Re: [PATCH 03/10] mm: replace get_user_pages_unlocked() write/force parameters with gup_flags

2016-10-18 Thread Jan Kara
On Thu 13-10-16 01:20:13, Lorenzo Stoakes wrote:
> This patch removes the write and force parameters from 
> get_user_pages_unlocked()
> and replaces them with a gup_flags parameter to make the use of FOLL_FORCE
> explicit in callers as use of this flag can result in surprising behaviour 
> (and
> hence bugs) within the mm subsystem.
> 
> Signed-off-by: Lorenzo Stoakes 

Looks good. You can add:

Reviewed-by: Jan Kara 

Honza
-- 
Jan Kara 
SUSE Labs, CR


Re: [PATCH 03/10] mm: replace get_user_pages_unlocked() write/force parameters with gup_flags

2016-10-18 Thread Jan Kara
On Thu 13-10-16 01:20:13, Lorenzo Stoakes wrote:
> This patch removes the write and force parameters from 
> get_user_pages_unlocked()
> and replaces them with a gup_flags parameter to make the use of FOLL_FORCE
> explicit in callers as use of this flag can result in surprising behaviour 
> (and
> hence bugs) within the mm subsystem.
> 
> Signed-off-by: Lorenzo Stoakes 

Looks good. You can add:

Reviewed-by: Jan Kara 

Honza
-- 
Jan Kara 
SUSE Labs, CR


[PATCH 03/10] mm: replace get_user_pages_unlocked() write/force parameters with gup_flags

2016-10-12 Thread Lorenzo Stoakes
This patch removes the write and force parameters from get_user_pages_unlocked()
and replaces them with a gup_flags parameter to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.

Signed-off-by: Lorenzo Stoakes 
---
 arch/mips/mm/gup.c |  2 +-
 arch/s390/mm/gup.c |  3 ++-
 arch/sh/mm/gup.c   |  3 ++-
 arch/sparc/mm/gup.c|  3 ++-
 arch/x86/mm/gup.c  |  2 +-
 drivers/media/pci/ivtv/ivtv-udma.c |  4 ++--
 drivers/media/pci/ivtv/ivtv-yuv.c  |  5 +++--
 drivers/scsi/st.c  |  5 ++---
 drivers/video/fbdev/pvr2fb.c   |  4 ++--
 include/linux/mm.h |  2 +-
 mm/gup.c   | 14 --
 mm/nommu.c | 11 ++-
 mm/util.c  |  3 ++-
 net/ceph/pagevec.c |  2 +-
 14 files changed, 27 insertions(+), 36 deletions(-)

diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c
index 42d124f..d8c3c15 100644
--- a/arch/mips/mm/gup.c
+++ b/arch/mips/mm/gup.c
@@ -287,7 +287,7 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
pages += nr;
 
ret = get_user_pages_unlocked(start, (end - start) >> PAGE_SHIFT,
- write, 0, pages);
+ pages, write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index adb0c34..18d4107 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -266,7 +266,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
/* Try to get the remaining pages with get_user_pages */
start += nr << PAGE_SHIFT;
pages += nr;
-   ret = get_user_pages_unlocked(start, nr_pages - nr, write, 0, pages);
+   ret = get_user_pages_unlocked(start, nr_pages - nr, pages,
+ write ? FOLL_WRITE : 0);
/* Have to be a bit careful with return values */
if (nr > 0)
ret = (ret < 0) ? nr : ret + nr;
diff --git a/arch/sh/mm/gup.c b/arch/sh/mm/gup.c
index 40fa6c8..063c298 100644
--- a/arch/sh/mm/gup.c
+++ b/arch/sh/mm/gup.c
@@ -258,7 +258,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
pages += nr;
 
ret = get_user_pages_unlocked(start,
-   (end - start) >> PAGE_SHIFT, write, 0, pages);
+   (end - start) >> PAGE_SHIFT, pages,
+   write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
index 4e06750..cd0e32b 100644
--- a/arch/sparc/mm/gup.c
+++ b/arch/sparc/mm/gup.c
@@ -238,7 +238,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
pages += nr;
 
ret = get_user_pages_unlocked(start,
-   (end - start) >> PAGE_SHIFT, write, 0, pages);
+   (end - start) >> PAGE_SHIFT, pages,
+   write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c
index b8b6a60..0d4fb3e 100644
--- a/arch/x86/mm/gup.c
+++ b/arch/x86/mm/gup.c
@@ -435,7 +435,7 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
 
ret = get_user_pages_unlocked(start,
  (end - start) >> PAGE_SHIFT,
- write, 0, pages);
+ pages, write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/drivers/media/pci/ivtv/ivtv-udma.c 
b/drivers/media/pci/ivtv/ivtv-udma.c
index 4769469..2c9232e 100644
--- a/drivers/media/pci/ivtv/ivtv-udma.c
+++ b/drivers/media/pci/ivtv/ivtv-udma.c
@@ -124,8 +124,8 @@ int ivtv_udma_setup(struct ivtv *itv, unsigned long 
ivtv_dest_addr,
}
 
/* Get user pages for DMA Xfer */
-   err = get_user_pages_unlocked(user_dma.uaddr, user_dma.page_count, 0,
-   1, dma->map);
+   err = get_user_pages_unlocked(user_dma.uaddr, user_dma.page_count,
+   dma->map, FOLL_FORCE);
 
if (user_dma.page_count != err) {
IVTV_DEBUG_WARN("failed to map user pages, returned %d instead 
of %d\n",
diff --git a/drivers/media/pci/ivtv/ivtv-yuv.c 
b/drivers/media/pci/ivtv/ivtv-yuv.c
index b094054..f7299d3 100644
--- a/drivers/media/pci/ivtv/ivtv-yuv.c
+++ b/drivers/media/pci/ivtv/ivtv-yuv.c
@@ -76,11 +76,12 @@ static int ivtv_yuv_prep_user_dma(struct ivtv *itv, struct 

[PATCH 03/10] mm: replace get_user_pages_unlocked() write/force parameters with gup_flags

2016-10-12 Thread Lorenzo Stoakes
This patch removes the write and force parameters from get_user_pages_unlocked()
and replaces them with a gup_flags parameter to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.

Signed-off-by: Lorenzo Stoakes 
---
 arch/mips/mm/gup.c |  2 +-
 arch/s390/mm/gup.c |  3 ++-
 arch/sh/mm/gup.c   |  3 ++-
 arch/sparc/mm/gup.c|  3 ++-
 arch/x86/mm/gup.c  |  2 +-
 drivers/media/pci/ivtv/ivtv-udma.c |  4 ++--
 drivers/media/pci/ivtv/ivtv-yuv.c  |  5 +++--
 drivers/scsi/st.c  |  5 ++---
 drivers/video/fbdev/pvr2fb.c   |  4 ++--
 include/linux/mm.h |  2 +-
 mm/gup.c   | 14 --
 mm/nommu.c | 11 ++-
 mm/util.c  |  3 ++-
 net/ceph/pagevec.c |  2 +-
 14 files changed, 27 insertions(+), 36 deletions(-)

diff --git a/arch/mips/mm/gup.c b/arch/mips/mm/gup.c
index 42d124f..d8c3c15 100644
--- a/arch/mips/mm/gup.c
+++ b/arch/mips/mm/gup.c
@@ -287,7 +287,7 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
pages += nr;
 
ret = get_user_pages_unlocked(start, (end - start) >> PAGE_SHIFT,
- write, 0, pages);
+ pages, write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index adb0c34..18d4107 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -266,7 +266,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
/* Try to get the remaining pages with get_user_pages */
start += nr << PAGE_SHIFT;
pages += nr;
-   ret = get_user_pages_unlocked(start, nr_pages - nr, write, 0, pages);
+   ret = get_user_pages_unlocked(start, nr_pages - nr, pages,
+ write ? FOLL_WRITE : 0);
/* Have to be a bit careful with return values */
if (nr > 0)
ret = (ret < 0) ? nr : ret + nr;
diff --git a/arch/sh/mm/gup.c b/arch/sh/mm/gup.c
index 40fa6c8..063c298 100644
--- a/arch/sh/mm/gup.c
+++ b/arch/sh/mm/gup.c
@@ -258,7 +258,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
pages += nr;
 
ret = get_user_pages_unlocked(start,
-   (end - start) >> PAGE_SHIFT, write, 0, pages);
+   (end - start) >> PAGE_SHIFT, pages,
+   write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/sparc/mm/gup.c b/arch/sparc/mm/gup.c
index 4e06750..cd0e32b 100644
--- a/arch/sparc/mm/gup.c
+++ b/arch/sparc/mm/gup.c
@@ -238,7 +238,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
pages += nr;
 
ret = get_user_pages_unlocked(start,
-   (end - start) >> PAGE_SHIFT, write, 0, pages);
+   (end - start) >> PAGE_SHIFT, pages,
+   write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c
index b8b6a60..0d4fb3e 100644
--- a/arch/x86/mm/gup.c
+++ b/arch/x86/mm/gup.c
@@ -435,7 +435,7 @@ int get_user_pages_fast(unsigned long start, int nr_pages, 
int write,
 
ret = get_user_pages_unlocked(start,
  (end - start) >> PAGE_SHIFT,
- write, 0, pages);
+ pages, write ? FOLL_WRITE : 0);
 
/* Have to be a bit careful with return values */
if (nr > 0) {
diff --git a/drivers/media/pci/ivtv/ivtv-udma.c 
b/drivers/media/pci/ivtv/ivtv-udma.c
index 4769469..2c9232e 100644
--- a/drivers/media/pci/ivtv/ivtv-udma.c
+++ b/drivers/media/pci/ivtv/ivtv-udma.c
@@ -124,8 +124,8 @@ int ivtv_udma_setup(struct ivtv *itv, unsigned long 
ivtv_dest_addr,
}
 
/* Get user pages for DMA Xfer */
-   err = get_user_pages_unlocked(user_dma.uaddr, user_dma.page_count, 0,
-   1, dma->map);
+   err = get_user_pages_unlocked(user_dma.uaddr, user_dma.page_count,
+   dma->map, FOLL_FORCE);
 
if (user_dma.page_count != err) {
IVTV_DEBUG_WARN("failed to map user pages, returned %d instead 
of %d\n",
diff --git a/drivers/media/pci/ivtv/ivtv-yuv.c 
b/drivers/media/pci/ivtv/ivtv-yuv.c
index b094054..f7299d3 100644
--- a/drivers/media/pci/ivtv/ivtv-yuv.c
+++ b/drivers/media/pci/ivtv/ivtv-yuv.c
@@ -76,11 +76,12 @@ static int ivtv_yuv_prep_user_dma(struct ivtv *itv, struct 
ivtv_user_dma *dma,