| Message ID | 20210915104501.4146910-9-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fsdax,xfs: Add reflink&dedupe support for fsdax | expand |
On Wed, Sep 15, 2021 at 06:45:01PM +0800, Shiyang Ruan wrote: > Introduce xfs_mmaplock_two_inodes_and_break_dax_layout() for dax files > who are going to be deduped. After that, call compare range function > only when files are both DAX or not. > > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> > Reviewed-by: Darrick J. Wong <djwong@kernel.org> > Reviewed-by: Christoph Hellwig <hch@lst.de> > --- > fs/xfs/xfs_file.c | 2 +- > fs/xfs/xfs_inode.c | 80 +++++++++++++++++++++++++++++++++++++++++--- > fs/xfs/xfs_inode.h | 1 + > fs/xfs/xfs_reflink.c | 4 +-- > 4 files changed, 80 insertions(+), 7 deletions(-) > > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c > index 2ef1930374d2..c3061723613c 100644 > --- a/fs/xfs/xfs_file.c > +++ b/fs/xfs/xfs_file.c > @@ -846,7 +846,7 @@ xfs_wait_dax_page( > xfs_ilock(ip, XFS_MMAPLOCK_EXCL); > } > > -static int > +int > xfs_break_dax_layouts( > struct inode *inode, > bool *retry) > diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c > index a4f6f034fb81..bdc084cdbf46 100644 > --- a/fs/xfs/xfs_inode.c > +++ b/fs/xfs/xfs_inode.c > @@ -3790,6 +3790,61 @@ xfs_iolock_two_inodes_and_break_layout( > return 0; > } > > +static int > +xfs_mmaplock_two_inodes_and_break_dax_layout( > + struct xfs_inode *ip1, > + struct xfs_inode *ip2) > +{ > + int error, attempts = 0; > + bool retry; > + struct page *page; > + struct xfs_log_item *lp; > + > + if (ip1->i_ino > ip2->i_ino) > + swap(ip1, ip2); > + > +again: > + retry = false; > + /* Lock the first inode */ > + xfs_ilock(ip1, XFS_MMAPLOCK_EXCL); > + error = xfs_break_dax_layouts(VFS_I(ip1), &retry); > + if (error || retry) { > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > + if (error == 0 && retry) > + goto again; > + return error; > + } > + > + if (ip1 == ip2) > + return 0; > + > + /* Nested lock the second inode */ > + lp = &ip1->i_itemp->ili_item; > + if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) { > + if (!xfs_ilock_nowait(ip2, > + xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1))) { > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > + if ((++attempts % 5) == 0) > + delay(1); /* Don't just spin the CPU */ > + goto again; > + } I suspect we don't need this part for grabbing the MMAPLOCK^W pagecache invalidatelock. The AIL only grabs the ILOCK, never the IOLOCK or the MMAPLOCK. > + } else > + xfs_ilock(ip2, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1)); > + /* > + * We cannot use xfs_break_dax_layouts() directly here because it may > + * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable > + * for this nested lock case. > + */ > + page = dax_layout_busy_page(VFS_I(ip2)->i_mapping); > + if (page && page_ref_count(page) != 1) { Do you think the patch "ext4/xfs: add page refcount helper" would be a good cleanup to head this series? https://lore.kernel.org/linux-xfs/20210913161604.31981-1-alex.sierra@amd.com/T/#m59cf7cd5c0d521ad487fa3a15d31c3865db88bdf The rest of the logic looks ok. --D > + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > + goto again; > + } > + > + return 0; > +} > + > /* > * Lock two inodes so that userspace cannot initiate I/O via file syscalls or > * mmap activity. > @@ -3804,8 +3859,19 @@ xfs_ilock2_io_mmap( > ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2)); > if (ret) > return ret; > - filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, > - VFS_I(ip2)->i_mapping); > + > + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { > + ret = xfs_mmaplock_two_inodes_and_break_dax_layout(ip1, ip2); > + if (ret) { > + inode_unlock(VFS_I(ip2)); > + if (ip1 != ip2) > + inode_unlock(VFS_I(ip1)); > + return ret; > + } > + } else > + filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, > + VFS_I(ip2)->i_mapping); > + > return 0; > } > > @@ -3815,8 +3881,14 @@ xfs_iunlock2_io_mmap( > struct xfs_inode *ip1, > struct xfs_inode *ip2) > { > - filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, > - VFS_I(ip2)->i_mapping); > + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { > + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); > + if (ip1 != ip2) > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > + } else > + filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, > + VFS_I(ip2)->i_mapping); > + > inode_unlock(VFS_I(ip2)); > if (ip1 != ip2) > inode_unlock(VFS_I(ip1)); > diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h > index b21b177832d1..f7e26fe31a26 100644 > --- a/fs/xfs/xfs_inode.h > +++ b/fs/xfs/xfs_inode.h > @@ -472,6 +472,7 @@ enum xfs_prealloc_flags { > > int xfs_update_prealloc_flags(struct xfs_inode *ip, > enum xfs_prealloc_flags flags); > +int xfs_break_dax_layouts(struct inode *inode, bool *retry); > int xfs_break_layouts(struct inode *inode, uint *iolock, > enum layout_break_reason reason); > > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c > index 9d876e268734..3b99c9dfcf0d 100644 > --- a/fs/xfs/xfs_reflink.c > +++ b/fs/xfs/xfs_reflink.c > @@ -1327,8 +1327,8 @@ xfs_reflink_remap_prep( > if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) > goto out_unlock; > > - /* Don't share DAX file data for now. */ > - if (IS_DAX(inode_in) || IS_DAX(inode_out)) > + /* Don't share DAX file data with non-DAX file. */ > + if (IS_DAX(inode_in) != IS_DAX(inode_out)) > goto out_unlock; > > if (!IS_DAX(inode_in)) > -- > 2.33.0 > > >
On 2021/9/16 8:30, Darrick J. Wong wrote: > On Wed, Sep 15, 2021 at 06:45:01PM +0800, Shiyang Ruan wrote: >> Introduce xfs_mmaplock_two_inodes_and_break_dax_layout() for dax files >> who are going to be deduped. After that, call compare range function >> only when files are both DAX or not. >> >> Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> >> Reviewed-by: Darrick J. Wong <djwong@kernel.org> >> Reviewed-by: Christoph Hellwig <hch@lst.de> >> --- >> fs/xfs/xfs_file.c | 2 +- >> fs/xfs/xfs_inode.c | 80 +++++++++++++++++++++++++++++++++++++++++--- >> fs/xfs/xfs_inode.h | 1 + >> fs/xfs/xfs_reflink.c | 4 +-- >> 4 files changed, 80 insertions(+), 7 deletions(-) >> >> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c >> index 2ef1930374d2..c3061723613c 100644 >> --- a/fs/xfs/xfs_file.c >> +++ b/fs/xfs/xfs_file.c >> @@ -846,7 +846,7 @@ xfs_wait_dax_page( >> xfs_ilock(ip, XFS_MMAPLOCK_EXCL); >> } >> >> -static int >> +int >> xfs_break_dax_layouts( >> struct inode *inode, >> bool *retry) >> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c >> index a4f6f034fb81..bdc084cdbf46 100644 >> --- a/fs/xfs/xfs_inode.c >> +++ b/fs/xfs/xfs_inode.c >> @@ -3790,6 +3790,61 @@ xfs_iolock_two_inodes_and_break_layout( >> return 0; >> } >> >> +static int >> +xfs_mmaplock_two_inodes_and_break_dax_layout( >> + struct xfs_inode *ip1, >> + struct xfs_inode *ip2) >> +{ >> + int error, attempts = 0; >> + bool retry; >> + struct page *page; >> + struct xfs_log_item *lp; >> + >> + if (ip1->i_ino > ip2->i_ino) >> + swap(ip1, ip2); >> + >> +again: >> + retry = false; >> + /* Lock the first inode */ >> + xfs_ilock(ip1, XFS_MMAPLOCK_EXCL); >> + error = xfs_break_dax_layouts(VFS_I(ip1), &retry); >> + if (error || retry) { >> + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); >> + if (error == 0 && retry) >> + goto again; >> + return error; >> + } >> + >> + if (ip1 == ip2) >> + return 0; >> + >> + /* Nested lock the second inode */ >> + lp = &ip1->i_itemp->ili_item; >> + if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) { >> + if (!xfs_ilock_nowait(ip2, >> + xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1))) { >> + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); >> + if ((++attempts % 5) == 0) >> + delay(1); /* Don't just spin the CPU */ >> + goto again; >> + } > > I suspect we don't need this part for grabbing the MMAPLOCK^W pagecache > invalidatelock. The AIL only grabs the ILOCK, never the IOLOCK or the > MMAPLOCK. Maybe I have misunderstood this part. What I want is to lock the two inode nestedly. This code is copied from xfs_lock_two_inodes(), which checks this AIL during locking two inode with each of the three kinds of locks. But I also found the recent merged function: filemap_invalidate_lock_two() just locks two inode directly without checking AIL. So, I am not if the AIL check is needed in this case. > >> + } else >> + xfs_ilock(ip2, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1)); >> + /* >> + * We cannot use xfs_break_dax_layouts() directly here because it may >> + * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable >> + * for this nested lock case. >> + */ >> + page = dax_layout_busy_page(VFS_I(ip2)->i_mapping); >> + if (page && page_ref_count(page) != 1) { > > Do you think the patch "ext4/xfs: add page refcount helper" would be a > good cleanup to head this series? > > https://lore.kernel.org/linux-xfs/20210913161604.31981-1-alex.sierra@amd.com/T/#m59cf7cd5c0d521ad487fa3a15d31c3865db88bdf Got it. -- Thanks, Ruan > > The rest of the logic looks ok. > > --D > >> + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); >> + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); >> + goto again; >> + } >> + >> + return 0; >> +} >> + >> /* >> * Lock two inodes so that userspace cannot initiate I/O via file syscalls or >> * mmap activity. >> @@ -3804,8 +3859,19 @@ xfs_ilock2_io_mmap( >> ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2)); >> if (ret) >> return ret; >> - filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, >> - VFS_I(ip2)->i_mapping); >> + >> + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { >> + ret = xfs_mmaplock_two_inodes_and_break_dax_layout(ip1, ip2); >> + if (ret) { >> + inode_unlock(VFS_I(ip2)); >> + if (ip1 != ip2) >> + inode_unlock(VFS_I(ip1)); >> + return ret; >> + } >> + } else >> + filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, >> + VFS_I(ip2)->i_mapping); >> + >> return 0; >> } >> >> @@ -3815,8 +3881,14 @@ xfs_iunlock2_io_mmap( >> struct xfs_inode *ip1, >> struct xfs_inode *ip2) >> { >> - filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, >> - VFS_I(ip2)->i_mapping); >> + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { >> + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); >> + if (ip1 != ip2) >> + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); >> + } else >> + filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, >> + VFS_I(ip2)->i_mapping); >> + >> inode_unlock(VFS_I(ip2)); >> if (ip1 != ip2) >> inode_unlock(VFS_I(ip1)); >> diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h >> index b21b177832d1..f7e26fe31a26 100644 >> --- a/fs/xfs/xfs_inode.h >> +++ b/fs/xfs/xfs_inode.h >> @@ -472,6 +472,7 @@ enum xfs_prealloc_flags { >> >> int xfs_update_prealloc_flags(struct xfs_inode *ip, >> enum xfs_prealloc_flags flags); >> +int xfs_break_dax_layouts(struct inode *inode, bool *retry); >> int xfs_break_layouts(struct inode *inode, uint *iolock, >> enum layout_break_reason reason); >> >> diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c >> index 9d876e268734..3b99c9dfcf0d 100644 >> --- a/fs/xfs/xfs_reflink.c >> +++ b/fs/xfs/xfs_reflink.c >> @@ -1327,8 +1327,8 @@ xfs_reflink_remap_prep( >> if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) >> goto out_unlock; >> >> - /* Don't share DAX file data for now. */ >> - if (IS_DAX(inode_in) || IS_DAX(inode_out)) >> + /* Don't share DAX file data with non-DAX file. */ >> + if (IS_DAX(inode_in) != IS_DAX(inode_out)) >> goto out_unlock; >> >> if (!IS_DAX(inode_in)) >> -- >> 2.33.0 >> >> >>
On Thu, Sep 16, 2021 at 12:01:18PM +0800, Shiyang Ruan wrote: > > > On 2021/9/16 8:30, Darrick J. Wong wrote: > > On Wed, Sep 15, 2021 at 06:45:01PM +0800, Shiyang Ruan wrote: > > > Introduce xfs_mmaplock_two_inodes_and_break_dax_layout() for dax files > > > who are going to be deduped. After that, call compare range function > > > only when files are both DAX or not. > > > > > > Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> > > > Reviewed-by: Darrick J. Wong <djwong@kernel.org> > > > Reviewed-by: Christoph Hellwig <hch@lst.de> > > > --- > > > fs/xfs/xfs_file.c | 2 +- > > > fs/xfs/xfs_inode.c | 80 +++++++++++++++++++++++++++++++++++++++++--- > > > fs/xfs/xfs_inode.h | 1 + > > > fs/xfs/xfs_reflink.c | 4 +-- > > > 4 files changed, 80 insertions(+), 7 deletions(-) > > > > > > diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c > > > index 2ef1930374d2..c3061723613c 100644 > > > --- a/fs/xfs/xfs_file.c > > > +++ b/fs/xfs/xfs_file.c > > > @@ -846,7 +846,7 @@ xfs_wait_dax_page( > > > xfs_ilock(ip, XFS_MMAPLOCK_EXCL); > > > } > > > -static int > > > +int > > > xfs_break_dax_layouts( > > > struct inode *inode, > > > bool *retry) > > > diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c > > > index a4f6f034fb81..bdc084cdbf46 100644 > > > --- a/fs/xfs/xfs_inode.c > > > +++ b/fs/xfs/xfs_inode.c > > > @@ -3790,6 +3790,61 @@ xfs_iolock_two_inodes_and_break_layout( > > > return 0; > > > } > > > +static int > > > +xfs_mmaplock_two_inodes_and_break_dax_layout( > > > + struct xfs_inode *ip1, > > > + struct xfs_inode *ip2) > > > +{ > > > + int error, attempts = 0; > > > + bool retry; > > > + struct page *page; > > > + struct xfs_log_item *lp; > > > + > > > + if (ip1->i_ino > ip2->i_ino) > > > + swap(ip1, ip2); > > > + > > > +again: > > > + retry = false; > > > + /* Lock the first inode */ > > > + xfs_ilock(ip1, XFS_MMAPLOCK_EXCL); > > > + error = xfs_break_dax_layouts(VFS_I(ip1), &retry); > > > + if (error || retry) { > > > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > > > + if (error == 0 && retry) > > > + goto again; > > > + return error; > > > + } > > > + > > > + if (ip1 == ip2) > > > + return 0; > > > + > > > + /* Nested lock the second inode */ > > > + lp = &ip1->i_itemp->ili_item; > > > + if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) { > > > + if (!xfs_ilock_nowait(ip2, > > > + xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1))) { > > > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > > > + if ((++attempts % 5) == 0) > > > + delay(1); /* Don't just spin the CPU */ > > > + goto again; > > > + } > > > > I suspect we don't need this part for grabbing the MMAPLOCK^W pagecache > > invalidatelock. The AIL only grabs the ILOCK, never the IOLOCK or the > > MMAPLOCK. > > Maybe I have misunderstood this part. > > What I want is to lock the two inode nestedly. This code is copied from > xfs_lock_two_inodes(), which checks this AIL during locking two inode with > each of the three kinds of locks. <nod> It's totally reasonable to copy-paste the function you want and change it as needed... > But I also found the recent merged function: filemap_invalidate_lock_two() > just locks two inode directly without checking AIL. So, I am not if the AIL > check is needed in this case. ...especially when even the maintainer is only 99% sure that the AIL checking chunk here can be removed. Anyone else have an opinion? --D > > > > > + } else > > > + xfs_ilock(ip2, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1)); > > > + /* > > > + * We cannot use xfs_break_dax_layouts() directly here because it may > > > + * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable > > > + * for this nested lock case. > > > + */ > > > + page = dax_layout_busy_page(VFS_I(ip2)->i_mapping); > > > + if (page && page_ref_count(page) != 1) { > > > > Do you think the patch "ext4/xfs: add page refcount helper" would be a > > good cleanup to head this series? > > > > https://lore.kernel.org/linux-xfs/20210913161604.31981-1-alex.sierra@amd.com/T/#m59cf7cd5c0d521ad487fa3a15d31c3865db88bdf > > Got it. > > > -- > Thanks, > Ruan > > > > > The rest of the logic looks ok. > > > > --D > > > > > + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); > > > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > > > + goto again; > > > + } > > > + > > > + return 0; > > > +} > > > + > > > /* > > > * Lock two inodes so that userspace cannot initiate I/O via file syscalls or > > > * mmap activity. > > > @@ -3804,8 +3859,19 @@ xfs_ilock2_io_mmap( > > > ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2)); > > > if (ret) > > > return ret; > > > - filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, > > > - VFS_I(ip2)->i_mapping); > > > + > > > + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { > > > + ret = xfs_mmaplock_two_inodes_and_break_dax_layout(ip1, ip2); > > > + if (ret) { > > > + inode_unlock(VFS_I(ip2)); > > > + if (ip1 != ip2) > > > + inode_unlock(VFS_I(ip1)); > > > + return ret; > > > + } > > > + } else > > > + filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, > > > + VFS_I(ip2)->i_mapping); > > > + > > > return 0; > > > } > > > @@ -3815,8 +3881,14 @@ xfs_iunlock2_io_mmap( > > > struct xfs_inode *ip1, > > > struct xfs_inode *ip2) > > > { > > > - filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, > > > - VFS_I(ip2)->i_mapping); > > > + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { > > > + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); > > > + if (ip1 != ip2) > > > + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); > > > + } else > > > + filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, > > > + VFS_I(ip2)->i_mapping); > > > + > > > inode_unlock(VFS_I(ip2)); > > > if (ip1 != ip2) > > > inode_unlock(VFS_I(ip1)); > > > diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h > > > index b21b177832d1..f7e26fe31a26 100644 > > > --- a/fs/xfs/xfs_inode.h > > > +++ b/fs/xfs/xfs_inode.h > > > @@ -472,6 +472,7 @@ enum xfs_prealloc_flags { > > > int xfs_update_prealloc_flags(struct xfs_inode *ip, > > > enum xfs_prealloc_flags flags); > > > +int xfs_break_dax_layouts(struct inode *inode, bool *retry); > > > int xfs_break_layouts(struct inode *inode, uint *iolock, > > > enum layout_break_reason reason); > > > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c > > > index 9d876e268734..3b99c9dfcf0d 100644 > > > --- a/fs/xfs/xfs_reflink.c > > > +++ b/fs/xfs/xfs_reflink.c > > > @@ -1327,8 +1327,8 @@ xfs_reflink_remap_prep( > > > if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) > > > goto out_unlock; > > > - /* Don't share DAX file data for now. */ > > > - if (IS_DAX(inode_in) || IS_DAX(inode_out)) > > > + /* Don't share DAX file data with non-DAX file. */ > > > + if (IS_DAX(inode_in) != IS_DAX(inode_out)) > > > goto out_unlock; > > > if (!IS_DAX(inode_in)) > > > -- > > > 2.33.0 > > > > > > > > > > >
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 2ef1930374d2..c3061723613c 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -846,7 +846,7 @@ xfs_wait_dax_page( xfs_ilock(ip, XFS_MMAPLOCK_EXCL); } -static int +int xfs_break_dax_layouts( struct inode *inode, bool *retry) diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index a4f6f034fb81..bdc084cdbf46 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -3790,6 +3790,61 @@ xfs_iolock_two_inodes_and_break_layout( return 0; } +static int +xfs_mmaplock_two_inodes_and_break_dax_layout( + struct xfs_inode *ip1, + struct xfs_inode *ip2) +{ + int error, attempts = 0; + bool retry; + struct page *page; + struct xfs_log_item *lp; + + if (ip1->i_ino > ip2->i_ino) + swap(ip1, ip2); + +again: + retry = false; + /* Lock the first inode */ + xfs_ilock(ip1, XFS_MMAPLOCK_EXCL); + error = xfs_break_dax_layouts(VFS_I(ip1), &retry); + if (error || retry) { + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); + if (error == 0 && retry) + goto again; + return error; + } + + if (ip1 == ip2) + return 0; + + /* Nested lock the second inode */ + lp = &ip1->i_itemp->ili_item; + if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) { + if (!xfs_ilock_nowait(ip2, + xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1))) { + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); + if ((++attempts % 5) == 0) + delay(1); /* Don't just spin the CPU */ + goto again; + } + } else + xfs_ilock(ip2, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1)); + /* + * We cannot use xfs_break_dax_layouts() directly here because it may + * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable + * for this nested lock case. + */ + page = dax_layout_busy_page(VFS_I(ip2)->i_mapping); + if (page && page_ref_count(page) != 1) { + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); + goto again; + } + + return 0; +} + /* * Lock two inodes so that userspace cannot initiate I/O via file syscalls or * mmap activity. @@ -3804,8 +3859,19 @@ xfs_ilock2_io_mmap( ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2)); if (ret) return ret; - filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, - VFS_I(ip2)->i_mapping); + + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { + ret = xfs_mmaplock_two_inodes_and_break_dax_layout(ip1, ip2); + if (ret) { + inode_unlock(VFS_I(ip2)); + if (ip1 != ip2) + inode_unlock(VFS_I(ip1)); + return ret; + } + } else + filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping, + VFS_I(ip2)->i_mapping); + return 0; } @@ -3815,8 +3881,14 @@ xfs_iunlock2_io_mmap( struct xfs_inode *ip1, struct xfs_inode *ip2) { - filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, - VFS_I(ip2)->i_mapping); + if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) { + xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL); + if (ip1 != ip2) + xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL); + } else + filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping, + VFS_I(ip2)->i_mapping); + inode_unlock(VFS_I(ip2)); if (ip1 != ip2) inode_unlock(VFS_I(ip1)); diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h index b21b177832d1..f7e26fe31a26 100644 --- a/fs/xfs/xfs_inode.h +++ b/fs/xfs/xfs_inode.h @@ -472,6 +472,7 @@ enum xfs_prealloc_flags { int xfs_update_prealloc_flags(struct xfs_inode *ip, enum xfs_prealloc_flags flags); +int xfs_break_dax_layouts(struct inode *inode, bool *retry); int xfs_break_layouts(struct inode *inode, uint *iolock, enum layout_break_reason reason); diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index 9d876e268734..3b99c9dfcf0d 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -1327,8 +1327,8 @@ xfs_reflink_remap_prep( if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) goto out_unlock; - /* Don't share DAX file data for now. */ - if (IS_DAX(inode_in) || IS_DAX(inode_out)) + /* Don't share DAX file data with non-DAX file. */ + if (IS_DAX(inode_in) != IS_DAX(inode_out)) goto out_unlock; if (!IS_DAX(inode_in))