The quilt patch titled
Subject: mm: allow per-VMA locks on file-backed VMAs
has been removed from the -mm tree. Its filename was
mm-allow-per-vma-locks-on-file-backed-vmas.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: allow per-VMA locks on file-backed VMAs
Date: Mon, 24 Jul 2023 19:54:02 +0100
Remove the TCP layering violation by allowing per-VMA locks on all VMAs.
The fault path will immediately fail in handle_mm_fault(). There may be a
small performance reduction from this patch as a little unnecessary work
will be done on each page fault. See later patches for the improvement.
Link: https://lkml.kernel.org/r/20230724185410.1124082-3-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Arjun Roy <arjunroy@xxxxxxxxxx>
Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Punit Agrawal <punit.agrawal@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
MAINTAINERS | 1 -
include/linux/net_mm.h | 17 -----------------
include/net/tcp.h | 1 -
mm/memory.c | 10 +++++-----
net/ipv4/tcp.c | 11 ++++-------
5 files changed, 9 insertions(+), 31 deletions(-)
--- a/include/linux/net_mm.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifdef CONFIG_MMU
-
-#ifdef CONFIG_INET
-extern const struct vm_operations_struct tcp_vm_ops;
-static inline bool vma_is_tcp(const struct vm_area_struct *vma)
-{
- return vma->vm_ops == &tcp_vm_ops;
-}
-#else
-static inline bool vma_is_tcp(const struct vm_area_struct *vma)
-{
- return false;
-}
-#endif /* CONFIG_INET*/
-
-#endif /* CONFIG_MMU */
--- a/include/net/tcp.h~mm-allow-per-vma-locks-on-file-backed-vmas
+++ a/include/net/tcp.h
@@ -45,7 +45,6 @@
#include <linux/memcontrol.h>
#include <linux/bpf-cgroup.h>
#include <linux/siphash.h>
-#include <linux/net_mm.h>
extern struct inet_hashinfo tcp_hashinfo;
--- a/MAINTAINERS~mm-allow-per-vma-locks-on-file-backed-vmas
+++ a/MAINTAINERS
@@ -14829,7 +14829,6 @@ NETWORKING [TCP]
M: Eric Dumazet <edumazet@xxxxxxxxxx>
L: netdev@xxxxxxxxxxxxxxx
S: Maintained
-F: include/linux/net_mm.h
F: include/linux/tcp.h
F: include/net/tcp.h
F: include/trace/events/tcp.h
--- a/mm/memory.c~mm-allow-per-vma-locks-on-file-backed-vmas
+++ a/mm/memory.c
@@ -77,7 +77,6 @@
#include <linux/ptrace.h>
#include <linux/vmalloc.h>
#include <linux/sched/sysctl.h>
-#include <linux/net_mm.h>
#include <trace/events/kmem.h>
@@ -5223,6 +5222,11 @@ vm_fault_t handle_mm_fault(struct vm_are
goto out;
}
+ if ((flags & FAULT_FLAG_VMA_LOCK) && !vma_is_anonymous(vma)) {
+ vma_end_read(vma);
+ return VM_FAULT_RETRY;
+ }
+
/*
* Enable the memcg OOM handling for faults triggered in user
* space. Kernel faults are handled more gracefully.
@@ -5394,10 +5398,6 @@ retry:
if (!vma)
goto inval;
- /* Only anonymous and tcp vmas are supported for now */
- if (!vma_is_anonymous(vma) && !vma_is_tcp(vma))
- goto inval;
-
if (!vma_start_read(vma))
goto inval;
--- a/net/ipv4/tcp.c~mm-allow-per-vma-locks-on-file-backed-vmas
+++ a/net/ipv4/tcp.c
@@ -1739,7 +1739,7 @@ void tcp_update_recv_tstamps(struct sk_b
}
#ifdef CONFIG_MMU
-const struct vm_operations_struct tcp_vm_ops = {
+static const struct vm_operations_struct tcp_vm_ops = {
};
int tcp_mmap(struct file *file, struct socket *sock,
@@ -2042,13 +2042,10 @@ static struct vm_area_struct *find_tcp_v
unsigned long address,
bool *mmap_locked)
{
- struct vm_area_struct *vma = NULL;
+ struct vm_area_struct *vma = lock_vma_under_rcu(mm, address);
-#ifdef CONFIG_PER_VMA_LOCK
- vma = lock_vma_under_rcu(mm, address);
-#endif
if (vma) {
- if (!vma_is_tcp(vma)) {
+ if (vma->vm_ops != &tcp_vm_ops) {
vma_end_read(vma);
return NULL;
}
@@ -2058,7 +2055,7 @@ static struct vm_area_struct *find_tcp_v
mmap_read_lock(mm);
vma = vma_lookup(mm, address);
- if (!vma || !vma_is_tcp(vma)) {
+ if (!vma || vma->vm_ops != &tcp_vm_ops) {
mmap_read_unlock(mm);
return NULL;
}
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-drop-per-vma-lock-when-returning-vm_fault_retry-or-vm_fault_completed-fix.patch
zswap-make-zswap_store-take-a-folio.patch
memcg-convert-get_obj_cgroup_from_page-to-get_obj_cgroup_from_folio.patch
swap-remove-some-calls-to-compound_head-in-swap_readpage.patch
zswap-make-zswap_load-take-a-folio.patch
mm-improve-the-comment-in-isolate_migratepages_block.patch
minmax-add-in_range-macro.patch
mm-convert-page_table_check_pte_set-to-page_table_check_ptes_set.patch
mm-add-generic-flush_icache_pages-and-documentation.patch
mm-add-folio_flush_mapping.patch
mm-remove-arch_implements_flush_dcache_folio.patch
mm-add-default-definition-of-set_ptes.patch
alpha-implement-the-new-page-table-range-api.patch
arc-implement-the-new-page-table-range-api.patch
arm-implement-the-new-page-table-range-api.patch
arm64-implement-the-new-page-table-range-api.patch
csky-implement-the-new-page-table-range-api.patch
hexagon-implement-the-new-page-table-range-api.patch
ia64-implement-the-new-page-table-range-api.patch
ia64-implement-the-new-page-table-range-api-fix.patch
loongarch-implement-the-new-page-table-range-api.patch
m68k-implement-the-new-page-table-range-api.patch
microblaze-implement-the-new-page-table-range-api.patch
mips-implement-the-new-page-table-range-api.patch
nios2-implement-the-new-page-table-range-api.patch
openrisc-implement-the-new-page-table-range-api.patch
parisc-implement-the-new-page-table-range-api.patch
powerpc-implement-the-new-page-table-range-api.patch
powerpc-implement-the-new-page-table-range-api-fix.patch
riscv-implement-the-new-page-table-range-api.patch
s390-implement-the-new-page-table-range-api.patch
sh-implement-the-new-page-table-range-api.patch
sparc32-implement-the-new-page-table-range-api.patch
sparc64-implement-the-new-page-table-range-api.patch
um-implement-the-new-page-table-range-api.patch
x86-implement-the-new-page-table-range-api.patch
xtensa-implement-the-new-page-table-range-api.patch
mm-remove-page_mapping_file.patch
mm-rationalise-flush_icache_pages-and-flush_icache_page.patch
mm-tidy-up-set_ptes-definition.patch
mm-use-flush_icache_pages-in-do_set_pmd.patch
mm-call-update_mmu_cache_range-in-more-page-fault-handling-paths.patch
