[PATCH mm-unstable v1 12/20] RDMA/siw: remove FOLL_FORCE usage
From: David Hildenbrand <hidden>
Date: 2022-11-16 10:39:29
Also in:
dri-devel, linux-alpha, linux-fsdevel, linux-kselftest, linux-media, linux-mips, linux-mm, linux-perf-users, linux-rdma, linux-samsung-soc, linux-security-module, linux-um, linuxppc-dev, lkml, sparclinux
Subsystem:
infiniband subsystem, soft-iwarp driver (siw), the rest · Maintainers:
Jason Gunthorpe, Leon Romanovsky, Bernard Metzler, Linus Torvalds
GUP now supports reliable R/O long-term pinning in COW mappings, such that we break COW early. MAP_SHARED VMAs only use the shared zeropage so far in one corner case (DAXFS file with holes), which can be ignored because GUP does not support long-term pinning in fsdax (see check_vma_flags()). Consequently, FOLL_FORCE | FOLL_WRITE | FOLL_LONGTERM is no longer required for reliable R/O long-term pinning: FOLL_LONGTERM is sufficient. So stop using FOLL_FORCE, which is really only for ptrace access. Cc: Bernard Metzler <redacted> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Leon Romanovsky <leon@kernel.org> Signed-off-by: David Hildenbrand <redacted> --- drivers/infiniband/sw/siw/siw_mem.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c
index 61c17db70d65..b2b33dd3b4fa 100644
--- a/drivers/infiniband/sw/siw/siw_mem.c
+++ b/drivers/infiniband/sw/siw/siw_mem.c@@ -368,7 +368,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable) struct mm_struct *mm_s; u64 first_page_va; unsigned long mlock_limit; - unsigned int foll_flags = FOLL_WRITE; + unsigned int foll_flags = FOLL_LONGTERM; int num_pages, num_chunks, i, rv = 0; if (!can_do_mlock())
@@ -391,8 +391,8 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable) mmgrab(mm_s); - if (!writable) - foll_flags |= FOLL_FORCE; + if (writable) + foll_flags |= FOLL_WRITE; mmap_read_lock(mm_s);
@@ -423,8 +423,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable) while (nents) { struct page **plist = &umem->page_chunk[i].plist[got]; - rv = pin_user_pages(first_page_va, nents, - foll_flags | FOLL_LONGTERM, + rv = pin_user_pages(first_page_va, nents, foll_flags, plist, NULL); if (rv < 0) goto out_sem_up;
--
2.38.1
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