From: Ira Weiny <ira.weiny@intel.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-nvdimm@lists.01.org, virtio-fs@redhat.com,
miklos@szeredi.hu, stefanha@redhat.com, dgilbert@redhat.com,
mst@redhat.com
Subject: Re: [PATCH 02/20] dax: Create a range version of dax_layout_busy_page()
Date: Tue, 10 Mar 2020 08:19:07 -0700 [thread overview]
Message-ID: <20200310151906.GA670549@iweiny-DESK2.sc.intel.com> (raw)
In-Reply-To: <20200304165845.3081-3-vgoyal@redhat.com>
On Wed, Mar 04, 2020 at 11:58:27AM -0500, Vivek Goyal wrote:
>
> + /* If end == 0, all pages from start to till end of file */
> + if (!end) {
> + end_idx = ULONG_MAX;
> + len = 0;
I find this a bit odd to specify end == 0 for ULONG_MAX...
> }
> +EXPORT_SYMBOL_GPL(dax_layout_busy_page_range);
> +
> +/**
> + * dax_layout_busy_page - find first pinned page in @mapping
> + * @mapping: address space to scan for a page with ref count > 1
> + *
> + * DAX requires ZONE_DEVICE mapped pages. These pages are never
> + * 'onlined' to the page allocator so they are considered idle when
> + * page->count == 1. A filesystem uses this interface to determine if
> + * any page in the mapping is busy, i.e. for DMA, or other
> + * get_user_pages() usages.
> + *
> + * It is expected that the filesystem is holding locks to block the
> + * establishment of new mappings in this address_space. I.e. it expects
> + * to be able to run unmap_mapping_range() and subsequently not race
> + * mapping_mapped() becoming true.
> + */
> +struct page *dax_layout_busy_page(struct address_space *mapping)
> +{
> + return dax_layout_busy_page_range(mapping, 0, 0);
... other functions I have seen specify ULONG_MAX here. Which IMO makes this
call site more clear.
Ira
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WARNING: multiple messages have this Message-ID (diff)
From: Ira Weiny <ira.weiny@intel.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-nvdimm@lists.01.org, virtio-fs@redhat.com,
miklos@szeredi.hu, stefanha@redhat.com, dgilbert@redhat.com,
mst@redhat.com
Subject: Re: [PATCH 02/20] dax: Create a range version of dax_layout_busy_page()
Date: Tue, 10 Mar 2020 08:19:07 -0700 [thread overview]
Message-ID: <20200310151906.GA670549@iweiny-DESK2.sc.intel.com> (raw)
In-Reply-To: <20200304165845.3081-3-vgoyal@redhat.com>
On Wed, Mar 04, 2020 at 11:58:27AM -0500, Vivek Goyal wrote:
>
> + /* If end == 0, all pages from start to till end of file */
> + if (!end) {
> + end_idx = ULONG_MAX;
> + len = 0;
I find this a bit odd to specify end == 0 for ULONG_MAX...
> }
> +EXPORT_SYMBOL_GPL(dax_layout_busy_page_range);
> +
> +/**
> + * dax_layout_busy_page - find first pinned page in @mapping
> + * @mapping: address space to scan for a page with ref count > 1
> + *
> + * DAX requires ZONE_DEVICE mapped pages. These pages are never
> + * 'onlined' to the page allocator so they are considered idle when
> + * page->count == 1. A filesystem uses this interface to determine if
> + * any page in the mapping is busy, i.e. for DMA, or other
> + * get_user_pages() usages.
> + *
> + * It is expected that the filesystem is holding locks to block the
> + * establishment of new mappings in this address_space. I.e. it expects
> + * to be able to run unmap_mapping_range() and subsequently not race
> + * mapping_mapped() becoming true.
> + */
> +struct page *dax_layout_busy_page(struct address_space *mapping)
> +{
> + return dax_layout_busy_page_range(mapping, 0, 0);
... other functions I have seen specify ULONG_MAX here. Which IMO makes this
call site more clear.
Ira
WARNING: multiple messages have this Message-ID (diff)
From: Ira Weiny <ira.weiny@intel.com>
To: Vivek Goyal <vgoyal@redhat.com>
Cc: miklos@szeredi.hu, linux-nvdimm@lists.01.org,
linux-kernel@vger.kernel.org, virtio-fs@redhat.com,
mst@redhat.com, linux-fsdevel@vger.kernel.org
Subject: Re: [Virtio-fs] [PATCH 02/20] dax: Create a range version of dax_layout_busy_page()
Date: Tue, 10 Mar 2020 08:19:07 -0700 [thread overview]
Message-ID: <20200310151906.GA670549@iweiny-DESK2.sc.intel.com> (raw)
In-Reply-To: <20200304165845.3081-3-vgoyal@redhat.com>
On Wed, Mar 04, 2020 at 11:58:27AM -0500, Vivek Goyal wrote:
>
> + /* If end == 0, all pages from start to till end of file */
> + if (!end) {
> + end_idx = ULONG_MAX;
> + len = 0;
I find this a bit odd to specify end == 0 for ULONG_MAX...
> }
> +EXPORT_SYMBOL_GPL(dax_layout_busy_page_range);
> +
> +/**
> + * dax_layout_busy_page - find first pinned page in @mapping
> + * @mapping: address space to scan for a page with ref count > 1
> + *
> + * DAX requires ZONE_DEVICE mapped pages. These pages are never
> + * 'onlined' to the page allocator so they are considered idle when
> + * page->count == 1. A filesystem uses this interface to determine if
> + * any page in the mapping is busy, i.e. for DMA, or other
> + * get_user_pages() usages.
> + *
> + * It is expected that the filesystem is holding locks to block the
> + * establishment of new mappings in this address_space. I.e. it expects
> + * to be able to run unmap_mapping_range() and subsequently not race
> + * mapping_mapped() becoming true.
> + */
> +struct page *dax_layout_busy_page(struct address_space *mapping)
> +{
> + return dax_layout_busy_page_range(mapping, 0, 0);
... other functions I have seen specify ULONG_MAX here. Which IMO makes this
call site more clear.
Ira
next prev parent reply other threads:[~2020-03-10 15:19 UTC|newest]
Thread overview: 201+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-04 16:58 [PATCH 00/20] virtiofs: Add DAX support Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 01/20] dax: Modify bdev_dax_pgoff() to handle NULL bdev Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 02/20] dax: Create a range version of dax_layout_busy_page() Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 15:19 ` Ira Weiny [this message]
2020-03-10 15:19 ` [Virtio-fs] " Ira Weiny
2020-03-10 15:19 ` Ira Weiny
2020-03-10 20:29 ` Vivek Goyal
2020-03-10 20:29 ` [Virtio-fs] " Vivek Goyal
2020-03-10 20:29 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 03/20] virtio: Add get_shm_region method Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 10:53 ` Stefan Hajnoczi
2020-03-10 10:53 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-10 10:53 ` Stefan Hajnoczi
2020-03-04 16:58 ` [PATCH 04/20] virtio: Implement get_shm_region for PCI transport Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 11:04 ` Stefan Hajnoczi
2020-03-10 11:04 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-10 11:04 ` Stefan Hajnoczi
2020-03-10 18:19 ` Vivek Goyal
2020-03-10 18:19 ` [Virtio-fs] " Vivek Goyal
2020-03-10 18:19 ` Vivek Goyal
2020-03-11 17:34 ` Stefan Hajnoczi
2020-03-11 17:34 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-11 17:34 ` Stefan Hajnoczi
2020-03-11 19:29 ` Vivek Goyal
2020-03-11 19:29 ` [Virtio-fs] " Vivek Goyal
2020-03-11 19:29 ` Vivek Goyal
2020-03-10 11:12 ` Michael S. Tsirkin
2020-03-10 11:12 ` [Virtio-fs] " Michael S. Tsirkin
2020-03-10 11:12 ` Michael S. Tsirkin
2020-03-10 18:47 ` Vivek Goyal
2020-03-10 18:47 ` [Virtio-fs] " Vivek Goyal
2020-03-10 18:47 ` Vivek Goyal
2020-03-10 21:27 ` Michael S. Tsirkin
2020-03-10 21:27 ` [Virtio-fs] " Michael S. Tsirkin
2020-03-10 21:27 ` Michael S. Tsirkin
2020-03-04 16:58 ` [PATCH 05/20] virtio: Implement get_shm_region for MMIO transport Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 11:06 ` Stefan Hajnoczi
2020-03-10 11:06 ` [Virtio-fs] " Stefan Hajnoczi
2020-03-10 11:06 ` Stefan Hajnoczi
2020-03-04 16:58 ` [PATCH 06/20] virtiofs: Provide a helper function for virtqueue initialization Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 14:10 ` Miklos Szeredi
2020-03-10 14:10 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 14:10 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 07/20] fuse: Get rid of no_mount_options Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 14:12 ` Miklos Szeredi
2020-03-10 14:12 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 14:12 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 08/20] fuse,virtiofs: Add a mount option to enable dax Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 08/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 08/20] fuse,virtiofs: " Vivek Goyal
2020-03-10 14:16 ` Miklos Szeredi
2020-03-10 14:16 ` [Virtio-fs] [PATCH 08/20] fuse, virtiofs: " Miklos Szeredi
2020-03-10 14:16 ` [PATCH 08/20] fuse,virtiofs: " Miklos Szeredi
2020-03-04 16:58 ` [PATCH 09/20] virtio_fs, dax: Set up virtio_fs dax_device Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 10/20] fuse,virtiofs: Keep a list of free dax memory ranges Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 10/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 10/20] fuse,virtiofs: " Vivek Goyal
2020-03-10 19:29 ` Miklos Szeredi
2020-03-10 19:29 ` [Virtio-fs] [PATCH 10/20] fuse, virtiofs: " Miklos Szeredi
2020-03-10 19:29 ` [PATCH 10/20] fuse,virtiofs: " Miklos Szeredi
2020-03-04 16:58 ` [PATCH 11/20] fuse: implement FUSE_INIT map_alignment field Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 19:31 ` Miklos Szeredi
2020-03-10 19:31 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 19:31 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 12/20] fuse: Introduce setupmapping/removemapping commands Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-10 19:49 ` Miklos Szeredi
2020-03-10 19:49 ` [Virtio-fs] " Miklos Szeredi
2020-03-10 19:49 ` Miklos Szeredi
2020-03-10 20:33 ` Vivek Goyal
2020-03-10 20:33 ` [Virtio-fs] " Vivek Goyal
2020-03-10 20:33 ` Vivek Goyal
2020-03-11 7:03 ` Amir Goldstein
2020-03-11 7:03 ` [Virtio-fs] " Amir Goldstein
2020-03-11 7:03 ` Amir Goldstein
2020-03-11 14:19 ` Miklos Szeredi
2020-03-11 14:19 ` [Virtio-fs] " Miklos Szeredi
2020-03-11 14:19 ` Miklos Szeredi
2020-03-11 14:41 ` Vivek Goyal
2020-03-11 14:41 ` [Virtio-fs] " Vivek Goyal
2020-03-11 14:41 ` Vivek Goyal
2020-03-11 15:12 ` Miklos Szeredi
2020-03-11 15:12 ` [Virtio-fs] " Miklos Szeredi
2020-03-11 15:12 ` Miklos Szeredi
2020-03-04 16:58 ` [PATCH 13/20] fuse, dax: Implement dax read/write operations Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-12 9:43 ` Miklos Szeredi
2020-03-12 9:43 ` [Virtio-fs] " Miklos Szeredi
2020-03-12 9:43 ` Miklos Szeredi
2020-03-12 16:02 ` Vivek Goyal
2020-03-12 16:02 ` [Virtio-fs] " Vivek Goyal
2020-03-12 16:02 ` Vivek Goyal
2020-03-13 10:18 ` Miklos Szeredi
2020-03-13 10:18 ` [Virtio-fs] " Miklos Szeredi
2020-03-13 10:18 ` Miklos Szeredi
2020-03-13 13:41 ` Vivek Goyal
2020-03-13 13:41 ` [Virtio-fs] " Vivek Goyal
2020-03-13 13:41 ` Vivek Goyal
2020-04-04 0:25 ` Liu Bo
2020-04-04 0:25 ` [Virtio-fs] " Liu Bo
2020-04-04 0:25 ` Liu Bo
2020-04-14 12:54 ` Vivek Goyal
2020-04-14 12:54 ` [Virtio-fs] " Vivek Goyal
2020-04-14 12:54 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 14/20] fuse,dax: add DAX mmap support Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 15/20] fuse, dax: Take ->i_mmap_sem lock during dax page fault Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 16/20] fuse,virtiofs: Define dax address space operations Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 16/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 16/20] fuse,virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 17/20] fuse,virtiofs: Maintain a list of busy elements Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 17/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 17/20] fuse,virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 18/20] fuse: Release file in process context Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 19/20] fuse: Take inode lock for dax inode truncation Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] " Vivek Goyal
2020-03-04 16:58 ` Vivek Goyal
2020-03-04 16:58 ` [PATCH 20/20] fuse,virtiofs: Add logic to free up a memory range Vivek Goyal
2020-03-04 16:58 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-03-04 16:58 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-03-11 5:16 ` Liu Bo
2020-03-11 5:16 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-11 5:16 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-11 12:59 ` Vivek Goyal
2020-03-11 12:59 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-03-11 12:59 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-03-11 17:24 ` Liu Bo
2020-03-11 17:24 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-11 17:24 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-26 0:09 ` Liu Bo
2020-03-26 0:09 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-26 0:09 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-27 14:01 ` Vivek Goyal
2020-03-27 14:01 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-03-27 14:01 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-03-27 22:06 ` Liu Bo
2020-03-27 22:06 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-03-27 22:06 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-04-14 19:30 ` Vivek Goyal
2020-04-14 19:30 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-04-14 19:30 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-04-15 17:22 ` Liu Bo
2020-04-15 17:22 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-04-15 17:22 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-04-16 19:05 ` Vivek Goyal
2020-04-16 19:05 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Vivek Goyal
2020-04-16 19:05 ` [PATCH 20/20] fuse,virtiofs: " Vivek Goyal
2020-04-17 18:05 ` Liu Bo
2020-04-17 18:05 ` [Virtio-fs] [PATCH 20/20] fuse, virtiofs: " Liu Bo
2020-04-17 18:05 ` [PATCH 20/20] fuse,virtiofs: " Liu Bo
2020-03-11 5:22 ` [PATCH 00/20] virtiofs: Add DAX support Amir Goldstein
2020-03-11 5:22 ` [Virtio-fs] " Amir Goldstein
2020-03-11 5:22 ` Amir Goldstein
2020-03-11 13:09 ` Vivek Goyal
2020-03-11 13:09 ` [Virtio-fs] " Vivek Goyal
2020-03-11 13:09 ` Vivek Goyal
2020-03-11 18:48 ` Vivek Goyal
2020-03-11 18:48 ` [Virtio-fs] " Vivek Goyal
2020-03-11 18:48 ` Vivek Goyal
2020-03-11 19:32 ` Amir Goldstein
2020-03-11 19:32 ` [Virtio-fs] " Amir Goldstein
2020-03-11 19:32 ` Amir Goldstein
2020-03-11 19:39 ` Vivek Goyal
2020-03-11 19:39 ` [Virtio-fs] " Vivek Goyal
2020-03-11 19:39 ` Vivek Goyal
2020-03-11 13:38 ` Patrick Ohly
2020-03-11 13:38 ` [Virtio-fs] " Patrick Ohly
2020-03-11 13:38 ` Patrick Ohly
2020-03-16 13:02 ` Vivek Goyal
2020-03-16 13:02 ` [Virtio-fs] " Vivek Goyal
2020-03-16 13:02 ` Vivek Goyal
2020-03-17 8:28 ` Patrick Ohly
2020-03-17 8:28 ` [Virtio-fs] " Patrick Ohly
2020-03-17 8:28 ` Patrick Ohly
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