From: Jan Kara <jack@suse.cz>
To: Zhang Yi <yi.z.zhang@linux.intel.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-nvdimm@lists.01.org, pbonzini@redhat.com,
dan.j.williams@intel.com, jack@suse.cz, hch@lst.de,
yu.c.zhang@intel.com, linux-mm@kvack.org, rkrcmar@redhat.com,
yi.z.zhang@intel.com
Subject: Re: [PATCH V2 3/4] mm: add a function to differentiate the pages is from DAX device memory
Date: Tue, 7 Aug 2018 11:13:57 +0200 [thread overview]
Message-ID: <20180807091357.zxanrttlp3ml7mq2@quack2.suse.cz> (raw)
In-Reply-To: <a0d220839ce0414f13e9394dffcd9abe8689dafe.1531241281.git.yi.z.zhang@linux.intel.com>
On Wed 11-07-18 01:03:51, Zhang Yi wrote:
> DAX driver hotplug the device memory and move it to memory zone, these
> pages will be marked reserved flag, however, some other kernel componet
> will misconceive these pages are reserved mmio (ex: we map these dev_dax
> or fs_dax pages to kvm for DIMM/NVDIMM backend). Together with the type
> MEMORY_DEVICE_FS_DAX, we can use is_dax_page() to differentiate the pages
> is DAX device memory or not.
>
> Signed-off-by: Zhang Yi <yi.z.zhang@linux.intel.com>
> Signed-off-by: Zhang Yu <yu.c.zhang@linux.intel.com>
The patch looks OK to me but I don't really feel too confident about this
part of the kernel... But feel free to add my:
Acked-by: Jan Kara <jack@suse.cz>
Honza
> ---
> include/linux/mm.h | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 6e19265..9f0f690 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -856,6 +856,13 @@ static inline bool is_device_public_page(const struct page *page)
> page->pgmap->type == MEMORY_DEVICE_PUBLIC;
> }
>
> +static inline bool is_dax_page(const struct page *page)
> +{
> + return is_zone_device_page(page) &&
> + (page->pgmap->type == MEMORY_DEVICE_FS_DAX ||
> + page->pgmap->type == MEMORY_DEVICE_DEV_DAX);
> +}
> +
> #else /* CONFIG_DEV_PAGEMAP_OPS */
> static inline void dev_pagemap_get_ops(void)
> {
> @@ -879,6 +886,11 @@ static inline bool is_device_public_page(const struct page *page)
> {
> return false;
> }
> +
> +static inline bool is_dax_page(const struct page *page)
> +{
> + return false;
> +}
> #endif /* CONFIG_DEV_PAGEMAP_OPS */
>
> static inline void get_page(struct page *page)
> --
> 2.7.4
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
next prev parent reply other threads:[~2018-08-07 9:14 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-10 17:01 [PATCH V2 0/4] Fix kvm misconceives NVDIMM pages as reserved mmio Zhang Yi
2018-07-10 17:01 ` [PATCH V2 1/4] kvm: remove redundant reserved page check Zhang Yi
2018-07-10 17:01 ` [PATCH V2 2/4] mm: introduce memory type MEMORY_DEVICE_DEV_DAX Zhang Yi
2018-08-07 9:11 ` Jan Kara
2018-08-08 9:22 ` Zhang,Yi
2018-07-10 17:02 ` [PATCH V2 3/4] mm: add a function to differentiate the pages is from DAX device memory Zhang Yi
2018-07-10 17:03 ` Zhang Yi
2018-08-07 9:13 ` Jan Kara [this message]
2018-07-10 17:04 ` [PATCH V2 4/4] kvm: add a check if pfn is from NVDIMM pmem Zhang Yi
2018-07-13 14:29 ` [PATCH V2 0/4] Fix kvm misconceives NVDIMM pages as reserved mmio Zhang,Yi
2018-07-20 14:11 ` Zhang,Yi
2018-07-20 8:32 ` Paolo Bonzini
2018-07-20 16:24 ` Zhang,Yi
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=20180807091357.zxanrttlp3ml7mq2@quack2.suse.cz \
--to=jack@suse.cz \
--cc=dan.j.williams@intel.com \
--cc=hch@lst.de \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nvdimm@lists.01.org \
--cc=pbonzini@redhat.com \
--cc=rkrcmar@redhat.com \
--cc=yi.z.zhang@intel.com \
--cc=yi.z.zhang@linux.intel.com \
--cc=yu.c.zhang@intel.com \
/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).