff));
|
|
|
|
/* Landed in the hole we wanted? */
|
|
if (whence == SEEK_HOLE &&
|
|
map[i].br_startblock == HOLESTARTBLOCK)
|
|
goto out;
|
|
|
|
/* Landed in the data extent we wanted? */
|
|
if (whence == SEEK_DATA &&
|
|
(map[i].br_startblock == DELAYSTARTBLOCK ||
|
|
(map[i].br_state == XFS_EXT_NORM &&
|
|
!isnullstartblock(map[i].br_startblock))))
|
|
goto out;
|
|
|
|
/*
|
|
* Landed in an unwritten extent, try to search
|
|
* for hole or data from page cache.
|
|
*/
|
|
if (map[i].br_state == XFS_EXT_UNWRITTEN) {
|
|
if (xfs_find_get_desired_pgoff(inode, &map[i],
|
|
whence == SEEK_HOLE ? HOLE_OFF : DATA_OFF,
|
|
&offset))
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We only received one extent out of the two requested. This
|
|
* means we've hit EOF and didn't find what we are looking for.
|
|
*/
|
|
if (nmap == 1) {
|
|
/*
|
|
* If we were looking for a hole, set offset to
|
|
* the end of the file (i.e., there is an implicit
|
|
* hole at the end of any file).
|
|
*/
|
|
if (whence == SEEK_HOLE) {
|
|
offset = end;
|
|
break;
|
|
}
|
|
/*
|
|
* If we were looking for data, it's nowhere to be found
|
|
*/
|
|
ASSERT(whence == SEEK_DATA);
|
|
error = -ENXIO;
|
|
goto out_error;
|
|
}
|
|
|
|
ASSERT(i > 1);
|
|
|
|
/*
|
|
* Nothing was found, proceed to the next round of search
|
|
* if the next reading offset is not at or beyond EOF.
|
|
*/
|
|
fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
|
|
start = XFS_FSB_TO_B(mp, fsbno);
|
|
if (start >= end) {
|
|
if (whence == SEEK_HOLE) {
|
|
offset = end;
|
|
break;
|
|
}
|
|
ASSERT(whence == SEEK_DATA);
|
|
error = -ENXIO;
|
|
goto out_error;
|
|
}
|
|
}
|
|
|
|
out:
|
|
/*
|
|
* If at this point we have found the hole we wanted, the returned
|
|
* offset may be bigger than the file size as it may be aligned to
|
|
* page boundary for unwritten extents. We need to deal with this
|
|
* situation in particular.
|
|
*/
|
|
if (whence == SEEK_HOLE)
|
|
offset = min_t(loff_t, offset, end);
|
|
|
|
return offset;
|
|
|
|
out_error:
|
|
return error;
|
|
}
|
|
|
|
STATIC loff_t
|
|
xfs_seek_hole_data(
|
|
struct file *file,
|
|
loff_t start,
|
|
int whence)
|
|
{
|
|
struct inode *inode = file->f_mapping->host;
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
uint lock;
|
|
loff_t offset, end;
|
|
int error = 0;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(mp))
|
|
return -EIO;
|
|
|
|
lock = xfs_ilock_data_map_shared(ip);
|
|
|
|
end = i_size_read(inode);
|
|
offset = __xfs_seek_hole_data(inode, start, end, whence);
|
|
if (offset < 0) {
|
|
error = offset;
|
|
goto out_unlock;
|
|
}
|
|
|
|
offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
|
|
|
|
out_unlock:
|
|
xfs_iunlock(ip, lock);
|
|
|
|
if (error)
|
|
return error;
|
|
return offset;
|
|
}
|
|
|
|
STATIC loff_t
|
|
xfs_file_llseek(
|
|
struct file *file,
|
|
loff_t offset,
|
|
int whence)
|
|
{
|
|
switch (whence) {
|
|
case SEEK_END:
|
|
case SEEK_CUR:
|
|
case SEEK_SET:
|
|
return generic_file_llseek(file, offset, whence);
|
|
case SEEK_HOLE:
|
|
case SEEK_DATA:
|
|
return xfs_seek_hole_data(file, offset, whence);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Locking for serialisation of IO during page faults. This results in a lock
|
|
* ordering of:
|
|
*
|
|
* mmap_sem (MM)
|
|
* sb_start_pagefault(vfs, freeze)
|
|
* i_mmaplock (XFS - truncate serialisation)
|
|
* page_lock (MM)
|
|
* i_lock (XFS - extent map serialisation)
|
|
*/
|
|
|
|
/*
|
|
* mmap()d file has taken write protection fault and is being made writable. We
|
|
* can set the page state up correctly for a writable page, which means we can
|
|
* do correct delalloc accounting (ENOSPC checking!) and unwritten extent
|
|
* mapping.
|
|
*/
|
|
STATIC int
|
|
xfs_filemap_page_mkwrite(
|
|
struct vm_fault *vmf)
|
|
{
|
|
struct inode *inode = file_inode(vmf->vma->vm_file);
|
|
int ret;
|
|
|
|
trace_xfs_filemap_page_mkwrite(XFS_I(inode));
|
|
|
|
sb_start_pagefault(inode->i_sb);
|
|
file_update_time(vmf->vma->vm_file);
|
|
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
|
|
|
|
if (IS_DAX(inode)) {
|
|
ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
|
|
} else {
|
|
ret = iomap_page_mkwrite(vmf, &xfs_iomap_ops);
|
|
ret = block_page_mkwrite_return(ret);
|
|
}
|
|
|
|
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
|
|
sb_end_pagefault(inode->i_sb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_filemap_fault(
|
|
struct vm_fault *vmf)
|
|
{
|
|
struct inode *inode = file_inode(vmf->vma->vm_file);
|
|
int ret;
|
|
|
|
trace_xfs_filemap_fault(XFS_I(inode));
|
|
|
|
/* DAX can shortcut the normal fault path on write faults! */
|
|
if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(inode))
|
|
return xfs_filemap_page_mkwrite(vmf);
|
|
|
|
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
|
|
if (IS_DAX(inode))
|
|
ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
|
|
else
|
|
ret = filemap_fault(vmf);
|
|
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Similar to xfs_filemap_fault(), the DAX fault path can call into here on
|
|
* both read and write faults. Hence we need to handle both cases. There is no
|
|
* ->huge_mkwrite callout for huge pages, so we have a single function here to
|
|
* handle both cases here. @flags carries the information on the type of fault
|
|
* occuring.
|
|
*/
|
|
STATIC int
|
|
xfs_filemap_huge_fault(
|
|
struct vm_fault *vmf,
|
|
enum page_entry_size pe_size)
|
|
{
|
|
struct inode *inode = file_inode(vmf->vma->vm_file);
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
int ret;
|
|
|
|
if (!IS_DAX(inode))
|
|
return VM_FAULT_FALLBACK;
|
|
|
|
trace_xfs_filemap_huge_fault(ip);
|
|
|
|
if (vmf->flags & FAULT_FLAG_WRITE) {
|
|
sb_start_pagefault(inode->i_sb);
|
|
file_update_time(vmf->vma->vm_file);
|
|
}
|
|
|
|
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
|
|
ret = dax_iomap_fault(vmf, pe_size, &xfs_iomap_ops);
|
|
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
|
|
|
|
if (vmf->flags & FAULT_FLAG_WRITE)
|
|
sb_end_pagefault(inode->i_sb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* pfn_mkwrite was originally inteneded to ensure we capture time stamp
|
|
* updates on write faults. In reality, it's need to serialise against
|
|
* truncate similar to page_mkwrite. Hence we cycle the XFS_MMAPLOCK_SHARED
|
|
* to ensure we serialise the fault barrier in place.
|
|
*/
|
|
static int
|
|
xfs_filemap_pfn_mkwrite(
|
|
struct vm_fault *vmf)
|
|
{
|
|
|
|
struct inode *inode = file_inode(vmf->vma->vm_file);
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
int ret = VM_FAULT_NOPAGE;
|
|
loff_t size;
|
|
|
|
trace_xfs_filemap_pfn_mkwrite(ip);
|
|
|
|
sb_start_pagefault(inode->i_sb);
|
|
file_update_time(vmf->vma->vm_file);
|
|
|
|
/* check if the faulting page hasn't raced with truncate */
|
|
xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
|
|
size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
if (vmf->pgoff >= size)
|
|
ret = VM_FAULT_SIGBUS;
|
|
else if (IS_DAX(inode))
|
|
ret = dax_pfn_mkwrite(vmf);
|
|
xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
|
|
sb_end_pagefault(inode->i_sb);
|
|
return ret;
|
|
|
|
}
|
|
|
|
static const struct vm_operations_struct xfs_file_vm_ops = {
|
|
.fault = xfs_filemap_fault,
|
|
.huge_fault = xfs_filemap_huge_fault,
|
|
.map_pages = filemap_map_pages,
|
|
.page_mkwrite = xfs_filemap_page_mkwrite,
|
|
.pfn_mkwrite = xfs_filemap_pfn_mkwrite,
|
|
};
|
|
|
|
STATIC int
|
|
xfs_file_mmap(
|
|
struct file *filp,
|
|
struct vm_area_struct *vma)
|
|
{
|
|
file_accessed(filp);
|
|
vma->vm_ops = &xfs_file_vm_ops;
|
|
if (IS_DAX(file_inode(filp)))
|
|
vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
|
|
return 0;
|
|
}
|
|
|
|
const struct file_operations xfs_file_operations = {
|
|
.llseek = xfs_file_llseek,
|
|
.read_iter = xfs_file_read_iter,
|
|
.write_iter = xfs_file_write_iter,
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.unlocked_ioctl = xfs_file_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = xfs_file_compat_ioctl,
|
|
#endif
|
|
.mmap = xfs_file_mmap,
|
|
.open = xfs_file_open,
|
|
.release = xfs_file_release,
|
|
.fsync = xfs_file_fsync,
|
|
.get_unmapped_area = thp_get_unmapped_area,
|
|
.fallocate = xfs_file_fallocate,
|
|
.clone_file_range = xfs_file_clone_range,
|
|
.dedupe_file_range = xfs_file_dedupe_range,
|
|
};
|
|
|
|
const struct file_operations xfs_dir_file_operations = {
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.open = xfs_dir_open,
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.read = generic_read_dir,
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.iterate_shared = xfs_file_readdir,
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.llseek = generic_file_llseek,
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.unlocked_ioctl = xfs_file_ioctl,
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#ifdef CONFIG_COMPAT
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.compat_ioctl = xfs_file_compat_ioctl,
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#endif
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.fsync = xfs_dir_fsync,
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};
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