mm: replace get_user_pages() write/force parameters with gup_flags

This removes the 'write' and 'force' from get_user_pages() and replaces
them with 'gup_flags' 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 <[email protected]>
Acked-by: Christian König <[email protected]>
Acked-by: Jesper Nilsson <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Lorenzo Stoakes 2016-10-13 01:20:16 +01:00 • committed by Linus Torvalds
commit 768ae309a9
22 changed files with 49 additions and 54 deletions

View file

@ -94,6 +94,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
unsigned long dma_attrs = 0;
struct scatterlist *sg, *sg_list_start;
int need_release = 0;
unsigned int gup_flags = FOLL_WRITE;
if (dmasync)
dma_attrs |= DMA_ATTR_WRITE_BARRIER;
@ -183,6 +184,9 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
if (ret)
goto out;
if (!umem->writable)
gup_flags |= FOLL_FORCE;
need_release = 1;
sg_list_start = umem->sg_head.sgl;
@ -190,7 +194,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr,
ret = get_user_pages(cur_base,
min_t(unsigned long, npages,
PAGE_SIZE / sizeof (struct page *)),
1, !umem->writable, page_list, vma_list);
gup_flags, page_list, vma_list);
if (ret < 0)
goto out;

View file

@ -472,7 +472,7 @@ int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
goto out;
}
ret = get_user_pages(uaddr & PAGE_MASK, 1, 1, 0, pages, NULL);
ret = get_user_pages(uaddr & PAGE_MASK, 1, FOLL_WRITE, pages, NULL);
if (ret < 0)
goto out;

View file

@ -67,7 +67,8 @@ static int __qib_get_user_pages(unsigned long start_page, size_t num_pages,
for (got = 0; got < num_pages; got += ret) {
ret = get_user_pages(start_page + got * PAGE_SIZE,
num_pages - got, 1, 1,
num_pages - got,
FOLL_WRITE | FOLL_FORCE,
p + got, NULL);
if (ret < 0)
goto bail_release;

View file

@ -111,6 +111,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
int i;
int flags;
dma_addr_t pa;
unsigned int gup_flags;
if (!can_do_mlock())
return -EPERM;
@ -135,6 +136,8 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
flags = IOMMU_READ | IOMMU_CACHE;
flags |= (writable) ? IOMMU_WRITE : 0;
gup_flags = FOLL_WRITE;
gup_flags |= (writable) ? 0 : FOLL_FORCE;
cur_base = addr & PAGE_MASK;
ret = 0;
@ -142,7 +145,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
ret = get_user_pages(cur_base,
min_t(unsigned long, npages,
PAGE_SIZE / sizeof(struct page *)),
1, !writable, page_list, NULL);
gup_flags, page_list, NULL);
if (ret < 0)
goto out;