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 lstoakes@gmail.com --- 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,
/* Get user pages for DMA Xfer */ y_pages = get_user_pages_unlocked(y_dma.uaddr, - y_dma.page_count, 0, 1, &dma->map[0]); + y_dma.page_count, &dma->map[0], FOLL_FORCE); uv_pages = 0; /* silence gcc. value is set and consumed only if: */ if (y_pages == y_dma.page_count) { uv_pages = get_user_pages_unlocked(uv_dma.uaddr, - uv_dma.page_count, 0, 1, &dma->map[y_pages]); + uv_dma.page_count, &dma->map[y_pages], + FOLL_FORCE); }
if (y_pages != y_dma.page_count || uv_pages != uv_dma.page_count) { diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c index 7af5226..618422e 100644 --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -4922,9 +4922,8 @@ static int sgl_map_user_pages(struct st_buffer *STbp, res = get_user_pages_unlocked( uaddr, nr_pages, - rw == READ, - 0, /* don't force */ - pages); + pages, + rw == READ ? FOLL_WRITE : 0); /* don't force */
/* Errors and no page mapped should return here */ if (res < nr_pages) diff --git a/drivers/video/fbdev/pvr2fb.c b/drivers/video/fbdev/pvr2fb.c index 3b1ca44..a2564ab 100644 --- a/drivers/video/fbdev/pvr2fb.c +++ b/drivers/video/fbdev/pvr2fb.c @@ -686,8 +686,8 @@ static ssize_t pvr2fb_write(struct fb_info *info, const char *buf, if (!pages) return -ENOMEM;
- ret = get_user_pages_unlocked((unsigned long)buf, nr_pages, WRITE, - 0, pages); + ret = get_user_pages_unlocked((unsigned long)buf, nr_pages, pages, + FOLL_WRITE);
if (ret < nr_pages) { nr_pages = ret; diff --git a/include/linux/mm.h b/include/linux/mm.h index 2db98b6..6adc4bc 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1287,7 +1287,7 @@ long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages); + struct page **pages, unsigned int gup_flags); int get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages);
diff --git a/mm/gup.c b/mm/gup.c index 3d620dd..cfcb014 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -897,17 +897,10 @@ EXPORT_SYMBOL(__get_user_pages_unlocked); * "force" parameter). */ long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages) + struct page **pages, unsigned int gup_flags) { - unsigned int flags = FOLL_TOUCH; - - if (write) - flags |= FOLL_WRITE; - if (force) - flags |= FOLL_FORCE; - return __get_user_pages_unlocked(current, current->mm, start, nr_pages, - pages, flags); + pages, gup_flags | FOLL_TOUCH); } EXPORT_SYMBOL(get_user_pages_unlocked);
@@ -1525,7 +1518,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write, 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) { diff --git a/mm/nommu.c b/mm/nommu.c index 925dcc1..7e27add 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -197,17 +197,10 @@ long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, EXPORT_SYMBOL(__get_user_pages_unlocked);
long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages) + struct page **pages, unsigned int gup_flags) { - unsigned int flags = 0; - - if (write) - flags |= FOLL_WRITE; - if (force) - flags |= FOLL_FORCE; - return __get_user_pages_unlocked(current, current->mm, start, nr_pages, - pages, flags); + pages, gup_flags); } EXPORT_SYMBOL(get_user_pages_unlocked);
diff --git a/mm/util.c b/mm/util.c index 662cddf..4c685bd 100644 --- a/mm/util.c +++ b/mm/util.c @@ -283,7 +283,8 @@ EXPORT_SYMBOL_GPL(__get_user_pages_fast); int __weak get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) { - return get_user_pages_unlocked(start, nr_pages, write, 0, pages); + return get_user_pages_unlocked(start, nr_pages, pages, + write ? FOLL_WRITE : 0); } EXPORT_SYMBOL_GPL(get_user_pages_fast);
diff --git a/net/ceph/pagevec.c b/net/ceph/pagevec.c index 00d2601..1a7c9a7 100644 --- a/net/ceph/pagevec.c +++ b/net/ceph/pagevec.c @@ -26,7 +26,7 @@ struct page **ceph_get_direct_page_vector(const void __user *data, while (got < num_pages) { rc = get_user_pages_unlocked( (unsigned long)data + ((unsigned long)got * PAGE_SIZE), - num_pages - got, write_page, 0, pages + got); + num_pages - got, pages + got, write_page ? FOLL_WRITE : 0); if (rc < 0) break; BUG_ON(rc == 0);