similar to: [patch 2/2] xen-gntdev: unlock on error path in gntdev_mmap()

On 10/28/19 4:10 PM, Jason Gunthorpe wrote: > From: Jason Gunthorpe <jgg at mellanox.com> > > gntdev simply wants to monitor a specific VMA for any notifier events, > this can be done straightforwardly using mmu_range_notifier_insert() over > the VMA's VA range. > > The notifier should be attached until the original VMA is destroyed. > > It is unclear if any of

From: Jason Gunthorpe <jgg at mellanox.com> gntdev simply wants to monitor a specific VMA for any notifier events, this can be done straightforwardly using mmu_range_notifier_insert() over the VMA's VA range. The notifier should be attached until the original VMA is destroyed. It is unclear if any of this is even sane, but at least a lot of duplicate code is removed. Cc: Oleksandr

copy_to_user() returns the amount of data remaining to be copied. We want to return a negative error code here. The upper layers just call WARN_ON() if we return non-zero so this doesn't change the behavior. But returning -EFAULT is still cleaner. Signed-off-by: Dan Carpenter <error27 at gmail.com> diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 017ce60..b0f9e8f

copy_to_user() returns the amount of data remaining to be copied. We want to return a negative error code here. The upper layers just call WARN_ON() if we return non-zero so this doesn't change the behavior. But returning -EFAULT is still cleaner. Signed-off-by: Dan Carpenter <error27 at gmail.com> diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 017ce60..b0f9e8f

copy_to_user() returns the amount of data remaining to be copied. We want to return a negative error code here. The upper layers just call WARN_ON() if we return non-zero so this doesn't change the behavior. But returning -EFAULT is still cleaner. Signed-off-by: Dan Carpenter <error27 at gmail.com> diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 017ce60..b0f9e8f

This flag controls the meaning of gnttab_map_grant_ref.host_addr and specifies that the field contains a refernce to the pte entry to be used to perform the mapping. Therefore move the use of this flag to the point at which we actually use a reference to the pte instead of something else, splitting up the usage of the flag in this way is confusing and potentially error prone. The other flags are

Since when we are using the m2p_override it is not true anymore that the mmap''ed area doesn''t have corresponsing struct pages. Removing the VM_PFNMAP flag makes get_user_pages work on the mmap''ed user vma. An example test case would be using a Xen userspace block backend (QDISK) on a file on NFS using O_DIRECT. The patch should be backported back to 2.6.38.

The only time when granted pages need to be treated specially is when using Xen''s PTE modification for grant mappings owned by another domain. Otherwise, the area does not require VM_DONTCOPY and VM_PFNMAP, since it can be accessed just like any other page of RAM. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> --- drivers/xen/gntalloc.c | 14 ++++++++++++--

Since we are using the m2p_override we do have struct pages corresponding to the user vma mmap''ed by gntdev. Removing the VM_PFNMAP flag makes get_user_pages work on that vma. An example test case would be using a Xen userspace block backend (QDISK) on a file on NFS using O_DIRECT. The patch should be backported back to 2.6.38. Signed-off-by: Stefano Stabellini

On 11/4/19 9:31 PM, Jason Gunthorpe wrote: > On Mon, Nov 04, 2019 at 05:03:31PM -0500, Boris Ostrovsky wrote: >> On 10/28/19 4:10 PM, Jason Gunthorpe wrote: >>> @@ -445,17 +438,9 @@ static void gntdev_vma_close(struct vm_area_struct *vma) >>> struct gntdev_priv *priv = file->private_data; >>> >>> pr_debug("gntdev_vma_close %p\n",

On 10/28/19 4:10 PM, Jason Gunthorpe wrote: > @@ -445,17 +438,9 @@ static void gntdev_vma_close(struct vm_area_struct *vma) > struct gntdev_priv *priv = file->private_data; > > pr_debug("gntdev_vma_close %p\n", vma); > - if (use_ptemod) { > - /* It is possible that an mmu notifier could be running > - * concurrently, so take priv->lock to ensure that

On Wed, Oct 30, 2019 at 12:55:37PM -0400, Boris Ostrovsky wrote: > On 10/28/19 4:10 PM, Jason Gunthorpe wrote: > > From: Jason Gunthorpe <jgg at mellanox.com> > > > > gntdev simply wants to monitor a specific VMA for any notifier events, > > this can be done straightforwardly using mmu_range_notifier_insert() over > > the VMA's VA range. > > >

On Tue, Nov 05, 2019 at 10:16:46AM -0500, Boris Ostrovsky wrote: > > So, I suppose it can be relaxed to a null test and a WARN_ON that it > > hasn't changed? > > You mean > > if (use_ptemod) { > ??????? WARN_ON(map->vma != vma); > ??????? ... > > > Yes, that sounds good. I amended my copy of the patch with the above, has this rework shown signs

On Mon, Nov 04, 2019 at 05:03:31PM -0500, Boris Ostrovsky wrote: > On 10/28/19 4:10 PM, Jason Gunthorpe wrote: > > @@ -445,17 +438,9 @@ static void gntdev_vma_close(struct vm_area_struct *vma) > > struct gntdev_priv *priv = file->private_data; > > > > pr_debug("gntdev_vma_close %p\n", vma); > > - if (use_ptemod) { > > - /* It is possible

On 11/7/19 3:36 PM, Jason Gunthorpe wrote: > On Tue, Nov 05, 2019 at 10:16:46AM -0500, Boris Ostrovsky wrote: > >>> So, I suppose it can be relaxed to a null test and a WARN_ON that it >>> hasn't changed? >> You mean >> >> if (use_ptemod) { >> ??????? WARN_ON(map->vma != vma); >> ??????? ... >> >> >> Yes, that sounds

From: Jason Gunthorpe <jgg at mellanox.com> 8 of the mmu_notifier using drivers (i915_gem, radeon_mn, umem_odp, hfi1, scif_dma, vhost, gntdev, hmm) drivers are using a common pattern where they only use invalidate_range_start/end and immediately check the invalidating range against some driver data structure to tell if the driver is interested. Half of them use an interval_tree, the others

As usual, written and tested on 2.6.24-rc4 and made apply to the 2.6.18 tree without further testing. Signed-off-by: Jan Beulich <jbeulich@novell.com> Index: head-2007-12-11/drivers/xen/Kconfig =================================================================== --- head-2007-12-11.orig/drivers/xen/Kconfig 2007-10-18 16:15:28.000000000 +0200 +++ head-2007-12-11/drivers/xen/Kconfig

Hi, Looks like this patch broke automated builds due to a lack of a matching line in the defconfigs. Below is a patch that makes this a module for xen and xen0, unconfigured for xenU. That might not be the best thing here however. Thanks kurt Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com> ===================================================== diff -r cd744c5ec950

On 11/1/19 1:48 PM, Jason Gunthorpe wrote: > On Wed, Oct 30, 2019 at 12:55:37PM -0400, Boris Ostrovsky wrote: >> On 10/28/19 4:10 PM, Jason Gunthorpe wrote: >>> From: Jason Gunthorpe <jgg at mellanox.com> >>> >>> gntdev simply wants to monitor a specific VMA for any notifier events, >>> this can be done straightforwardly using

On Mon, Oct 28, 2019 at 05:10:25PM -0300, Jason Gunthorpe wrote: > From: Jason Gunthorpe <jgg at mellanox.com> > > DMA_SHARED_BUFFER can not be enabled by the user (it represents a library > set in the kernel). The kconfig convention is to use select for such > symbols so they are turned on implicitly when the user enables a kconfig > that needs them. > > Otherwise