Re: [PATCH] fs: clean up usage of noop_dirty_folio
On Mon, Aug 21, 2023 at 01:20:33PM +0100, Matthew Wilcox wrote: > I was hoping Christoph would weigh in ;-) I don't have a strong I've enjoyed 2 weeks of almost uninterrupted vacation. I agree with this patch and also your incremental improvements.
Re: [PATCH] fs: clean up usage of noop_dirty_folio
On Mon, Aug 21, 2023 at 01:16:43PM +0200, Jan Kara wrote:
> On Sat 19-08-23 20:42:25, Xueshi Hu wrote:
> > In folio_mark_dirty(), it will automatically fallback to
> > noop_dirty_folio() if a_ops->dirty_folio is not registered.
> >
> > As anon_aops, dev_dax_aops and fb_deferred_io_aops becames empty, remove
> > them too.
> >
> > Signed-off-by: Xueshi Hu
>
> Yeah, looks sensible to me but for some callbacks we are oscilating between
> all users having to provide some callback and providing some default
> behavior for NULL callback. I don't have a strong opinion either way so
> feel free to add:
>
> Reviewed-by: Jan Kara
>
> But I guess let's see what Matthew thinks about this and what plans he has
> so that we don't switch back again in the near future. Matthew?
I was hoping Christoph would weigh in ;-) I don't have a strong
feeling here, but it seems to me that a NULL ->dirty_folio() should mean
"do the noop thing" rather than "do the buffer_head thing" or "do the
filemap thing". In 0af573780b0b, the buffer_head default was removed.
I think enough time has passed that we're OK to change what a NULL
->dirty_folio means (plus we also changed the name of ->set_page_dirty()
to ->dirty_folio())
So Ack to the concept. One minor change I'd request:
-bool noop_dirty_folio(struct address_space *mapping, struct folio *folio)
+static bool noop_dirty_folio(struct address_space *mapping, struct folio
*folio)
{
if (!folio_test_dirty(folio))
return !folio_test_set_dirty(folio);
return false;
}
-EXPORT_SYMBOL(noop_dirty_folio);
Please inline this into folio_mark_dirty() instead of calling it.
Re: [PATCH] fs: clean up usage of noop_dirty_folio
On Sat 19-08-23 20:42:25, Xueshi Hu wrote:
> In folio_mark_dirty(), it will automatically fallback to
> noop_dirty_folio() if a_ops->dirty_folio is not registered.
>
> As anon_aops, dev_dax_aops and fb_deferred_io_aops becames empty, remove
> them too.
>
> Signed-off-by: Xueshi Hu
Yeah, looks sensible to me but for some callbacks we are oscilating between
all users having to provide some callback and providing some default
behavior for NULL callback. I don't have a strong opinion either way so
feel free to add:
Reviewed-by: Jan Kara
But I guess let's see what Matthew thinks about this and what plans he has
so that we don't switch back again in the near future. Matthew?
Honza
> ---
> drivers/dax/device.c| 5 -
> drivers/video/fbdev/core/fb_defio.c | 5 -
> fs/aio.c| 1 -
> fs/ext2/inode.c | 1 -
> fs/ext4/inode.c | 1 -
> fs/fuse/dax.c | 1 -
> fs/hugetlbfs/inode.c| 1 -
> fs/libfs.c | 5 -
> fs/xfs/xfs_aops.c | 1 -
> include/linux/pagemap.h | 1 -
> mm/page-writeback.c | 6 +++---
> mm/secretmem.c | 1 -
> mm/shmem.c | 1 -
> mm/swap_state.c | 1 -
> 14 files changed, 3 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/dax/device.c b/drivers/dax/device.c
> index 30665a3ff6ea..018aa9f88ec7 100644
> --- a/drivers/dax/device.c
> +++ b/drivers/dax/device.c
> @@ -345,10 +345,6 @@ static unsigned long dax_get_unmapped_area(struct file
> *filp,
> return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
> }
>
> -static const struct address_space_operations dev_dax_aops = {
> - .dirty_folio= noop_dirty_folio,
> -};
> -
> static int dax_open(struct inode *inode, struct file *filp)
> {
> struct dax_device *dax_dev = inode_dax(inode);
> @@ -358,7 +354,6 @@ static int dax_open(struct inode *inode, struct file
> *filp)
> dev_dbg(_dax->dev, "trace\n");
> inode->i_mapping = __dax_inode->i_mapping;
> inode->i_mapping->host = __dax_inode;
> - inode->i_mapping->a_ops = _dax_aops;
> filp->f_mapping = inode->i_mapping;
> filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
> filp->f_sb_err = file_sample_sb_err(filp);
> diff --git a/drivers/video/fbdev/core/fb_defio.c
> b/drivers/video/fbdev/core/fb_defio.c
> index 274f5d0fa247..08be3592281f 100644
> --- a/drivers/video/fbdev/core/fb_defio.c
> +++ b/drivers/video/fbdev/core/fb_defio.c
> @@ -221,10 +221,6 @@ static const struct vm_operations_struct
> fb_deferred_io_vm_ops = {
> .page_mkwrite = fb_deferred_io_mkwrite,
> };
>
> -static const struct address_space_operations fb_deferred_io_aops = {
> - .dirty_folio= noop_dirty_folio,
> -};
> -
> int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
> {
> vma->vm_ops = _deferred_io_vm_ops;
> @@ -307,7 +303,6 @@ void fb_deferred_io_open(struct fb_info *info,
> {
> struct fb_deferred_io *fbdefio = info->fbdefio;
>
> - file->f_mapping->a_ops = _deferred_io_aops;
> fbdefio->open_count++;
> }
> EXPORT_SYMBOL_GPL(fb_deferred_io_open);
> diff --git a/fs/aio.c b/fs/aio.c
> index 77e33619de40..4cf386f9cb1c 100644
> --- a/fs/aio.c
> +++ b/fs/aio.c
> @@ -484,7 +484,6 @@ static int aio_migrate_folio(struct address_space
> *mapping, struct folio *dst,
> #endif
>
> static const struct address_space_operations aio_ctx_aops = {
> - .dirty_folio= noop_dirty_folio,
> .migrate_folio = aio_migrate_folio,
> };
>
> diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
> index 75983215c7a1..ce191bdf1c78 100644
> --- a/fs/ext2/inode.c
> +++ b/fs/ext2/inode.c
> @@ -971,7 +971,6 @@ const struct address_space_operations ext2_aops = {
> static const struct address_space_operations ext2_dax_aops = {
> .writepages = ext2_dax_writepages,
> .direct_IO = noop_direct_IO,
> - .dirty_folio= noop_dirty_folio,
> };
>
> /*
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 43775a6ca505..67c1710c01b0 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -3561,7 +3561,6 @@ static const struct address_space_operations
> ext4_da_aops = {
> static const struct address_space_operations ext4_dax_aops = {
> .writepages = ext4_dax_writepages,
> .direct_IO = noop_direct_IO,
> - .dirty_folio= noop_dirty_folio,
> .bmap = ext4_bmap,
> .swap_activate = ext4_iomap_swap_activate,
> };
> diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
> index 8e74f278a3f6..50ca767cbd5e 100644
> --- a/fs/fuse/dax.c
> +++ b/fs/fuse/dax.c
> @@ -1326,7 +1326,6 @@ bool fuse_dax_inode_alloc(struct super_block *sb,
> struct fuse_inode *fi)
[PATCH] fs: clean up usage of noop_dirty_folio
In folio_mark_dirty(), it will automatically fallback to
noop_dirty_folio() if a_ops->dirty_folio is not registered.
As anon_aops, dev_dax_aops and fb_deferred_io_aops becames empty, remove
them too.
Signed-off-by: Xueshi Hu
---
drivers/dax/device.c| 5 -
drivers/video/fbdev/core/fb_defio.c | 5 -
fs/aio.c| 1 -
fs/ext2/inode.c | 1 -
fs/ext4/inode.c | 1 -
fs/fuse/dax.c | 1 -
fs/hugetlbfs/inode.c| 1 -
fs/libfs.c | 5 -
fs/xfs/xfs_aops.c | 1 -
include/linux/pagemap.h | 1 -
mm/page-writeback.c | 6 +++---
mm/secretmem.c | 1 -
mm/shmem.c | 1 -
mm/swap_state.c | 1 -
14 files changed, 3 insertions(+), 28 deletions(-)
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 30665a3ff6ea..018aa9f88ec7 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -345,10 +345,6 @@ static unsigned long dax_get_unmapped_area(struct file
*filp,
return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
}
-static const struct address_space_operations dev_dax_aops = {
- .dirty_folio= noop_dirty_folio,
-};
-
static int dax_open(struct inode *inode, struct file *filp)
{
struct dax_device *dax_dev = inode_dax(inode);
@@ -358,7 +354,6 @@ static int dax_open(struct inode *inode, struct file *filp)
dev_dbg(_dax->dev, "trace\n");
inode->i_mapping = __dax_inode->i_mapping;
inode->i_mapping->host = __dax_inode;
- inode->i_mapping->a_ops = _dax_aops;
filp->f_mapping = inode->i_mapping;
filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
filp->f_sb_err = file_sample_sb_err(filp);
diff --git a/drivers/video/fbdev/core/fb_defio.c
b/drivers/video/fbdev/core/fb_defio.c
index 274f5d0fa247..08be3592281f 100644
--- a/drivers/video/fbdev/core/fb_defio.c
+++ b/drivers/video/fbdev/core/fb_defio.c
@@ -221,10 +221,6 @@ static const struct vm_operations_struct
fb_deferred_io_vm_ops = {
.page_mkwrite = fb_deferred_io_mkwrite,
};
-static const struct address_space_operations fb_deferred_io_aops = {
- .dirty_folio= noop_dirty_folio,
-};
-
int fb_deferred_io_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
vma->vm_ops = _deferred_io_vm_ops;
@@ -307,7 +303,6 @@ void fb_deferred_io_open(struct fb_info *info,
{
struct fb_deferred_io *fbdefio = info->fbdefio;
- file->f_mapping->a_ops = _deferred_io_aops;
fbdefio->open_count++;
}
EXPORT_SYMBOL_GPL(fb_deferred_io_open);
diff --git a/fs/aio.c b/fs/aio.c
index 77e33619de40..4cf386f9cb1c 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -484,7 +484,6 @@ static int aio_migrate_folio(struct address_space *mapping,
struct folio *dst,
#endif
static const struct address_space_operations aio_ctx_aops = {
- .dirty_folio= noop_dirty_folio,
.migrate_folio = aio_migrate_folio,
};
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 75983215c7a1..ce191bdf1c78 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -971,7 +971,6 @@ const struct address_space_operations ext2_aops = {
static const struct address_space_operations ext2_dax_aops = {
.writepages = ext2_dax_writepages,
.direct_IO = noop_direct_IO,
- .dirty_folio= noop_dirty_folio,
};
/*
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 43775a6ca505..67c1710c01b0 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3561,7 +3561,6 @@ static const struct address_space_operations ext4_da_aops
= {
static const struct address_space_operations ext4_dax_aops = {
.writepages = ext4_dax_writepages,
.direct_IO = noop_direct_IO,
- .dirty_folio= noop_dirty_folio,
.bmap = ext4_bmap,
.swap_activate = ext4_iomap_swap_activate,
};
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index 8e74f278a3f6..50ca767cbd5e 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -1326,7 +1326,6 @@ bool fuse_dax_inode_alloc(struct super_block *sb, struct
fuse_inode *fi)
static const struct address_space_operations fuse_dax_file_aops = {
.writepages = fuse_dax_writepages,
.direct_IO = noop_direct_IO,
- .dirty_folio= noop_dirty_folio,
};
static bool fuse_should_enable_dax(struct inode *inode, unsigned int flags)
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 7b17ccfa039d..5404286f0c13 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -1266,7 +1266,6 @@ static void hugetlbfs_destroy_inode(struct inode *inode)
static const struct address_space_operations hugetlbfs_aops = {
.write_begin= hugetlbfs_write_begin,
.write_end = hugetlbfs_write_end,
- .dirty_folio
