2019-01-31 03:07:45

by Souptick Joarder

Subject: [PATCHv2 3/9] drivers/firewire/core-iso.c: Convert to use vm_insert_range_buggy

Convert to use vm_insert_range_buggy to map range of kernel memory
to user vma.

This driver has ignored vm_pgoff and mapped the entire pages. We
could later "fix" these drivers to behave according to the normal
vm_pgoff offsetting simply by removing the _buggy suffix on the
function name and if that causes regressions, it gives us an easy
way to revert.

Signed-off-by: Souptick Joarder <[email protected]>
---
drivers/firewire/core-iso.c | 15 ++-------------
1 file changed, 2 insertions(+), 13 deletions(-)

diff --git a/drivers/firewire/core-iso.c b/drivers/firewire/core-iso.c
index 35e784c..99a6582 100644
--- a/drivers/firewire/core-iso.c
+++ b/drivers/firewire/core-iso.c
@@ -107,19 +107,8 @@ int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
int fw_iso_buffer_map_vma(struct fw_iso_buffer *buffer,
struct vm_area_struct *vma)
{
- unsigned long uaddr;
- int i, err;
-
- uaddr = vma->vm_start;
- for (i = 0; i < buffer->page_count; i++) {
- err = vm_insert_page(vma, uaddr, buffer->pages[i]);
- if (err)
- return err;
-
- uaddr += PAGE_SIZE;
- }
-
- return 0;
+ return vm_insert_range_buggy(vma, buffer->pages,
+ buffer->page_count);
}

void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer,
--
1.9.1

2019-02-03 12:12:39

by Souptick Joarder

Subject: Re: [PATCHv2 3/9] drivers/firewire/core-iso.c: Convert to use vm_insert_range_buggy

Hi Stefanr,

On Thu, Jan 31, 2019 at 8:35 AM Souptick Joarder <[email protected]> wrote:
>
> Convert to use vm_insert_range_buggy to map range of kernel memory
> to user vma.
>
> This driver has ignored vm_pgoff and mapped the entire pages. We
> could later "fix" these drivers to behave according to the normal
> vm_pgoff offsetting simply by removing the _buggy suffix on the
> function name and if that causes regressions, it gives us an easy
> way to revert.
>
> Signed-off-by: Souptick Joarder <[email protected]>

Can you please help to review this patch ?

> ---
> drivers/firewire/core-iso.c | 15 ++-------------
> 1 file changed, 2 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/firewire/core-iso.c b/drivers/firewire/core-iso.c
> index 35e784c..99a6582 100644
> --- a/drivers/firewire/core-iso.c
> +++ b/drivers/firewire/core-iso.c
> @@ -107,19 +107,8 @@ int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
> int fw_iso_buffer_map_vma(struct fw_iso_buffer *buffer,
> struct vm_area_struct *vma)
> {
> - unsigned long uaddr;
> - int i, err;
> -
> - uaddr = vma->vm_start;
> - for (i = 0; i < buffer->page_count; i++) {
> - err = vm_insert_page(vma, uaddr, buffer->pages[i]);
> - if (err)
> - return err;
> -
> - uaddr += PAGE_SIZE;
> - }
> -
> - return 0;
> + return vm_insert_range_buggy(vma, buffer->pages,
> + buffer->page_count);
> }
>
> void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer,
> --
> 1.9.1
>