| Message ID | 20230628065919.54042-3-lulu@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | reconnect support in vduse | expand |
On Wed, Jun 28, 2023 at 2:59 PM Cindy Lu <lulu@redhat.com> wrote: > > From: Your Name <you@example.com> > > Add the operation for mmap, The user space APP will > use this function to map the pages to userspace Please be specific in the log. E.g why and what the main goal for this mmap. > > Signed-off-by: Cindy Lu <lulu@redhat.com> > --- > drivers/vdpa/vdpa_user/vduse_dev.c | 49 ++++++++++++++++++++++++++++++ > 1 file changed, 49 insertions(+) > > diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c > index f845dc46b1db..1b833bf0ae37 100644 > --- a/drivers/vdpa/vdpa_user/vduse_dev.c > +++ b/drivers/vdpa/vdpa_user/vduse_dev.c > @@ -1313,6 +1313,54 @@ static struct vduse_dev *vduse_dev_get_from_minor(int minor) > return dev; > } > > + > +static vm_fault_t vduse_vm_fault(struct vm_fault *vmf) > +{ > + struct vduse_dev *dev = vmf->vma->vm_file->private_data; > + struct vm_area_struct *vma = vmf->vma; > + u16 index = vma->vm_pgoff; > + > + struct vdpa_reconnect_info *info; > + info = &dev->reconnect_info[index]; > + > + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, PFN_DOWN(info->addr), > + PAGE_SIZE, vma->vm_page_prot)) I'm not sure if this can work e.g do we want to use separate pages for each virtqueue (I think the answer is yes). > + return VM_FAULT_SIGBUS; > + return VM_FAULT_NOPAGE; > +} > + > +static const struct vm_operations_struct vduse_vm_ops = { > + .fault = vduse_vm_fault, > +}; > + > +static int vduse_mmap(struct file *file, struct vm_area_struct *vma) > +{ > + struct vduse_dev *dev = file->private_data; > + struct vdpa_reconnect_info *info; > + unsigned long index = vma->vm_pgoff; > + > + if (vma->vm_end - vma->vm_start != PAGE_SIZE) > + return -EINVAL; > + if ((vma->vm_flags & VM_SHARED) == 0) > + return -EINVAL; > + > + if (index > 65535) > + return -EINVAL; > + > + info = &dev->reconnect_info[index]; > + if (info->addr & (PAGE_SIZE - 1)) > + return -EINVAL; > + if (vma->vm_end - vma->vm_start != info->size) { > + return -ENOTSUPP; > + } How can userspace know the correct size (info->size) here? > + > + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); Why do you need VM_IO, VM_PFNMAP and VM_DONTDUMP here? Thanks > + vma->vm_ops = &vduse_vm_ops; > + > + return 0; > +} > + > static int vduse_dev_open(struct inode *inode, struct file *file) > { > int ret; > @@ -1345,6 +1393,7 @@ static const struct file_operations vduse_dev_fops = { > .unlocked_ioctl = vduse_dev_ioctl, > .compat_ioctl = compat_ptr_ioctl, > .llseek = noop_llseek, > + .mmap = vduse_mmap, > }; > > static struct vduse_dev *vduse_dev_create(void) > -- > 2.34.3 >
On Wed, Jun 28, 2023 at 4:08 PM Jason Wang <jasowang@redhat.com> wrote: > > On Wed, Jun 28, 2023 at 2:59 PM Cindy Lu <lulu@redhat.com> wrote: > > > > From: Your Name <you@example.com> > > > > Add the operation for mmap, The user space APP will > > use this function to map the pages to userspace > > Please be specific in the log. E.g why and what the main goal for this mmap. > > > > > Signed-off-by: Cindy Lu <lulu@redhat.com> > > --- > > drivers/vdpa/vdpa_user/vduse_dev.c | 49 ++++++++++++++++++++++++++++++ > > 1 file changed, 49 insertions(+) > > > > diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c > > index f845dc46b1db..1b833bf0ae37 100644 > > --- a/drivers/vdpa/vdpa_user/vduse_dev.c > > +++ b/drivers/vdpa/vdpa_user/vduse_dev.c > > @@ -1313,6 +1313,54 @@ static struct vduse_dev *vduse_dev_get_from_minor(int minor) > > return dev; > > } > > > > + > > +static vm_fault_t vduse_vm_fault(struct vm_fault *vmf) > > +{ > > + struct vduse_dev *dev = vmf->vma->vm_file->private_data; > > + struct vm_area_struct *vma = vmf->vma; > > + u16 index = vma->vm_pgoff; > > + > > + struct vdpa_reconnect_info *info; > > + info = &dev->reconnect_info[index]; > > + > > + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > > + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, PFN_DOWN(info->addr), > > + PAGE_SIZE, vma->vm_page_prot)) > > I'm not sure if this can work e.g do we want to use separate pages for > each virtqueue (I think the answer is yes). > yes, this map the separate pages per vq, beads on my test this works > > + return VM_FAULT_SIGBUS; > > + return VM_FAULT_NOPAGE; > > +} > > + > > +static const struct vm_operations_struct vduse_vm_ops = { > > + .fault = vduse_vm_fault, > > +}; > > + > > +static int vduse_mmap(struct file *file, struct vm_area_struct *vma) > > +{ > > + struct vduse_dev *dev = file->private_data; > > + struct vdpa_reconnect_info *info; > > + unsigned long index = vma->vm_pgoff; > > + > > + if (vma->vm_end - vma->vm_start != PAGE_SIZE) > > + return -EINVAL; > > + if ((vma->vm_flags & VM_SHARED) == 0) > > + return -EINVAL; > > + > > + if (index > 65535) > > + return -EINVAL; > > + > > + info = &dev->reconnect_info[index]; > > + if (info->addr & (PAGE_SIZE - 1)) > > + return -EINVAL; > > + if (vma->vm_end - vma->vm_start != info->size) { > > + return -ENOTSUPP; > > + } > > How can userspace know the correct size (info->size) here? > I had hard code the size in userpace , I will add the new ioctl of get the map size Thanks cindy > > + > > + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); > > Why do you need VM_IO, VM_PFNMAP and VM_DONTDUMP here? > > Thanks > > > + vma->vm_ops = &vduse_vm_ops; > > + > > + return 0; > > +} > > + > > static int vduse_dev_open(struct inode *inode, struct file *file) > > { > > int ret; > > @@ -1345,6 +1393,7 @@ static const struct file_operations vduse_dev_fops = { > > .unlocked_ioctl = vduse_dev_ioctl, > > .compat_ioctl = compat_ptr_ioctl, > > .llseek = noop_llseek, > > + .mmap = vduse_mmap, > > }; > > > > static struct vduse_dev *vduse_dev_create(void) > > -- > > 2.34.3 > > >
On 6/28/23 08:59, Cindy Lu wrote: > From: Your Name <you@example.com> > > Add the operation for mmap, The user space APP will > use this function to map the pages to userspace > > Signed-off-by: Cindy Lu <lulu@redhat.com> > --- > drivers/vdpa/vdpa_user/vduse_dev.c | 49 ++++++++++++++++++++++++++++++ > 1 file changed, 49 insertions(+) > > diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c > index f845dc46b1db..1b833bf0ae37 100644 > --- a/drivers/vdpa/vdpa_user/vduse_dev.c > +++ b/drivers/vdpa/vdpa_user/vduse_dev.c > @@ -1313,6 +1313,54 @@ static struct vduse_dev *vduse_dev_get_from_minor(int minor) > return dev; > } > > + > +static vm_fault_t vduse_vm_fault(struct vm_fault *vmf) > +{ > + struct vduse_dev *dev = vmf->vma->vm_file->private_data; > + struct vm_area_struct *vma = vmf->vma; > + u16 index = vma->vm_pgoff; > + > + struct vdpa_reconnect_info *info; > + info = &dev->reconnect_info[index]; > + > + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, PFN_DOWN(info->addr), > + PAGE_SIZE, vma->vm_page_prot)) > + return VM_FAULT_SIGBUS; > + return VM_FAULT_NOPAGE; > +} > + > +static const struct vm_operations_struct vduse_vm_ops = { > + .fault = vduse_vm_fault, > +}; > + > +static int vduse_mmap(struct file *file, struct vm_area_struct *vma) > +{ > + struct vduse_dev *dev = file->private_data; > + struct vdpa_reconnect_info *info; > + unsigned long index = vma->vm_pgoff; > + > + if (vma->vm_end - vma->vm_start != PAGE_SIZE) > + return -EINVAL; > + if ((vma->vm_flags & VM_SHARED) == 0) > + return -EINVAL; > + > + if (index > 65535) > + return -EINVAL; You declare an array of 64 entries in patch 1, so it can overflow. > + > + info = &dev->reconnect_info[index]; > + if (info->addr & (PAGE_SIZE - 1)) > + return -EINVAL; > + if (vma->vm_end - vma->vm_start != info->size) { > + return -ENOTSUPP; > + } > + > + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); > + vma->vm_ops = &vduse_vm_ops; > + > + return 0; > +} > + > static int vduse_dev_open(struct inode *inode, struct file *file) > { > int ret; > @@ -1345,6 +1393,7 @@ static const struct file_operations vduse_dev_fops = { > .unlocked_ioctl = vduse_dev_ioctl, > .compat_ioctl = compat_ptr_ioctl, > .llseek = noop_llseek, > + .mmap = vduse_mmap, > }; > > static struct vduse_dev *vduse_dev_create(void)
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index f845dc46b1db..1b833bf0ae37 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1313,6 +1313,54 @@ static struct vduse_dev *vduse_dev_get_from_minor(int minor) return dev; } + +static vm_fault_t vduse_vm_fault(struct vm_fault *vmf) +{ + struct vduse_dev *dev = vmf->vma->vm_file->private_data; + struct vm_area_struct *vma = vmf->vma; + u16 index = vma->vm_pgoff; + + struct vdpa_reconnect_info *info; + info = &dev->reconnect_info[index]; + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + if (remap_pfn_range(vma, vmf->address & PAGE_MASK, PFN_DOWN(info->addr), + PAGE_SIZE, vma->vm_page_prot)) + return VM_FAULT_SIGBUS; + return VM_FAULT_NOPAGE; +} + +static const struct vm_operations_struct vduse_vm_ops = { + .fault = vduse_vm_fault, +}; + +static int vduse_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct vduse_dev *dev = file->private_data; + struct vdpa_reconnect_info *info; + unsigned long index = vma->vm_pgoff; + + if (vma->vm_end - vma->vm_start != PAGE_SIZE) + return -EINVAL; + if ((vma->vm_flags & VM_SHARED) == 0) + return -EINVAL; + + if (index > 65535) + return -EINVAL; + + info = &dev->reconnect_info[index]; + if (info->addr & (PAGE_SIZE - 1)) + return -EINVAL; + if (vma->vm_end - vma->vm_start != info->size) { + return -ENOTSUPP; + } + + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); + vma->vm_ops = &vduse_vm_ops; + + return 0; +} + static int vduse_dev_open(struct inode *inode, struct file *file) { int ret; @@ -1345,6 +1393,7 @@ static const struct file_operations vduse_dev_fops = { .unlocked_ioctl = vduse_dev_ioctl, .compat_ioctl = compat_ptr_ioctl, .llseek = noop_llseek, + .mmap = vduse_mmap, }; static struct vduse_dev *vduse_dev_create(void)