From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
jack@suse.cz, david@fromorbit.com, willy@infradead.org,
hch@lst.de, kilobyte@angband.pl, dsterba@suse.cz,
nborisov@suse.com, linux-nvdimm@lists.01.org,
Goldwyn Rodrigues <rgoldwyn@suse.com>
Subject: Re: [PATCH 14/18] dax: memcpy before zeroing range
Date: Wed, 17 Apr 2019 08:45:04 -0700 [thread overview]
Message-ID: <20190417154504.GC4740@magnolia> (raw)
In-Reply-To: <20190416164154.30390-15-rgoldwyn@suse.de>
On Tue, Apr 16, 2019 at 11:41:50AM -0500, Goldwyn Rodrigues wrote:
> From: Goldwyn Rodrigues <rgoldwyn@suse.com>
>
> However, this needed more iomap fields, so it was easier
> to pass iomap and compute inside the function rather
> than passing a log of arguments.
>
> Note, there is subtle difference between iomap_sector and
> dax_iomap_sector(). Can we replace dax_iomap_sector with
> iomap_sector()? It would need pos & PAGE_MASK though or else
> bdev_dax_pgoff() return -EINVAL.
>
> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
> ---
> fs/dax.c | 14 ++++++++++----
> fs/iomap.c | 9 +--------
> include/linux/dax.h | 11 +++++------
> include/linux/iomap.h | 6 ++++++
> 4 files changed, 22 insertions(+), 18 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index abbe4a79f219..af94909640ea 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -1055,11 +1055,15 @@ static bool dax_range_is_aligned(struct block_device *bdev,
> return true;
> }
>
> -int __dax_zero_page_range(struct block_device *bdev,
> - struct dax_device *dax_dev, sector_t sector,
> - unsigned int offset, unsigned int size)
> +int __dax_zero_page_range(struct iomap *iomap, loff_t pos,
> + unsigned int offset, unsigned int size)
> {
> - if (dax_range_is_aligned(bdev, offset, size)) {
> + sector_t sector = dax_iomap_sector(iomap, pos & PAGE_MASK);
> + struct block_device *bdev = iomap->bdev;
> + struct dax_device *dax_dev = iomap->dax_dev;
> +
> + if (!(iomap->type == IOMAP_DAX_COW) &&
> + dax_range_is_aligned(bdev, offset, size)) {
> sector_t start_sector = sector + (offset >> 9);
>
> return blkdev_issue_zeroout(bdev, start_sector,
> @@ -1079,6 +1083,8 @@ int __dax_zero_page_range(struct block_device *bdev,
> dax_read_unlock(id);
> return rc;
> }
> + if (iomap->type == IOMAP_DAX_COW)
> + memcpy(iomap->inline_data, kaddr, offset);
I'm confused, why are we copying into the source page before zeroing
some part of the dax device?
> memset(kaddr + offset, 0, size);
> dax_flush(dax_dev, kaddr + offset, size);
> dax_read_unlock(id);
> diff --git a/fs/iomap.c b/fs/iomap.c
> index abdd18e404f8..90698c854883 100644
> --- a/fs/iomap.c
> +++ b/fs/iomap.c
> @@ -98,12 +98,6 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags,
> return written ? written : ret;
> }
>
> -static sector_t
> -iomap_sector(struct iomap *iomap, loff_t pos)
> -{
> - return (iomap->addr + pos - iomap->offset) >> SECTOR_SHIFT;
> -}
> -
> static struct iomap_page *
> iomap_page_create(struct inode *inode, struct page *page)
> {
> @@ -990,8 +984,7 @@ static int iomap_zero(struct inode *inode, loff_t pos, unsigned offset,
> static int iomap_dax_zero(loff_t pos, unsigned offset, unsigned bytes,
> struct iomap *iomap)
> {
> - return __dax_zero_page_range(iomap->bdev, iomap->dax_dev,
> - iomap_sector(iomap, pos & PAGE_MASK), offset, bytes);
> + return __dax_zero_page_range(iomap, pos, offset, bytes);
> }
>
> static loff_t
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index a11bc7b1f526..892c478d7073 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -9,6 +9,7 @@
>
> typedef unsigned long dax_entry_t;
>
> +struct iomap;
> struct iomap_ops;
> struct dax_device;
> struct dax_operations {
> @@ -161,13 +162,11 @@ int dax_file_range_compare(struct inode *src, loff_t srcoff, struct inode *dest,
> loff_t destoff, loff_t len, bool *is_same, const struct iomap_ops *ops);
>
> #ifdef CONFIG_FS_DAX
> -int __dax_zero_page_range(struct block_device *bdev,
> - struct dax_device *dax_dev, sector_t sector,
> - unsigned int offset, unsigned int length);
> +int __dax_zero_page_range(struct iomap *iomap, loff_t pos,
> + unsigned int offset, unsigned int size);
> #else
> -static inline int __dax_zero_page_range(struct block_device *bdev,
> - struct dax_device *dax_dev, sector_t sector,
> - unsigned int offset, unsigned int length)
> +static inline int __dax_zero_page_range(struct iomap *iomap, loff_t pos,
> + unsigned int offset, unsigned int size)
> {
> return -ENXIO;
> }
> diff --git a/include/linux/iomap.h b/include/linux/iomap.h
> index 6e885c5a38a3..3a803566dea1 100644
> --- a/include/linux/iomap.h
> +++ b/include/linux/iomap.h
> @@ -7,6 +7,7 @@
> #include <linux/mm.h>
> #include <linux/types.h>
> #include <linux/mm_types.h>
> +#include <linux/blkdev.h>
>
> struct address_space;
> struct fiemap_extent_info;
> @@ -120,6 +121,11 @@ static inline struct iomap_page *to_iomap_page(struct page *page)
> return NULL;
> }
>
> +static inline sector_t iomap_sector(struct iomap *iomap, loff_t pos)
> +{
> + return (iomap->addr + pos - iomap->offset) >> SECTOR_SHIFT;
Why the double indent?
--D
> +}
> +
> ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from,
> const struct iomap_ops *ops);
> int iomap_readpage(struct page *page, const struct iomap_ops *ops);
> --
> 2.16.4
>
next prev parent reply other threads:[~2019-04-17 15:46 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-16 16:41 [PATCH v3 00/18] btrfs dax support Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 01/18] btrfs: create a mount option for dax Goldwyn Rodrigues
2019-04-16 16:52 ` Dan Williams
2019-04-16 16:41 ` [PATCH 02/18] btrfs: Carve out btrfs_get_extent_map_write() out of btrfs_get_blocks_write() Goldwyn Rodrigues
2019-04-16 23:45 ` Elliott, Robert (Servers)
2019-04-16 16:41 ` [PATCH 03/18] btrfs: basic dax read Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 04/18] dax: Introduce IOMAP_DAX_COW to CoW edges during writes Goldwyn Rodrigues
2019-04-17 16:46 ` Darrick J. Wong
2019-04-16 16:41 ` [PATCH 05/18] btrfs: return whether extent is nocow or not Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 06/18] btrfs: Rename __endio_write_update_ordered() to btrfs_update_ordered_extent() Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 07/18] btrfs: add dax write support Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 08/18] dax: memcpy page in case of IOMAP_DAX_COW for mmap faults Goldwyn Rodrigues
2019-04-17 16:52 ` Darrick J. Wong
2019-04-16 16:41 ` [PATCH 09/18] btrfs: Add dax specific address_space_operations Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 10/18] dax: replace mmap entry in case of CoW Goldwyn Rodrigues
2019-04-17 15:24 ` Darrick J. Wong
2019-04-16 16:41 ` [PATCH 11/18] btrfs: add dax mmap support Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 12/18] btrfs: allow MAP_SYNC mmap Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 13/18] fs: dedup file range to use a compare function Goldwyn Rodrigues
2019-04-17 15:36 ` Darrick J. Wong
2019-04-16 16:41 ` [PATCH 14/18] dax: memcpy before zeroing range Goldwyn Rodrigues
2019-04-17 15:45 ` Darrick J. Wong [this message]
2019-04-17 16:39 ` Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 15/18] btrfs: handle dax page zeroing Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 16/18] btrfs: Writeprotect mmap pages on snapshot Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 17/18] btrfs: Disable dax-based defrag and send Goldwyn Rodrigues
2019-04-16 16:41 ` [PATCH 18/18] btrfs: trace functions for btrfs_iomap_begin/end Goldwyn Rodrigues
2019-04-17 16:49 ` [PATCH v3 00/18] btrfs dax support Adam Borowski
2019-04-29 17:26 [PATCH v4 " Goldwyn Rodrigues
2019-04-29 17:26 ` [PATCH 14/18] dax: memcpy before zeroing range Goldwyn Rodrigues
2019-05-21 17:27 ` Darrick J. Wong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190417154504.GC4740@magnolia \
--to=darrick.wong@oracle.com \
--cc=david@fromorbit.com \
--cc=dsterba@suse.cz \
--cc=hch@lst.de \
--cc=jack@suse.cz \
--cc=kilobyte@angband.pl \
--cc=linux-btrfs@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-nvdimm@lists.01.org \
--cc=nborisov@suse.com \
--cc=rgoldwyn@suse.com \
--cc=rgoldwyn@suse.de \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).