* [PATCH v2 12/33] MAINTAINERS: Move mm/interval_tree.c to rmap section
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
This file implements code for the interval trees used by the file and anon
rmap implementation, so belongs in the rmap section.
Acked-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
MAINTAINERS | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/MAINTAINERS b/MAINTAINERS
index c3e535ca4bef..ef168b583325 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17208,6 +17208,7 @@ R: Lance Yang <lance.yang@linux.dev>
L: linux-mm@kvack.org
S: Maintained
F: include/linux/rmap.h
+F: mm/interval_tree.c
F: mm/page_vma_mapped.c
F: mm/rmap.c
F: tools/testing/selftests/mm/rmap.c
@@ -17313,7 +17314,6 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
F: include/trace/events/mmap.h
F: fs/proc/task_mmu.c
F: fs/proc/task_nommu.c
-F: mm/interval_tree.c
F: mm/mincore.c
F: mm/mlock.c
F: mm/mmap.c
--
2.55.0
^ permalink raw reply related
* [PATCH v2 13/33] mm/vma: introduce and use vmg_pages(), vmg_[start, end]_pgoff()
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
In the VMA logic we often need to determine the number of pages in the
specified merge range, as well as the start and end page offsets of that
range.
Introduce and use helpers for these purposes.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 11 ++++-------
mm/vma.h | 17 +++++++++++++++++
2 files changed, 21 insertions(+), 7 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index 35ba3475128f..995de8198fbb 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -197,11 +197,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
*/
static bool can_vma_merge_before(struct vma_merge_struct *vmg)
{
- pgoff_t pglen = PHYS_PFN(vmg->end - vmg->start);
-
if (is_mergeable_vma(vmg, /* merge_next = */ true) &&
is_mergeable_anon_vma(vmg, /* merge_next = */ true)) {
- if (vmg->next->vm_pgoff == vmg->pgoff + pglen)
+ if (vmg_end_pgoff(vmg) == vma_start_pgoff(vmg->next))
return true;
}
@@ -221,7 +219,7 @@ static bool can_vma_merge_after(struct vma_merge_struct *vmg)
{
if (is_mergeable_vma(vmg, /* merge_next = */ false) &&
is_mergeable_anon_vma(vmg, /* merge_next = */ false)) {
- if (vmg->prev->vm_pgoff + vma_pages(vmg->prev) == vmg->pgoff)
+ if (vma_end_pgoff(vmg->prev) == vmg_start_pgoff(vmg))
return true;
}
return false;
@@ -759,7 +757,7 @@ static int commit_merge(struct vma_merge_struct *vmg)
*/
vma_adjust_trans_huge(vma, vmg->start, vmg->end,
vmg->__adjust_middle_start ? vmg->middle : NULL);
- vma_set_range(vma, vmg->start, vmg->end, vmg->pgoff);
+ vma_set_range(vma, vmg->start, vmg->end, vmg_start_pgoff(vmg));
vmg_adjust_set_range(vmg);
vma_iter_store_overwrite(vmg->vmi, vmg->target);
@@ -962,8 +960,7 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
* middle next
* shrink/delete extend
*/
-
- pgoff_t pglen = PHYS_PFN(vmg->end - vmg->start);
+ const pgoff_t pglen = vmg_pages(vmg);
VM_WARN_ON_VMG(!merge_right, vmg);
/* If we are offset into a VMA, then prev must be middle. */
diff --git a/mm/vma.h b/mm/vma.h
index 8e4b61a7304c..527716c8739d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -230,6 +230,23 @@ static inline bool vmg_nomem(struct vma_merge_struct *vmg)
return vmg->state == VMA_MERGE_ERROR_NOMEM;
}
+static inline pgoff_t vmg_start_pgoff(const struct vma_merge_struct *vmg)
+{
+ return vmg->pgoff;
+}
+
+static inline pgoff_t vmg_pages(const struct vma_merge_struct *vmg)
+{
+ const unsigned long size = vmg->end - vmg->start;
+
+ return size >> PAGE_SHIFT;
+}
+
+static inline pgoff_t vmg_end_pgoff(const struct vma_merge_struct *vmg)
+{
+ return vmg_start_pgoff(vmg) + vmg_pages(vmg);
+}
+
/* Assumes addr >= vma->vm_start. */
static inline pgoff_t vma_pgoff_offset(struct vm_area_struct *vma,
unsigned long addr)
--
2.55.0
^ permalink raw reply related
* [PATCH v2 14/33] mm/vma: clean up anon_vma_compatible()
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Break up the existing very large conditional, add comments and use
vma_[start/end]_pgoff() to make clearer what we're doing here.
No functional change intended.
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index 995de8198fbb..084afdf37385 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -1967,14 +1967,25 @@ static int anon_vma_compatible(struct vm_area_struct *a, struct vm_area_struct *
{
vma_flags_t diff = vma_flags_diff_pair(&a->flags, &b->flags);
+ /* Ignore flags that mprotect() can change. */
vma_flags_clear_mask(&diff, VMA_ACCESS_FLAGS);
+ /* Ignore flags that do not impact merging. */
vma_flags_clear_mask(&diff, VMA_IGNORE_MERGE_FLAGS);
- return a->vm_end == b->vm_start &&
- mpol_equal(vma_policy(a), vma_policy(b)) &&
- a->vm_file == b->vm_file &&
- vma_flags_empty(&diff) &&
- b->vm_pgoff == a->vm_pgoff + ((b->vm_start - a->vm_start) >> PAGE_SHIFT);
+ /* Must be adjacent. */
+ if (a->vm_end != b->vm_start)
+ return false;
+ /* Must have matching policy. */
+ if (!mpol_equal(vma_policy(a), vma_policy(b)))
+ return false;
+ /* Must both be anon or map the same file (MAP_PRIVATE case). */
+ if (a->vm_file != b->vm_file)
+ return false;
+ /* Flags must be equivalent modulo mprotect(). */
+ if (!vma_flags_empty(&diff))
+ return false;
+ /* Page offset must align. */
+ return vma_end_pgoff(a) == vma_start_pgoff(b);
}
/*
--
2.55.0
^ permalink raw reply related
* [PATCH v2 15/33] mm/vma: refactor vmg_adjust_set_range() for clarity
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Add comments with ASCII diagrams to describe what we're doing, avoid
dubious use of PHYS_PFN(), and use vma_start_pgoff().
The most complicated scenario represented here is vmg->__adjust_next_start
- when this is set, vmg->[start, end] actually indicate the range to be
retained, so take special care to describe this accurately.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 47 insertions(+), 4 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index 084afdf37385..7265a054cfa3 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -704,11 +704,54 @@ static void vmg_adjust_set_range(struct vma_merge_struct *vmg)
pgoff_t pgoff;
if (vmg->__adjust_middle_start) {
- adjust = vmg->middle;
- pgoff = adjust->vm_pgoff + PHYS_PFN(vmg->end - adjust->vm_start);
+ /*
+ * vmg->start vmg->end
+ * | |
+ * v merge v
+ * <------------->
+ * delta
+ * <------>
+ * |------|----------------|
+ * | prev | middle |
+ * |------|----------------|
+ * ^
+ * |
+ * middle->vm_start
+ */
+ struct vm_area_struct *middle = vmg->middle;
+ const unsigned long delta = vmg->end - middle->vm_start;
+
+ pgoff = vma_start_pgoff(middle) + (delta >> PAGE_SHIFT);
+ adjust = middle;
} else if (vmg->__adjust_next_start) {
- adjust = vmg->next;
- pgoff = adjust->vm_pgoff - PHYS_PFN(adjust->vm_start - vmg->end);
+ /*
+ * Originally:
+ *
+ * vmg->start vmg->end
+ * | |
+ * v merge v
+ * <------------>
+ * . .
+ * merge_existing_range() updates to:
+ * . .
+ * vmg->start vmg->end .
+ * | | .
+ * v retain v .
+ * <----------> .
+ * delta .
+ * <-----> .
+ * |----------------|------|
+ * | middle | next |
+ * |----------------|------|
+ * ^
+ * |
+ * next->vm_start
+ */
+ struct vm_area_struct *next = vmg->next;
+ const unsigned long delta = next->vm_start - vmg->end;
+
+ pgoff = vma_start_pgoff(next) - (delta >> PAGE_SHIFT);
+ adjust = next;
} else {
return;
}
--
2.55.0
^ permalink raw reply related
* [PATCH v2 16/33] mm/vma: minor cleanup of expand_[upwards, downwards]()
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Adjust the stack expansion functions expand_upwards() and
expand_downwards() such that they are expressed in terms of named constant
values, and make use of vma_start_pgoff().
This clearly documents that we are referencing the page offset of the start
of the VMA.
Additionally this cleans up the overflow check in expand_upwards().
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 17 +++++++----------
1 file changed, 7 insertions(+), 10 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index 7265a054cfa3..5d5e60ea8a25 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -3216,13 +3216,12 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
/* Somebody else might have raced and expanded it already */
if (address > vma->vm_end) {
- unsigned long size, grow;
-
- size = address - vma->vm_start;
- grow = (address - vma->vm_end) >> PAGE_SHIFT;
+ const unsigned long size = address - vma->vm_start;
+ const unsigned long grow = (address - vma->vm_end) >> PAGE_SHIFT;
+ const pgoff_t pgoff = vma_start_pgoff(vma);
error = -ENOMEM;
- if (vma->vm_pgoff + (size >> PAGE_SHIFT) >= vma->vm_pgoff) {
+ if (pgoff + (size >> PAGE_SHIFT) >= pgoff) {
error = acct_stack_growth(vma, size, grow);
if (!error) {
if (vma_test(vma, VMA_LOCKED_BIT))
@@ -3295,13 +3294,11 @@ int expand_downwards(struct vm_area_struct *vma, unsigned long address)
/* Somebody else might have raced and expanded it already */
if (address < vma->vm_start) {
- unsigned long size, grow;
-
- size = vma->vm_end - address;
- grow = (vma->vm_start - address) >> PAGE_SHIFT;
+ const unsigned long size = vma->vm_end - address;
+ const unsigned long grow = (vma->vm_start - address) >> PAGE_SHIFT;
error = -ENOMEM;
- if (grow <= vma->vm_pgoff) {
+ if (grow <= vma_start_pgoff(vma)) {
error = acct_stack_growth(vma, size, grow);
if (!error) {
if (vma_test(vma, VMA_LOCKED_BIT))
--
2.55.0
^ permalink raw reply related
* [PATCH v2 17/33] mm: introduce and use linear_page_delta()
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King, Ackerley Tng
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
It's often useful to obtain the number of pages a given address lies at
within a VMA.
Add linear_page_delta() to determine this and update linear_page_index() to
make use of it.
Add comments to describe both linear_page_delta() and linear_page_index().
We refer the reader to the comment for vma_start_pgoff() so we don't
duplicate information about the meaning of a VMA's page offset, which is
also less likely to result in bitrot.
No functional change intended.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
include/linux/pagemap.h | 33 +++++++++++++++++++++++++++++++--
1 file changed, 31 insertions(+), 2 deletions(-)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 2c3718d592d6..a950070b045f 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -1063,11 +1063,40 @@ static inline pgoff_t folio_pgoff(const struct folio *folio)
return folio->index;
}
+/**
+ * linear_page_delta() - Determine the relative page offset of @address within
+ * @vma.
+ * @vma: The VMA in which @address resides.
+ * @address: The address whose relative page offset is required.
+ *
+ * The result is identical for both file-backed and anonymous mappings and
+ * simply determines how many pages @address lies from @vma->vm_start.
+ *
+ * Returns: The number of pages @address is offset by within @vma.
+ */
+static inline pgoff_t linear_page_delta(const struct vm_area_struct *vma,
+ const unsigned long address)
+{
+ return (address - vma->vm_start) >> PAGE_SHIFT;
+}
+
+/**
+ * linear_page_index() - Determine the absolute page offset of @address within
+ * @vma.
+ * @vma: The VMA in which @address resides.
+ * @address: The address whose absolute page offset is required.
+ *
+ * See the comment for vma_start_pgoff() for a description of what the page
+ * offset signifies.
+ *
+ * Returns: The absolute page offset of @address within @vma.
+ */
static inline pgoff_t linear_page_index(const struct vm_area_struct *vma,
const unsigned long address)
{
pgoff_t pgoff;
- pgoff = (address - vma->vm_start) >> PAGE_SHIFT;
+
+ pgoff = linear_page_delta(vma, address);
pgoff += vma->vm_pgoff;
return pgoff;
}
@@ -1219,7 +1248,7 @@ static inline vm_fault_t folio_lock_or_retry(struct folio *folio,
void folio_wait_bit(struct folio *folio, int bit_nr);
int folio_wait_bit_killable(struct folio *folio, int bit_nr);
-/*
+/*
* Wait for a folio to be unlocked.
*
* This must be called with the caller "holding" the folio,
--
2.55.0
^ permalink raw reply related
* [PATCH v2 18/33] mm/vma: use vma_start_pgoff(), linear_page_index() in mm code
From: Lorenzo Stoakes @ 2026-07-10 20:16 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
There are many instances in which linear_page_index() (as well as
linear_page_delta()) is open-coded, which is confusing and inconsistent.
Additionally, vma->vm_pgoff doesn't necessarily make it clear that this is
the page offset of the start of the VMA range.
Doing so also aids greppability.
So use vma_start_pgoff() in favour of directly accessing vma->vm_pgoff, and
linear_page_index() where we can.
This also lays the ground for future changes which will add an anonymous
page offset in order to be able to index MAP_PRIVATE-file backed anon
folios in terms of their virtual page offset.
No functional change intended.
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: SJ Park <sj@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
include/linux/huge_mm.h | 1 +
include/linux/hugetlb.h | 3 +--
include/linux/pagemap.h | 2 +-
mm/damon/vaddr.c | 5 +++--
mm/debug.c | 2 +-
mm/filemap.c | 7 ++++---
mm/huge_memory.c | 2 +-
mm/hugetlb.c | 11 ++++-------
mm/internal.h | 24 ++++++++++++++----------
mm/khugepaged.c | 3 ++-
mm/madvise.c | 6 +++---
mm/mapping_dirty_helpers.c | 2 +-
mm/memory.c | 25 +++++++++++++------------
mm/mempolicy.c | 13 +++++++------
mm/mremap.c | 12 ++++--------
mm/msync.c | 4 ++--
mm/nommu.c | 7 ++++---
mm/pagewalk.c | 2 +-
mm/shmem.c | 9 +++++----
mm/userfaultfd.c | 4 ++--
mm/util.c | 4 ++--
mm/vma.c | 15 +++++++--------
mm/vma_exec.c | 4 ++--
mm/vma_init.c | 2 +-
24 files changed, 86 insertions(+), 83 deletions(-)
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 19a7bfce279e..cae97c307280 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -230,6 +230,7 @@ static inline bool thp_vma_suitable_order(struct vm_area_struct *vma,
/* Don't have to check pgoff for anonymous vma */
if (!vma_is_anonymous(vma)) {
+ /* vma_start_pgoff() in mm.h so not available. */
if (!IS_ALIGNED((vma->vm_start >> PAGE_SHIFT) - vma->vm_pgoff,
hpage_size >> PAGE_SHIFT))
return false;
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 4115076e4922..32901236ab0f 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -801,8 +801,7 @@ static inline pgoff_t hugetlb_linear_page_index(struct vm_area_struct *vma,
{
struct hstate *h = hstate_vma(vma);
- return ((address - vma->vm_start) >> huge_page_shift(h)) +
- (vma->vm_pgoff >> huge_page_order(h));
+ return linear_page_index(vma, address) >> huge_page_order(h);
}
static inline bool order_is_gigantic(unsigned int order)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index a950070b045f..c6fc783aaee5 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -1097,7 +1097,7 @@ static inline pgoff_t linear_page_index(const struct vm_area_struct *vma,
pgoff_t pgoff;
pgoff = linear_page_delta(vma, address);
- pgoff += vma->vm_pgoff;
+ pgoff += vma_start_pgoff(vma);
return pgoff;
}
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 2058db9c01d5..d10b8042adb5 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -10,6 +10,7 @@
#include <linux/mman.h>
#include <linux/mmu_notifier.h>
#include <linux/page_idle.h>
+#include <linux/pagemap.h>
#include <linux/pagewalk.h>
#include <linux/sched/mm.h>
@@ -623,8 +624,8 @@ static void damos_va_migrate_dests_add(struct folio *folio,
}
order = folio_order(folio);
- ilx = vma->vm_pgoff >> order;
- ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order);
+ ilx = vma_start_pgoff(vma) >> order;
+ ilx += linear_page_delta(vma, addr) >> order;
for (i = 0; i < dests->nr_dests; i++)
weight_total += dests->weight_arr[i];
diff --git a/mm/debug.c b/mm/debug.c
index 77fa8fe1d641..497654b36f1a 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -163,7 +163,7 @@ void dump_vma(const struct vm_area_struct *vma)
"flags: %#lx(%pGv)\n",
vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
(unsigned long)pgprot_val(vma->vm_page_prot),
- vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
+ vma->anon_vma, vma->vm_ops, vma_start_pgoff(vma),
vma->vm_file, vma->vm_private_data,
#ifdef CONFIG_PER_VMA_LOCK
refcount_read(&vma->vm_refcnt),
diff --git a/mm/filemap.c b/mm/filemap.c
index b39111abdc4b..1dbb4c6f824e 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3411,8 +3411,8 @@ static struct file *do_sync_mmap_readahead(struct vm_fault *vmf)
* of memory.
*/
struct vm_area_struct *vma = vmf->vma;
- unsigned long start = vma->vm_pgoff;
- unsigned long end = start + vma_pages(vma);
+ const unsigned long start = vma_start_pgoff(vma);
+ const unsigned long end = vma_end_pgoff(vma);
unsigned long ra_end;
ra->order = exec_folio_order();
@@ -3930,7 +3930,8 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
goto out;
}
- addr = vma->vm_start + ((start_pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ addr = vma->vm_start +
+ ((start_pgoff - vma_start_pgoff(vma)) << PAGE_SHIFT);
vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, addr, &vmf->ptl);
if (!vmf->pte) {
folio_unlock(folio);
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 25612af72dca..790d2720b9e3 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -180,7 +180,7 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma,
*/
if (!in_pf && shmem_file(vma->vm_file))
return orders & shmem_allowable_huge_orders(file_inode(vma->vm_file),
- vma, vma->vm_pgoff, 0,
+ vma, vma_start_pgoff(vma), 0,
forced_collapse);
if (!vma_is_anonymous(vma)) {
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 92796c0cd89e..30f257a2bfee 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1011,8 +1011,7 @@ static long region_count(struct resv_map *resv, long f, long t)
static pgoff_t vma_hugecache_offset(struct hstate *h,
struct vm_area_struct *vma, unsigned long address)
{
- return ((address - vma->vm_start) >> huge_page_shift(h)) +
- (vma->vm_pgoff >> huge_page_order(h));
+ return linear_page_index(vma, address) >> huge_page_order(h);
}
/*
@@ -5444,8 +5443,7 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
* from page cache lookup which is in HPAGE_SIZE units.
*/
address = address & huge_page_mask(h);
- pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
+ pgoff = linear_page_index(vma, address);
mapping = vma->vm_file->f_mapping;
/*
@@ -6904,7 +6902,7 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma,
struct vm_area_struct *vma,
unsigned long addr, pgoff_t idx)
{
- unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) +
+ unsigned long saddr = ((idx - vma_start_pgoff(svma)) << PAGE_SHIFT) +
svma->vm_start;
unsigned long sbase = saddr & PUD_MASK;
unsigned long s_end = sbase + PUD_SIZE;
@@ -6989,8 +6987,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pud_t *pud)
{
struct address_space *mapping = vma->vm_file->f_mapping;
- pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff;
+ const pgoff_t idx = linear_page_index(vma, addr);
struct vm_area_struct *svma;
unsigned long saddr;
pte_t *spte = NULL;
diff --git a/mm/internal.h b/mm/internal.h
index 3d30650a8440..01a762bcc2b2 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1004,26 +1004,28 @@ static inline bool
folio_within_range(struct folio *folio, struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
- pgoff_t pgoff, addr;
- unsigned long vma_pglen = vma_pages(vma);
+ const unsigned long vma_pglen = vma_pages(vma);
+ pgoff_t pgoff_folio, pgoff_vma_start;
+ unsigned long addr;
VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio);
if (start > end)
return false;
+ pgoff_folio = folio_pgoff(folio);
+ pgoff_vma_start = vma_start_pgoff(vma);
+
if (start < vma->vm_start)
start = vma->vm_start;
if (end > vma->vm_end)
end = vma->vm_end;
- pgoff = folio_pgoff(folio);
-
/* if folio start address is not in vma range */
- if (!in_range(pgoff, vma->vm_pgoff, vma_pglen))
+ if (!in_range(pgoff_folio, pgoff_vma_start, vma_pglen))
return false;
- addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ addr = vma->vm_start + ((pgoff_folio - pgoff_vma_start) << PAGE_SHIFT);
return !(addr < start || end - addr < folio_size(folio));
}
@@ -1095,15 +1097,16 @@ extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);
static inline unsigned long vma_address(const struct vm_area_struct *vma,
pgoff_t pgoff, unsigned long nr_pages)
{
+ const pgoff_t pgoff_start = vma_start_pgoff(vma);
unsigned long address;
- if (pgoff >= vma->vm_pgoff) {
+ if (pgoff >= pgoff_start) {
address = vma->vm_start +
- ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ ((pgoff - pgoff_start) << PAGE_SHIFT);
/* Check for address beyond vma (or wrapped through 0?) */
if (address < vma->vm_start || address >= vma->vm_end)
address = -EFAULT;
- } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) {
+ } else if (pgoff + nr_pages - 1 >= pgoff_start) {
/* Test above avoids possibility of wrap to 0 on 32-bit */
address = vma->vm_start;
} else {
@@ -1127,7 +1130,8 @@ static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw)
return pvmw->address + PAGE_SIZE;
pgoff = pvmw->pgoff + pvmw->nr_pages;
- address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ address = vma->vm_start +
+ ((pgoff - vma_start_pgoff(vma)) << PAGE_SHIFT);
/* Check for address beyond vma (or wrapped through 0?) */
if (address < vma->vm_start || address > vma->vm_end)
address = vma->vm_end;
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 912be3daf37e..45e8245d80da 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2150,7 +2150,8 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
spinlock_t *ptl;
bool success = false;
- addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ addr = vma->vm_start +
+ ((pgoff - vma_start_pgoff(vma)) << PAGE_SHIFT);
if (addr & ~HPAGE_PMD_MASK ||
vma->vm_end < addr + HPAGE_PMD_SIZE)
continue;
diff --git a/mm/madvise.c b/mm/madvise.c
index 9292f60b19aa..917f764fef80 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -253,7 +253,7 @@ static void shmem_swapin_range(struct vm_area_struct *vma,
continue;
addr = vma->vm_start +
- ((xas.xa_index - vma->vm_pgoff) << PAGE_SHIFT);
+ ((xas.xa_index - vma_start_pgoff(vma)) << PAGE_SHIFT);
xas_pause(&xas);
rcu_read_unlock();
@@ -318,7 +318,7 @@ static long madvise_willneed(struct madvise_behavior *madv_behavior)
mark_mmap_lock_dropped(madv_behavior);
get_file(file);
offset = (loff_t)(start - vma->vm_start)
- + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ + ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT);
mmap_read_unlock(mm);
vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED);
fput(file);
@@ -1022,7 +1022,7 @@ static long madvise_remove(struct madvise_behavior *madv_behavior)
return -EACCES;
offset = (loff_t)(start - vma->vm_start)
- + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ + ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT);
/*
* Filesystem's fallocate may need to take i_rwsem. We need to
diff --git a/mm/mapping_dirty_helpers.c b/mm/mapping_dirty_helpers.c
index 737c407f4081..e0efa36e0a07 100644
--- a/mm/mapping_dirty_helpers.c
+++ b/mm/mapping_dirty_helpers.c
@@ -95,7 +95,7 @@ static int clean_record_pte(pte_t *pte, unsigned long addr,
if (pte_dirty(ptent)) {
pgoff_t pgoff = ((addr - walk->vma->vm_start) >> PAGE_SHIFT) +
- walk->vma->vm_pgoff - cwalk->bitmap_pgoff;
+ vma_start_pgoff(walk->vma) - cwalk->bitmap_pgoff;
pte_t old_pte = ptep_modify_prot_start(walk->vma, addr, pte);
ptent = pte_mkclean(old_pte);
diff --git a/mm/memory.c b/mm/memory.c
index b7e9a7e53516..fb7a246487ac 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -725,10 +725,10 @@ static inline struct page *__vm_normal_page(struct vm_area_struct *vma,
if (!pfn_valid(pfn))
return NULL;
} else {
- unsigned long off = (addr - vma->vm_start) >> PAGE_SHIFT;
+ const pgoff_t index = linear_page_index(vma, addr);
/* Only CoW'ed anon folios are "normal". */
- if (pfn == vma->vm_pgoff + off)
+ if (pfn == index)
return NULL;
if (!is_cow_mapping(vma->vm_flags))
return NULL;
@@ -2663,7 +2663,7 @@ static int __vm_map_pages(struct vm_area_struct *vma, struct page **pages,
int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
unsigned long num)
{
- return __vm_map_pages(vma, pages, num, vma->vm_pgoff);
+ return __vm_map_pages(vma, pages, num, vma_start_pgoff(vma));
}
EXPORT_SYMBOL(vm_map_pages);
@@ -3318,7 +3318,8 @@ int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long
unsigned long pfn;
int err;
- err = __simple_ioremap_prep(vm_len, vma->vm_pgoff, start, len, &pfn);
+ err = __simple_ioremap_prep(vm_len, vma_start_pgoff(vma), start, len,
+ &pfn);
if (err)
return err;
@@ -4366,15 +4367,15 @@ static inline void unmap_mapping_range_tree(struct address_space *mapping,
struct zap_details *details)
{
struct vm_area_struct *vma;
- unsigned long start, size;
struct mmu_gather tlb;
mapping_rmap_tree_foreach(vma, mapping, first_index, last_index) {
- const pgoff_t start_idx = max(first_index, vma->vm_pgoff);
+ const pgoff_t start_idx = max(first_index, vma_start_pgoff(vma));
const pgoff_t end_idx = min(last_index, vma_last_pgoff(vma)) + 1;
-
- start = vma->vm_start + ((start_idx - vma->vm_pgoff) << PAGE_SHIFT);
- size = (end_idx - start_idx) << PAGE_SHIFT;
+ const pgoff_t offset = start_idx - vma_start_pgoff(vma);
+ const unsigned long offset_bytes = offset << PAGE_SHIFT;
+ const unsigned long start = vma->vm_start + offset_bytes;
+ const unsigned long size = (end_idx - start_idx) << PAGE_SHIFT;
tlb_gather_mmu(&tlb, vma->vm_mm);
zap_vma_range_batched(&tlb, vma, start, size, details);
@@ -5712,7 +5713,7 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
} else if (nr_pages > 1) {
pgoff_t idx = folio_page_idx(folio, page);
/* The page offset of vmf->address within the VMA. */
- pgoff_t vma_off = vmf->pgoff - vmf->vma->vm_pgoff;
+ pgoff_t vma_off = vmf->pgoff - vma_start_pgoff(vmf->vma);
/* The index of the entry in the pagetable for fault page. */
pgoff_t pte_off = pte_index(vmf->address);
@@ -5824,7 +5825,7 @@ static vm_fault_t do_fault_around(struct vm_fault *vmf)
pgoff_t nr_pages = READ_ONCE(fault_around_pages);
pgoff_t pte_off = pte_index(vmf->address);
/* The page offset of vmf->address within the VMA. */
- pgoff_t vma_off = vmf->pgoff - vmf->vma->vm_pgoff;
+ pgoff_t vma_off = vmf->pgoff - vma_start_pgoff(vmf->vma);
pgoff_t from_pte, to_pte;
vm_fault_t ret;
@@ -7352,7 +7353,7 @@ void print_vma_addr(char *prefix, unsigned long ip)
if (vma && vma->vm_file) {
struct file *f = vma->vm_file;
ip -= vma->vm_start;
- ip += vma->vm_pgoff << PAGE_SHIFT;
+ ip += vma_start_pgoff(vma) << PAGE_SHIFT;
printk("%s%pD[%lx,%lx+%lx]", prefix, f, ip,
vma->vm_start,
vma->vm_end - vma->vm_start);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 914f81863db5..bf6608309cea 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2049,8 +2049,8 @@ struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
pol = get_task_policy(current);
if (pol->mode == MPOL_INTERLEAVE ||
pol->mode == MPOL_WEIGHTED_INTERLEAVE) {
- *ilx += vma->vm_pgoff >> order;
- *ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order);
+ *ilx += vma_start_pgoff(vma) >> order;
+ *ilx += linear_page_delta(vma, addr) >> order;
}
return pol;
}
@@ -3244,16 +3244,17 @@ EXPORT_SYMBOL_FOR_MODULES(mpol_shared_policy_init, "kvm");
int mpol_set_shared_policy(struct shared_policy *sp,
struct vm_area_struct *vma, struct mempolicy *pol)
{
- int err;
+ const pgoff_t pgoff = vma_start_pgoff(vma);
+ const pgoff_t pgoff_end = vma_end_pgoff(vma);
struct sp_node *new = NULL;
- unsigned long sz = vma_pages(vma);
+ int err;
if (pol) {
- new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, pol);
+ new = sp_alloc(pgoff, pgoff_end, pol);
if (!new)
return -ENOMEM;
}
- err = shared_policy_replace(sp, vma->vm_pgoff, vma->vm_pgoff + sz, new);
+ err = shared_policy_replace(sp, pgoff, pgoff_end, new);
if (err && new)
sp_free(new);
return err;
diff --git a/mm/mremap.c b/mm/mremap.c
index 8a46ec5831c8..384ef4cc2195 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -957,8 +957,7 @@ static unsigned long vrm_set_new_addr(struct vma_remap_struct *vrm)
struct vm_area_struct *vma = vrm->vma;
unsigned long map_flags = 0;
/* Page Offset _into_ the VMA. */
- pgoff_t internal_pgoff = (vrm->addr - vma->vm_start) >> PAGE_SHIFT;
- pgoff_t pgoff = vma->vm_pgoff + internal_pgoff;
+ const pgoff_t pgoff = linear_page_index(vma, vrm->addr);
unsigned long new_addr = vrm_implies_new_addr(vrm) ? vrm->new_addr : 0;
unsigned long res;
@@ -1264,12 +1263,10 @@ static void unmap_source_vma(struct vma_remap_struct *vrm)
static int copy_vma_and_data(struct vma_remap_struct *vrm,
struct vm_area_struct **new_vma_ptr)
{
- unsigned long internal_offset = vrm->addr - vrm->vma->vm_start;
- unsigned long internal_pgoff = internal_offset >> PAGE_SHIFT;
- unsigned long new_pgoff = vrm->vma->vm_pgoff + internal_pgoff;
- unsigned long moved_len;
+ const unsigned long new_pgoff = linear_page_index(vrm->vma, vrm->addr);
struct vm_area_struct *vma = vrm->vma;
struct vm_area_struct *new_vma;
+ unsigned long moved_len;
int err = 0;
PAGETABLE_MOVE(pmc, NULL, NULL, vrm->addr, vrm->new_addr, vrm->old_len);
@@ -1811,8 +1808,7 @@ static int check_prep_vma(struct vma_remap_struct *vrm)
vrm->populate_expand = true;
/* Need to be careful about a growing mapping */
- pgoff = (addr - vma->vm_start) >> PAGE_SHIFT;
- pgoff += vma->vm_pgoff;
+ pgoff = linear_page_index(vma, addr);
if (pgoff + (new_len >> PAGE_SHIFT) < pgoff)
return -EINVAL;
diff --git a/mm/msync.c b/mm/msync.c
index ac4c9bfea2e7..90b491a27a14 100644
--- a/mm/msync.c
+++ b/mm/msync.c
@@ -12,6 +12,7 @@
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/file.h>
+#include <linux/pagemap.h>
#include <linux/syscalls.h>
#include <linux/sched.h>
@@ -85,8 +86,7 @@ SYSCALL_DEFINE3(msync, unsigned long, start, size_t, len, int, flags)
goto out_unlock;
}
file = vma->vm_file;
- fstart = (start - vma->vm_start) +
- ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ fstart = (loff_t)linear_page_index(vma, start) << PAGE_SHIFT;
fend = fstart + (min(end, vma->vm_end) - start) - 1;
start = vma->vm_end;
if ((flags & MS_SYNC) && file &&
diff --git a/mm/nommu.c b/mm/nommu.c
index f51a4a375c8c..52074ea90acb 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -975,7 +975,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
/* read the contents of a file into the copy */
loff_t fpos;
- fpos = vma->vm_pgoff;
+ fpos = vma_start_pgoff(vma);
fpos <<= PAGE_SHIFT;
ret = kernel_read(vma->vm_file, base, len, &fpos);
@@ -1378,7 +1378,8 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
delete_nommu_region(vma->vm_region);
if (new_below) {
vma->vm_region->vm_start = vma->vm_start = addr;
- vma->vm_region->vm_pgoff = vma->vm_pgoff += npages;
+ vma->vm_pgoff += npages;
+ vma->vm_region->vm_pgoff = vma_start_pgoff(vma);
} else {
vma->vm_region->vm_end = vma->vm_end = addr;
vma->vm_region->vm_top = addr;
@@ -1630,7 +1631,7 @@ int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long
unsigned long pfn = start >> PAGE_SHIFT;
unsigned long vm_len = vma->vm_end - vma->vm_start;
- pfn += vma->vm_pgoff;
+ pfn += vma_start_pgoff(vma);
return io_remap_pfn_range(vma, vma->vm_start, pfn, vm_len, vma->vm_page_prot);
}
EXPORT_SYMBOL(vm_iomap_memory);
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index 7e7819cf5a3a..dd854c734877 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -813,7 +813,7 @@ int walk_page_mapping(struct address_space *mapping, pgoff_t first_index,
mapping_rmap_tree_foreach(vma, mapping, first_index,
first_index + nr - 1) {
/* Clip to the vma */
- vba = vma->vm_pgoff;
+ vba = vma_start_pgoff(vma);
vea = vba + vma_pages(vma);
cba = first_index;
cba = max(cba, vba);
diff --git a/mm/shmem.c b/mm/shmem.c
index 3fb6dbbfa20b..c8e2011e0ce6 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1032,6 +1032,8 @@ unsigned long shmem_swap_usage(struct vm_area_struct *vma)
struct inode *inode = file_inode(vma->vm_file);
struct shmem_inode_info *info = SHMEM_I(inode);
struct address_space *mapping = inode->i_mapping;
+ const pgoff_t pgoff = vma_start_pgoff(vma);
+ const pgoff_t pgoff_end = vma_end_pgoff(vma);
unsigned long swapped;
/* Be careful as we don't hold info->lock */
@@ -1045,12 +1047,11 @@ unsigned long shmem_swap_usage(struct vm_area_struct *vma)
if (!swapped)
return 0;
- if (!vma->vm_pgoff && vma->vm_end - vma->vm_start >= inode->i_size)
+ if (!pgoff && vma->vm_end - vma->vm_start >= inode->i_size)
return swapped << PAGE_SHIFT;
/* Here comes the more involved part */
- return shmem_partial_swap_usage(mapping, vma->vm_pgoff,
- vma->vm_pgoff + vma_pages(vma));
+ return shmem_partial_swap_usage(mapping, pgoff, pgoff_end);
}
/*
@@ -2840,7 +2841,7 @@ static struct mempolicy *shmem_get_policy(struct vm_area_struct *vma,
* by page order, as in shmem_get_pgoff_policy() and get_vma_policy()).
*/
*ilx = inode->i_ino;
- index = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+ index = linear_page_index(vma, addr);
return mpol_shared_policy_lookup(&SHMEM_I(inode)->policy, index);
}
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 73f32299453b..8fd24c8b428e 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -481,7 +481,7 @@ static void mfill_retry_state_save(struct mfill_retry_state *s,
{
s->flags = vma_flags_and_mask(&vma->flags, MFILL_RETRY_STATE_VMA_FLAGS);
s->ops = vma_uffd_ops(vma);
- s->pgoff = vma->vm_pgoff;
+ s->pgoff = vma_start_pgoff(vma);
if (vma->vm_file)
s->file = get_file(vma->vm_file);
@@ -507,7 +507,7 @@ static bool mfill_retry_state_changed(struct mfill_retry_state *state,
/* VMA was file backed, but file, inode or offset has changed */
if (!vma->vm_file || vma->vm_file->f_inode != state->file->f_inode ||
- state->file != vma->vm_file || vma->vm_pgoff != state->pgoff)
+ state->file != vma->vm_file || vma_start_pgoff(vma) != state->pgoff)
return true;
return false;
diff --git a/mm/util.c b/mm/util.c
index 34cb43b3eaa4..5090457542ca 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -1188,7 +1188,7 @@ void compat_set_desc_from_vma(struct vm_area_desc *desc,
desc->start = vma->vm_start;
desc->end = vma->vm_end;
- desc->pgoff = vma->vm_pgoff;
+ desc->pgoff = vma_start_pgoff(vma);
desc->vm_file = vma->vm_file;
desc->vma_flags = vma->flags;
desc->page_prot = vma->vm_page_prot;
@@ -1379,7 +1379,7 @@ static int call_vma_mapped(struct vm_area_struct *vma)
if (!vm_ops || !vm_ops->mapped)
return 0;
- err = vm_ops->mapped(vma->vm_start, vma->vm_end, vma->vm_pgoff,
+ err = vm_ops->mapped(vma->vm_start, vma->vm_end, vma_start_pgoff(vma),
vma->vm_file, &vm_private_data);
if (err)
return err;
diff --git a/mm/vma.c b/mm/vma.c
index 5d5e60ea8a25..4a4d096ba86a 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -967,10 +967,9 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
* prev middle next
* extend delete delete
*/
-
vmg->start = prev->vm_start;
vmg->end = next->vm_end;
- vmg->pgoff = prev->vm_pgoff;
+ vmg->pgoff = vma_start_pgoff(prev);
/*
* We already ensured anon_vma compatibility above, so now it's
@@ -987,9 +986,8 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
* prev middle
* extend shrink/delete
*/
-
vmg->start = prev->vm_start;
- vmg->pgoff = prev->vm_pgoff;
+ vmg->pgoff = vma_start_pgoff(prev);
if (!vmg->__remove_middle)
vmg->__adjust_middle_start = true;
@@ -1011,13 +1009,13 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
if (vmg->__remove_middle) {
vmg->end = next->vm_end;
- vmg->pgoff = next->vm_pgoff - pglen;
+ vmg->pgoff = vma_start_pgoff(next) - pglen;
} else {
/* We shrink middle and expand next. */
vmg->__adjust_next_start = true;
vmg->start = middle->vm_start;
vmg->end = start;
- vmg->pgoff = middle->vm_pgoff;
+ vmg->pgoff = vma_start_pgoff(middle);
}
err = dup_anon_vma(next, middle, &anon_dup);
@@ -1126,7 +1124,7 @@ struct vm_area_struct *vma_merge_new_range(struct vma_merge_struct *vmg)
if (can_merge_left) {
vmg->start = prev->vm_start;
vmg->target = prev;
- vmg->pgoff = prev->vm_pgoff;
+ vmg->pgoff = vma_start_pgoff(prev);
/*
* If this merge would result in removal of the next VMA but we
@@ -1957,7 +1955,8 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
VM_BUG_ON_VMA(faulted_in_anon_vma, new_vma);
*vmap = vma = new_vma;
}
- *need_rmap_locks = (new_vma->vm_pgoff <= vma->vm_pgoff);
+ *need_rmap_locks =
+ (vma_start_pgoff(new_vma) <= vma_start_pgoff(vma));
} else {
new_vma = vm_area_dup(vma);
if (!new_vma)
diff --git a/mm/vma_exec.c b/mm/vma_exec.c
index 5cee8b7efa0f..e3644a3042e2 100644
--- a/mm/vma_exec.c
+++ b/mm/vma_exec.c
@@ -37,7 +37,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift)
unsigned long new_end = old_end - shift;
VMA_ITERATOR(vmi, mm, new_start);
VMG_STATE(vmg, mm, &vmi, new_start, old_end, EMPTY_VMA_FLAGS,
- vma->vm_pgoff);
+ vma_start_pgoff(vma));
struct vm_area_struct *next;
struct mmu_gather tlb;
PAGETABLE_MOVE(pmc, vma, vma, old_start, new_start, length);
@@ -89,7 +89,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift)
vma_prev(&vmi);
/* Shrink the vma to just the new range */
- return vma_shrink(&vmi, vma, new_start, new_end, vma->vm_pgoff);
+ return vma_shrink(&vmi, vma, new_start, new_end, vma_start_pgoff(vma));
}
/*
diff --git a/mm/vma_init.c b/mm/vma_init.c
index 3c0b65950510..a459669a1654 100644
--- a/mm/vma_init.c
+++ b/mm/vma_init.c
@@ -46,7 +46,7 @@ static void vm_area_init_from(const struct vm_area_struct *src,
dest->vm_start = src->vm_start;
dest->vm_end = src->vm_end;
dest->anon_vma = src->anon_vma;
- dest->vm_pgoff = src->vm_pgoff;
+ dest->vm_pgoff = vma_start_pgoff(src);
dest->vm_file = src->vm_file;
dest->vm_private_data = src->vm_private_data;
vm_flags_init(dest, src->vm_flags);
--
2.55.0
^ permalink raw reply related
* [PATCH v2 19/33] mm: prefer vma_[start,end]_pgoff() to vma->vm_pgoff in kernel/
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Be consistent in using vma_start_pgoff() and vma_end_pgoff(), which clearly
indicates which part of the VMA the page offset refers to and aids
greppability.
This is part of a broader series laying the ground to provide a virtual
page offset for MAP_PRIVATE-file backed anon folios.
No functional change intended.
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> # for kernel/dma
Reviewed-by: Gregory Price <gourry@gourry.net>
Acked-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
kernel/dma/coherent.c | 7 ++++---
kernel/dma/direct.c | 6 ++++--
kernel/dma/mapping.c | 8 +++++---
kernel/dma/ops_helpers.c | 4 ++--
kernel/events/core.c | 20 +++++++++++---------
kernel/events/uprobes.c | 11 +++++++----
kernel/kcov.c | 2 +-
kernel/trace/ring_buffer.c | 3 ++-
8 files changed, 36 insertions(+), 25 deletions(-)
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index bcdc0f76d2e8..2d3195eb7e83 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -236,14 +236,15 @@ static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
{
if (mem && vaddr >= mem->virt_base && vaddr + size <=
(mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) {
- unsigned long off = vma->vm_pgoff;
+ const pgoff_t pgoff_start = vma_start_pgoff(vma);
+ const pgoff_t pgoff_end = vma_end_pgoff(vma);
int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
unsigned long user_count = vma_pages(vma);
int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
*ret = -ENXIO;
- if (off < count && user_count <= count - off) {
- unsigned long pfn = mem->pfn_base + start + off;
+ if (pgoff_start < count && pgoff_end <= count) {
+ unsigned long pfn = mem->pfn_base + start + pgoff_start;
*ret = remap_pfn_range(vma, vma->vm_start, pfn,
user_count << PAGE_SHIFT,
vma->vm_page_prot);
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 4391b797d4db..436310d6e4a2 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -534,6 +534,8 @@ int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
unsigned long user_count = vma_pages(vma);
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
unsigned long pfn = PHYS_PFN(dma_to_phys(dev, dma_addr));
+ const pgoff_t pgoff_start = vma_start_pgoff(vma);
+ const pgoff_t pgoff_end = vma_end_pgoff(vma);
int ret = -ENXIO;
vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
@@ -545,9 +547,9 @@ int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
if (dma_mmap_from_global_coherent(vma, cpu_addr, size, &ret))
return ret;
- if (vma->vm_pgoff >= count || user_count > count - vma->vm_pgoff)
+ if (pgoff_start >= count || pgoff_end > count)
return -ENXIO;
- return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
+ return remap_pfn_range(vma, vma->vm_start, pfn + pgoff_start,
user_count << PAGE_SHIFT, vma->vm_page_prot);
}
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 4fe04669e5e6..c986639044e9 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -761,12 +761,14 @@ EXPORT_SYMBOL_GPL(dma_free_pages);
int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
size_t size, struct page *page)
{
- unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ const pgoff_t pgoff_start = vma_start_pgoff(vma);
+ const pgoff_t pgoff_end = vma_end_pgoff(vma);
+ const unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
- if (vma->vm_pgoff >= count || vma_pages(vma) > count - vma->vm_pgoff)
+ if (pgoff_start >= count || pgoff_end > count)
return -ENXIO;
return remap_pfn_range(vma, vma->vm_start,
- page_to_pfn(page) + vma->vm_pgoff,
+ page_to_pfn(page) + pgoff_start,
vma_pages(vma) << PAGE_SHIFT, vma->vm_page_prot);
}
EXPORT_SYMBOL_GPL(dma_mmap_pages);
diff --git a/kernel/dma/ops_helpers.c b/kernel/dma/ops_helpers.c
index 20caf9cabf69..6b5f9208d31c 100644
--- a/kernel/dma/ops_helpers.c
+++ b/kernel/dma/ops_helpers.c
@@ -39,7 +39,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
#ifdef CONFIG_MMU
unsigned long user_count = vma_pages(vma);
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
- unsigned long off = vma->vm_pgoff;
+ unsigned long off = vma_start_pgoff(vma);
struct page *page = dma_common_vaddr_to_page(cpu_addr);
int ret = -ENXIO;
@@ -52,7 +52,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
return -ENXIO;
return remap_pfn_range(vma, vma->vm_start,
- page_to_pfn(page) + vma->vm_pgoff,
+ page_to_pfn(page) + vma_start_pgoff(vma),
user_count << PAGE_SHIFT, vma->vm_page_prot);
#else
return -ENXIO;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index d7f3e2c2ecb1..44a092db5d58 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -6998,7 +6998,7 @@ static void perf_mmap_open(struct vm_area_struct *vma)
refcount_inc(&event->mmap_count);
refcount_inc(&event->rb->mmap_count);
- if (vma->vm_pgoff)
+ if (vma_start_pgoff(vma))
refcount_inc(&event->rb->aux_mmap_count);
if (mapped)
@@ -7032,7 +7032,7 @@ static void perf_mmap_close(struct vm_area_struct *vma)
* The AUX buffer is strictly a sub-buffer, serialize using aux_mutex
* to avoid complications.
*/
- if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff &&
+ if (rb_has_aux(rb) && vma_start_pgoff(vma) == rb->aux_pgoff &&
refcount_dec_and_mutex_lock(&rb->aux_mmap_count, &rb->aux_mutex)) {
/*
* Stop all AUX events that are writing to this buffer,
@@ -7190,7 +7190,8 @@ static int map_range(struct perf_buffer *rb, struct vm_area_struct *vma)
*/
for (pagenum = 0; pagenum < nr_pages; pagenum++) {
unsigned long va = vma->vm_start + PAGE_SIZE * pagenum;
- struct page *page = perf_mmap_to_page(rb, vma->vm_pgoff + pagenum);
+ struct page *page = perf_mmap_to_page(rb,
+ vma_start_pgoff(vma) + pagenum);
if (page == NULL) {
err = -EINVAL;
@@ -7344,6 +7345,7 @@ static int perf_mmap_rb(struct vm_area_struct *vma, struct perf_event *event,
static int perf_mmap_aux(struct vm_area_struct *vma, struct perf_event *event,
unsigned long nr_pages)
{
+ const pgoff_t pgoff_start = vma_start_pgoff(vma);
long extra = 0, user_extra = nr_pages;
u64 aux_offset, aux_size;
struct perf_buffer *rb;
@@ -7366,11 +7368,11 @@ static int perf_mmap_aux(struct vm_area_struct *vma, struct perf_event *event,
if (aux_offset < perf_data_size(rb) + PAGE_SIZE)
return -EINVAL;
- if (aux_offset != vma->vm_pgoff << PAGE_SHIFT)
+ if (aux_offset != pgoff_start << PAGE_SHIFT)
return -EINVAL;
/* already mapped with a different offset */
- if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff)
+ if (rb_has_aux(rb) && rb->aux_pgoff != pgoff_start)
return -EINVAL;
if (aux_size != nr_pages * PAGE_SIZE)
@@ -7400,7 +7402,7 @@ static int perf_mmap_aux(struct vm_area_struct *vma, struct perf_event *event,
if (vma->vm_flags & VM_WRITE)
rb_flags |= RING_BUFFER_WRITABLE;
- ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages,
+ ret = rb_alloc_aux(rb, event, pgoff_start, nr_pages,
event->attr.aux_watermark, rb_flags);
if (ret) {
refcount_dec(&rb->mmap_count);
@@ -7457,7 +7459,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
if (event->state <= PERF_EVENT_STATE_REVOKED)
return -ENODEV;
- if (vma->vm_pgoff == 0)
+ if (!vma_start_pgoff(vma))
ret = perf_mmap_rb(vma, event, nr_pages);
else
ret = perf_mmap_aux(vma, event, nr_pages);
@@ -9884,7 +9886,7 @@ static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter,
struct perf_addr_filter_range *fr)
{
unsigned long vma_size = vma->vm_end - vma->vm_start;
- unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
+ unsigned long off = vma_start_pgoff(vma) << PAGE_SHIFT;
struct file *file = vma->vm_file;
if (!perf_addr_filter_match(filter, file, off, vma_size))
@@ -9974,7 +9976,7 @@ void perf_event_mmap(struct vm_area_struct *vma)
/* .tid */
.start = vma->vm_start,
.len = vma->vm_end - vma->vm_start,
- .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT,
+ .pgoff = (u64)vma_start_pgoff(vma) << PAGE_SHIFT,
},
/* .maj (attr_mmap2 only) */
/* .min (attr_mmap2 only) */
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index ac340a703d06..ae2f3b9f8d50 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -144,12 +144,14 @@ static bool valid_vma(struct vm_area_struct *vma, bool is_register)
static unsigned long offset_to_vaddr(struct vm_area_struct *vma, loff_t offset)
{
- return vma->vm_start + offset - ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ return vma->vm_start + offset -
+ ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT);
}
static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr)
{
- return ((loff_t)vma->vm_pgoff << PAGE_SHIFT) + (vaddr - vma->vm_start);
+ return ((loff_t)vma_start_pgoff(vma) << PAGE_SHIFT) +
+ (vaddr - vma->vm_start);
}
/**
@@ -1482,7 +1484,7 @@ static int unapply_uprobe(struct uprobe *uprobe, struct mm_struct *mm)
file_inode(vma->vm_file) != uprobe->inode)
continue;
- offset = (loff_t)vma->vm_pgoff << PAGE_SHIFT;
+ offset = (loff_t)vma_start_pgoff(vma) << PAGE_SHIFT;
if (uprobe->offset < offset ||
uprobe->offset >= offset + vma->vm_end - vma->vm_start)
continue;
@@ -2453,7 +2455,8 @@ static struct uprobe *find_active_uprobe_speculative(unsigned long bp_vaddr)
if (!vm_file)
return NULL;
- offset = (loff_t)(vma->vm_pgoff << PAGE_SHIFT) + (bp_vaddr - vma->vm_start);
+ offset = (loff_t)(vma_start_pgoff(vma) << PAGE_SHIFT) +
+ (bp_vaddr - vma->vm_start);
uprobe = find_uprobe_rcu(vm_file->f_inode, offset);
if (!uprobe)
return NULL;
diff --git a/kernel/kcov.c b/kernel/kcov.c
index 1df373fb562b..b19b473c366a 100644
--- a/kernel/kcov.c
+++ b/kernel/kcov.c
@@ -512,7 +512,7 @@ static int kcov_mmap(struct file *filep, struct vm_area_struct *vma)
spin_lock_irqsave(&kcov->lock, flags);
size = kcov->size * sizeof(unsigned long);
- if (kcov->area == NULL || vma->vm_pgoff != 0 ||
+ if (kcov->area == NULL || vma_start_pgoff(vma) ||
vma->vm_end - vma->vm_start != size) {
res = -EINVAL;
goto exit;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 56a328e94395..dfa493d54ef9 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -7613,7 +7613,8 @@ static int __rb_inc_dec_mapped(struct ring_buffer_per_cpu *cpu_buffer,
static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer,
struct vm_area_struct *vma)
{
- unsigned long nr_subbufs, nr_pages, nr_vma_pages, pgoff = vma->vm_pgoff;
+ unsigned long nr_subbufs, nr_pages, nr_vma_pages;
+ pgoff_t pgoff = vma_start_pgoff(vma);
unsigned int subbuf_pages, subbuf_order;
struct page **pages __free(kfree) = NULL;
int p = 0, s = 0;
--
2.55.0
^ permalink raw reply related
* [PATCH v2 20/33] mm/vma: remove duplicative vma_pgoff_offset() helper
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
This is doing what linear_page_index() does, so eliminate it and replace it
with linear_page_index().
Update the VMA userland tests to reflect this change.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.h | 9 +--------
tools/testing/vma/include/dup.h | 16 ++++++++++++++++
2 files changed, 17 insertions(+), 8 deletions(-)
diff --git a/mm/vma.h b/mm/vma.h
index 527716c8739d..2342516ce00e 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -247,13 +247,6 @@ static inline pgoff_t vmg_end_pgoff(const struct vma_merge_struct *vmg)
return vmg_start_pgoff(vmg) + vmg_pages(vmg);
}
-/* Assumes addr >= vma->vm_start. */
-static inline pgoff_t vma_pgoff_offset(struct vm_area_struct *vma,
- unsigned long addr)
-{
- return vma->vm_pgoff + PHYS_PFN(addr - vma->vm_start);
-}
-
#define VMG_STATE(name, mm_, vmi_, start_, end_, vma_flags_, pgoff_) \
struct vma_merge_struct name = { \
.mm = mm_, \
@@ -275,7 +268,7 @@ static inline pgoff_t vma_pgoff_offset(struct vm_area_struct *vma,
.start = start_, \
.end = end_, \
.vm_flags = vma_->vm_flags, \
- .pgoff = vma_pgoff_offset(vma_, start_), \
+ .pgoff = linear_page_index(vma_, start_), \
.file = vma_->vm_file, \
.anon_vma = vma_->anon_vma, \
.policy = vma_policy(vma_), \
diff --git a/tools/testing/vma/include/dup.h b/tools/testing/vma/include/dup.h
index 535747d7fee4..7ed165c8d9bc 100644
--- a/tools/testing/vma/include/dup.h
+++ b/tools/testing/vma/include/dup.h
@@ -1548,3 +1548,19 @@ static inline pgprot_t vma_get_page_prot(vma_flags_t vma_flags)
return vm_get_page_prot(vm_flags);
}
+
+static inline pgoff_t linear_page_delta(const struct vm_area_struct *vma,
+ const unsigned long address)
+{
+ return (address - vma->vm_start) >> PAGE_SHIFT;
+}
+
+static inline pgoff_t linear_page_index(const struct vm_area_struct *vma,
+ const unsigned long address)
+{
+ pgoff_t pgoff;
+
+ pgoff = linear_page_delta(vma, address);
+ pgoff += vma_start_pgoff(vma);
+ return pgoff;
+}
--
2.55.0
^ permalink raw reply related
* [PATCH v2 21/33] mm: use linear_page_[index, delta]() consistently
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King, Kai Huang, Ackerley Tng
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
There are a number of places where we open code what linear_page_index()
and linear_page_delta() calculate.
Replace this code with the appropriate functions for consistency.
No functional change intended.
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> # for DRM
Acked-by: Kai Huang <kai.huang@intel.com> # for sgx
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Pedro Falcato <pfalcato@suse.de> # for mm
Reviewed-by: Ackerley Tng <ackerleytng@google.com> # for guest_memfd
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
arch/arm/mm/fault-armv.c | 2 +-
arch/x86/kernel/cpu/sgx/virt.c | 3 ++-
drivers/gpu/drm/etnaviv/etnaviv_gem.c | 3 ++-
drivers/gpu/drm/gma500/gem.c | 2 +-
drivers/gpu/drm/msm/msm_gem.c | 3 ++-
drivers/gpu/drm/omapdrm/omap_gem.c | 5 +++--
drivers/gpu/drm/tegra/gem.c | 3 ++-
drivers/gpu/drm/ttm/ttm_bo_vm.c | 7 ++++---
drivers/vfio/pci/nvgrace-gpu/main.c | 3 ++-
drivers/vfio/pci/vfio_pci_core.c | 3 ++-
mm/nommu.c | 2 +-
mm/vma.c | 2 +-
virt/kvm/guest_memfd.c | 2 +-
13 files changed, 24 insertions(+), 16 deletions(-)
diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c
index b505f1fd7984..2769b0f3325f 100644
--- a/arch/arm/mm/fault-armv.c
+++ b/arch/arm/mm/fault-armv.c
@@ -132,7 +132,7 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
pgoff_t pgoff;
int aliases = 0;
- pgoff = vma->vm_pgoff + ((addr - vma->vm_start) >> PAGE_SHIFT);
+ pgoff = linear_page_index(vma, addr);
/*
* If we have any shared mappings that are in the same mm
diff --git a/arch/x86/kernel/cpu/sgx/virt.c b/arch/x86/kernel/cpu/sgx/virt.c
index db6806c40483..6a1933ddc6fc 100644
--- a/arch/x86/kernel/cpu/sgx/virt.c
+++ b/arch/x86/kernel/cpu/sgx/virt.c
@@ -9,6 +9,7 @@
#include <linux/miscdevice.h>
#include <linux/mm.h>
#include <linux/mman.h>
+#include <linux/pagemap.h>
#include <linux/sched/mm.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
@@ -41,7 +42,7 @@ static int __sgx_vepc_fault(struct sgx_vepc *vepc,
WARN_ON(!mutex_is_locked(&vepc->lock));
/* Calculate index of EPC page in virtual EPC's page_array */
- index = vma->vm_pgoff + PFN_DOWN(addr - vma->vm_start);
+ index = linear_page_index(vma, addr);
epc_page = xa_load(&vepc->page_array, index);
if (epc_page)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
index b0436a1e103f..2e4d6d117ee2 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
@@ -6,6 +6,7 @@
#include <drm/drm_prime.h>
#include <drm/drm_print.h>
#include <linux/dma-mapping.h>
+#include <linux/pagemap.h>
#include <linux/shmem_fs.h>
#include <linux/spinlock.h>
#include <linux/vmalloc.h>
@@ -188,7 +189,7 @@ static vm_fault_t etnaviv_gem_fault(struct vm_fault *vmf)
}
/* We don't use vmf->pgoff since that has the fake offset: */
- pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ pgoff = linear_page_delta(vma, vmf->address);
pfn = page_to_pfn(pages[pgoff]);
diff --git a/drivers/gpu/drm/gma500/gem.c b/drivers/gpu/drm/gma500/gem.c
index 88f1e86c8903..2708e8c68f4c 100644
--- a/drivers/gpu/drm/gma500/gem.c
+++ b/drivers/gpu/drm/gma500/gem.c
@@ -288,7 +288,7 @@ static vm_fault_t psb_gem_fault(struct vm_fault *vmf)
/* Page relative to the VMA start - we must calculate this ourselves
because vmf->pgoff is the fake GEM offset */
- page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ page_offset = linear_page_delta(vma, vmf->address);
/* CPU view of the page, don't go via the GART for CPU writes */
if (pobj->stolen)
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index efd3d3c9a449..cbf723a5d86f 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -9,6 +9,7 @@
#include <linux/spinlock.h>
#include <linux/shmem_fs.h>
#include <linux/dma-buf.h>
+#include <linux/pagemap.h>
#include <drm/drm_dumb_buffers.h>
#include <drm/drm_prime.h>
@@ -360,7 +361,7 @@ static vm_fault_t msm_gem_fault(struct vm_fault *vmf)
}
/* We don't use vmf->pgoff since that has the fake offset: */
- pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ pgoff = linear_page_delta(vma, vmf->address);
pfn = page_to_pfn(pages[pgoff]);
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index 8e013e4f2c6b..00404fb6c29a 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -5,6 +5,7 @@
*/
#include <linux/dma-mapping.h>
+#include <linux/pagemap.h>
#include <linux/seq_file.h>
#include <linux/shmem_fs.h>
#include <linux/spinlock.h>
@@ -359,7 +360,7 @@ static vm_fault_t omap_gem_fault_1d(struct drm_gem_object *obj,
pgoff_t pgoff;
/* We don't use vmf->pgoff since that has the fake offset: */
- pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ pgoff = linear_page_delta(vma, vmf->address);
if (omap_obj->pages) {
omap_gem_cpu_sync_page(obj, pgoff);
@@ -407,7 +408,7 @@ static vm_fault_t omap_gem_fault_2d(struct drm_gem_object *obj,
const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE);
/* We don't use vmf->pgoff since that has the fake offset: */
- pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ pgoff = linear_page_delta(vma, vmf->address);
/*
* Actual address we start mapping at is rounded down to previous slot
diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index 436394e04812..1d8d27a5ea89 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -13,6 +13,7 @@
#include <linux/dma-buf.h>
#include <linux/iommu.h>
#include <linux/module.h>
+#include <linux/pagemap.h>
#include <linux/vmalloc.h>
#include <drm/drm_drv.h>
@@ -564,7 +565,7 @@ static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
if (!bo->pages)
return VM_FAULT_SIGBUS;
- offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
+ offset = linear_page_delta(vma, vmf->address);
page = bo->pages[offset];
return vmf_insert_page(vma, vmf->address, page);
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index a80510489c45..88babf435ac2 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -32,6 +32,7 @@
#define pr_fmt(fmt) "[TTM] " fmt
#include <linux/export.h>
+#include <linux/pagemap.h>
#include <drm/ttm/ttm_bo.h>
#include <drm/ttm/ttm_placement.h>
@@ -208,9 +209,9 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
if (unlikely(err != 0))
return VM_FAULT_SIGBUS;
- page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
- vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node);
- page_last = vma_pages(vma) + vma->vm_pgoff -
+ page_offset = linear_page_index(vma, address) -
+ drm_vma_node_start(&bo->base.vma_node);
+ page_last = vma_end_pgoff(vma) -
drm_vma_node_start(&bo->base.vma_node);
if (unlikely(page_offset >= PFN_UP(bo->base.size)))
diff --git a/drivers/vfio/pci/nvgrace-gpu/main.c b/drivers/vfio/pci/nvgrace-gpu/main.c
index d07dcacb76bd..963fd8ded20d 100644
--- a/drivers/vfio/pci/nvgrace-gpu/main.c
+++ b/drivers/vfio/pci/nvgrace-gpu/main.c
@@ -11,6 +11,7 @@
#include <linux/jiffies.h>
#include <linux/sched.h>
#include <linux/pci-p2pdma.h>
+#include <linux/pagemap.h>
#include <linux/pm_runtime.h>
#include <linux/memory-failure.h>
@@ -385,7 +386,7 @@ static unsigned long addr_to_pgoff(struct vm_area_struct *vma,
u64 pgoff = vma->vm_pgoff &
((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
- return ((addr - vma->vm_start) >> PAGE_SHIFT) + pgoff;
+ return linear_page_delta(vma, addr) + pgoff;
}
static vm_fault_t nvgrace_gpu_vfio_pci_huge_fault(struct vm_fault *vmf,
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index 3f11a9624b9c..a113c55845e1 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -20,6 +20,7 @@
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
+#include <linux/pagemap.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
@@ -1780,7 +1781,7 @@ static vm_fault_t vfio_pci_mmap_huge_fault(struct vm_fault *vmf,
struct vm_area_struct *vma = vmf->vma;
struct vfio_pci_core_device *vdev = vma->vm_private_data;
unsigned long addr = vmf->address & ~((PAGE_SIZE << order) - 1);
- unsigned long pgoff = (addr - vma->vm_start) >> PAGE_SHIFT;
+ unsigned long pgoff = linear_page_delta(vma, addr);
unsigned long pfn = vma_to_pfn(vma) + pgoff;
vm_fault_t ret = VM_FAULT_FALLBACK;
diff --git a/mm/nommu.c b/mm/nommu.c
index 52074ea90acb..c0a0869cd0d6 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1355,7 +1355,7 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
*region = *vma->vm_region;
new->vm_region = region;
- npages = (addr - vma->vm_start) >> PAGE_SHIFT;
+ npages = linear_page_delta(vma, addr);
if (new_below) {
region->vm_top = region->vm_end = new->vm_end = addr;
diff --git a/mm/vma.c b/mm/vma.c
index 4a4d096ba86a..7aa0149f076c 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -517,7 +517,7 @@ __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
new->vm_end = addr;
} else {
new->vm_start = addr;
- new->vm_pgoff += ((addr - vma->vm_start) >> PAGE_SHIFT);
+ new->vm_pgoff += linear_page_delta(vma, addr);
}
err = -ENOMEM;
diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index db57c5766ab6..f0e5da490866 100644
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -440,7 +440,7 @@ static int kvm_gmem_set_policy(struct vm_area_struct *vma, struct mempolicy *mpo
static struct mempolicy *kvm_gmem_get_policy(struct vm_area_struct *vma,
unsigned long addr, pgoff_t *ilx)
{
- pgoff_t pgoff = vma->vm_pgoff + ((addr - vma->vm_start) >> PAGE_SHIFT);
+ pgoff_t pgoff = linear_page_index(vma, addr);
struct inode *inode = file_inode(vma->vm_file);
*ilx = inode->i_ino;
--
2.55.0
^ permalink raw reply related
* [PATCH v2 22/33] mm/vma: introduce vma_assert_can_modify()
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
vma_assert_write_locked() and vma_assert_attached() are useful for their
own purposes, however VMA code absolutely does allow the modification of
non-write locked VMAs if they are at that point detached (i.e. unreachable
from anywhere).
It's therefore useful to be able to assert that a VMA is either
detached (modification doesn't matter) or write locked (you're explicitly
locked for modification).
Therefore introduce vma_assert_can_modify() for this purpose.
While we're here, make vma_is_attached() available generally - if
!CONFIG_PER_VMA_LOCK, then there's no sense in which a VMA is
detached (vma_mark_detached() is a noop), so have this default to true in
this case.
Also update VMA userland tests to reflect this change, correcting the
previously open-coded vma_assert_[attached,detached]() there.
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
include/linux/mmap_lock.h | 8 ++++++++
tools/testing/vma/include/dup.h | 15 +++++++++++++--
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h
index 04b8f61ece5d..d513286d8160 100644
--- a/include/linux/mmap_lock.h
+++ b/include/linux/mmap_lock.h
@@ -506,6 +506,8 @@ static inline __must_check
int vma_start_write_killable(struct vm_area_struct *vma) { return 0; }
static inline void vma_assert_write_locked(struct vm_area_struct *vma)
{ mmap_assert_write_locked(vma->vm_mm); }
+static inline bool vma_is_attached(struct vm_area_struct *vma)
+ { return true; }
static inline void vma_assert_attached(struct vm_area_struct *vma) {}
static inline void vma_assert_detached(struct vm_area_struct *vma) {}
static inline void vma_mark_attached(struct vm_area_struct *vma) {}
@@ -530,6 +532,12 @@ static inline void vma_assert_stabilised(struct vm_area_struct *vma)
#endif /* CONFIG_PER_VMA_LOCK */
+static inline void vma_assert_can_modify(struct vm_area_struct *vma)
+{
+ if (vma_is_attached(vma))
+ vma_assert_write_locked(vma);
+}
+
static inline void mmap_write_lock(struct mm_struct *mm)
{
__mmap_lock_trace_start_locking(mm, true);
diff --git a/tools/testing/vma/include/dup.h b/tools/testing/vma/include/dup.h
index 7ed165c8d9bc..e9ddc818f2c3 100644
--- a/tools/testing/vma/include/dup.h
+++ b/tools/testing/vma/include/dup.h
@@ -1163,6 +1163,11 @@ static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
return mas_find(&vmi->mas, ULONG_MAX);
}
+static inline bool vma_is_attached(struct vm_area_struct *vma)
+{
+ return refcount_read(&vma->vm_refcnt);
+}
+
/*
* WARNING: to avoid racing with vma_mark_attached()/vma_mark_detached(), these
* assertions should be made either under mmap_write_lock or when the object
@@ -1170,12 +1175,12 @@ static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
*/
static inline void vma_assert_attached(struct vm_area_struct *vma)
{
- WARN_ON_ONCE(!refcount_read(&vma->vm_refcnt));
+ WARN_ON_ONCE(!vma_is_attached(vma));
}
static inline void vma_assert_detached(struct vm_area_struct *vma)
{
- WARN_ON_ONCE(refcount_read(&vma->vm_refcnt));
+ WARN_ON_ONCE(vma_is_attached(vma));
}
static inline void vma_assert_write_locked(struct vm_area_struct *);
@@ -1564,3 +1569,9 @@ static inline pgoff_t linear_page_index(const struct vm_area_struct *vma,
pgoff += vma_start_pgoff(vma);
return pgoff;
}
+
+static inline void vma_assert_can_modify(struct vm_area_struct *vma)
+{
+ if (vma_is_attached(vma))
+ vma_assert_write_locked(vma);
+}
--
2.55.0
^ permalink raw reply related
* Re: [PATCH 29/30] tools/testing/vma: default VMA flag bits to 64-bit
From: Lorenzo Stoakes @ 2026-07-10 20:25 UTC (permalink / raw)
To: Gregory Price
Cc: Andrew Morton, Russell King, Dinh Nguyen, Simon Schuster,
James E . J . Bottomley, Helge Deller, Jarkko Sakkinen,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, x86,
Ian Abbott, H Hartley Sweeten, Lucas Stach, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Ankit Agrawal, Alex Williamson,
Alexander Viro, Christian Brauner, Dan Williams, Muchun Song,
Oscar Salvador, David Hildenbrand, Suren Baghdasaryan,
Liam R . Howlett, Matthew Wilcox, Marek Szyprowski,
Peter Zijlstra, Arnaldo Carvalho de Melo, Namhyung Kim,
Masami Hiramatsu, Oleg Nesterov, Steven Rostedt, SeongJae Park,
Miaohe Lin, Hugh Dickins, Mike Rapoport, Kees Cook, Paolo Bonzini,
linux-kernel, linux-arm-kernel, linux-parisc, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
linux-fsdevel, nvdimm, linux-mm, iommu, linux-perf-users,
linux-trace-kernel, kasan-dev, damon, Pedro Falcato, Rik van Riel,
Harry Yoo, Jann Horn
In-Reply-To: <alFT7lx8F04rN01D@gourry-fedora-PF4VCD3F>
On Fri, Jul 10, 2026 at 04:19:58PM -0400, Gregory Price wrote:
> On Mon, Jun 29, 2026 at 01:23:40PM +0100, Lorenzo Stoakes wrote:
> > With all of the sanitisers turned on, setting the VMA flag bits depth to
> > 128 by default results in overly long build times.
> >
> > Reduce this to 64 - we can always manipulate these later for testing of
> > larger bitmaps as needed.
> >
> > Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
>
> Seems like this causes instrumented inlining to go crazy.
>
> static inline void bitmap_or(...) {
> if (small_const_nbits(nbits))
> *dst = *src1 | *src2;
> else
> __bitmap_or(dst, src1, src2, nbits);
> ^^^^ this branch is being hit ^^^^
> }
>
> tl;dr: __bitmap_or() gets emitted and then the sanitizers have to
> instrument a ton of inlined functions instead of the compiler simply
> injecting a couple 'or' instructions.
>
> if you wanted to keep the coverage you could do something like
>
> # These can be varied to test different sizes.
> NUM_VMA_FLAG_BITS ?= 64
> NUM_MM_FLAG_BITS ?= 64
> CFLAGS += -DNUM_VMA_FLAG_BITS=$(NUM_VMA_FLAG_BITS) -DNUM_MM_FLAG_BITS=$(NUM_MM_FLAG_BITS)
>
> w/
>
> make NUM_VMA_FLAG_BITS=128
>
> would let you still test the branch but not by default.
Yeah I need to make it easier to set.
And that's a pity re: the sanitisers, the generated code should still be
efficient (will investigate some more over time) but yeah puts a lot more
pressure on the sanitisers for sure.
Is there a way maybe to configure the compiler to not instrument like that or
somehow derive things? Or maybe it's inherent... I am kinda fine with assuming
the bitmap stuff is OK!
>
> anyway:
>
> Reviewed-by: Gregory Price <gourry@gourry.net>
Sorry but I'm sending out the v2 I thought maybe you were done :|| and I'm so
tired with this heatwave + UK houses being like ovens in the summer (cold in the
winter!) that I just needed to get it sending.
Could you pop it over on the relevant patch on the v2? Once the sending stops,
b4 went crazy and added half the kernel so it's taking a while ;)
>
> ~Gregory
Cheers, Lorenzo
^ permalink raw reply
* [PATCH v2 23/33] mm/vma: add and use vma_[add/sub]_pgoff()
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Add helpers for adding or subtracting to a VMA's page offset, exposed
internally for VMA users within mm in mm/vma.h.
This is to lay the foundations for tracking anonymous page offset for
MAP_PRIVATE file-backed mappings, where adding and subtracting from this
value must be reflected in both the file and anonymous offsets.
These are used on VMA split and downward stack expansion.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/nommu.c | 6 ++++--
mm/vma.c | 6 +++---
mm/vma.h | 12 ++++++++++++
3 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/mm/nommu.c b/mm/nommu.c
index c0a0869cd0d6..2a0136f6081d 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -41,6 +41,7 @@
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include "internal.h"
+#include "vma.h"
unsigned long highest_memmap_pfn;
int heap_stack_gap = 0;
@@ -1361,7 +1362,8 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
region->vm_top = region->vm_end = new->vm_end = addr;
} else {
region->vm_start = new->vm_start = addr;
- region->vm_pgoff = new->vm_pgoff += npages;
+ vma_add_pgoff(new, npages);
+ region->vm_pgoff = vma_start_pgoff(new);
}
vma_iter_config(vmi, new->vm_start, new->vm_end);
@@ -1378,7 +1380,7 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
delete_nommu_region(vma->vm_region);
if (new_below) {
vma->vm_region->vm_start = vma->vm_start = addr;
- vma->vm_pgoff += npages;
+ vma_add_pgoff(vma, npages);
vma->vm_region->vm_pgoff = vma_start_pgoff(vma);
} else {
vma->vm_region->vm_end = vma->vm_end = addr;
diff --git a/mm/vma.c b/mm/vma.c
index 7aa0149f076c..bdd99ba56b4d 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -517,7 +517,7 @@ __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
new->vm_end = addr;
} else {
new->vm_start = addr;
- new->vm_pgoff += linear_page_delta(vma, addr);
+ vma_add_pgoff(new, linear_page_delta(vma, addr));
}
err = -ENOMEM;
@@ -556,7 +556,7 @@ __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
if (new_below) {
vma->vm_start = addr;
- vma->vm_pgoff += (addr - new->vm_start) >> PAGE_SHIFT;
+ vma_add_pgoff(vma, (addr - new->vm_start) >> PAGE_SHIFT);
} else {
vma->vm_end = addr;
}
@@ -3305,7 +3305,7 @@ int expand_downwards(struct vm_area_struct *vma, unsigned long address)
vm_stat_account(mm, vma->vm_flags, grow);
anon_rmap_tree_pre_update_vma(vma);
vma->vm_start = address;
- vma->vm_pgoff -= grow;
+ vma_sub_pgoff(vma, grow);
/* Overwrite old entry in mtree. */
vma_iter_store_overwrite(&vmi, vma);
anon_rmap_tree_post_update_vma(vma);
diff --git a/mm/vma.h b/mm/vma.h
index 2342516ce00e..47fe35e5307e 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -247,6 +247,18 @@ static inline pgoff_t vmg_end_pgoff(const struct vma_merge_struct *vmg)
return vmg_start_pgoff(vmg) + vmg_pages(vmg);
}
+static inline void vma_add_pgoff(struct vm_area_struct *vma, pgoff_t delta)
+{
+ vma_assert_can_modify(vma);
+ vma->vm_pgoff += delta;
+}
+
+static inline void vma_sub_pgoff(struct vm_area_struct *vma, pgoff_t delta)
+{
+ vma_assert_can_modify(vma);
+ vma->vm_pgoff -= delta;
+}
+
#define VMG_STATE(name, mm_, vmi_, start_, end_, vma_flags_, pgoff_) \
struct vma_merge_struct name = { \
.mm = mm_, \
--
2.55.0
^ permalink raw reply related
* [PATCH v2 24/33] mm/vma: move __install_special_mapping() to vma.c
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
This function is operating on VMAs and rightly belongs in vma.c, where it
can be subject to VMA userland testing and allows us to isolate it from the
rest of mm.
The _install_special_mapping() function will remain in mmap.c as a wrapper,
since this is used by architecture-specific code.
Doing so allows us to isolate more functions in vma.c for the same reasons.
This forms part of work to allow for tracking MAP_PRIVATE file-backed
mappings by their anonymous virtual page offset, as doing so allows us to
isolate and keep code that interacts with this together.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/mmap.c | 38 --------------------------------------
mm/vma.c | 38 ++++++++++++++++++++++++++++++++++++++
mm/vma.h | 5 +++++
3 files changed, 43 insertions(+), 38 deletions(-)
diff --git a/mm/mmap.c b/mm/mmap.c
index 91eaa0c9e7ee..308a43eabd83 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1447,44 +1447,6 @@ static vm_fault_t special_mapping_fault(struct vm_fault *vmf)
return VM_FAULT_SIGBUS;
}
-static struct vm_area_struct *__install_special_mapping(
- struct mm_struct *mm,
- unsigned long addr, unsigned long len,
- vm_flags_t vm_flags, void *priv,
- const struct vm_operations_struct *ops)
-{
- int ret;
- struct vm_area_struct *vma;
-
- vma = vm_area_alloc(mm);
- if (unlikely(vma == NULL))
- return ERR_PTR(-ENOMEM);
-
- vma_set_range(vma, addr, addr + len, 0);
- vm_flags |= mm->def_flags | VM_DONTEXPAND;
- if (pgtable_supports_soft_dirty())
- vm_flags |= VM_SOFTDIRTY;
- vm_flags_init(vma, vm_flags & ~VM_LOCKED_MASK);
- vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
-
- vma->vm_ops = ops;
- vma->vm_private_data = priv;
-
- ret = insert_vm_struct(mm, vma);
- if (ret)
- goto out;
-
- vm_stat_account(mm, vma->vm_flags, len >> PAGE_SHIFT);
-
- perf_event_mmap(vma);
-
- return vma;
-
-out:
- vm_area_free(vma);
- return ERR_PTR(ret);
-}
-
bool vma_is_special_mapping(const struct vm_area_struct *vma,
const struct vm_special_mapping *sm)
{
diff --git a/mm/vma.c b/mm/vma.c
index bdd99ba56b4d..5308aa5a8c91 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -3399,3 +3399,41 @@ __weak unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
{
return vma_kernel_pagesize(vma);
}
+
+struct vm_area_struct *__install_special_mapping(
+ struct mm_struct *mm,
+ unsigned long addr, unsigned long len,
+ vm_flags_t vm_flags, void *priv,
+ const struct vm_operations_struct *ops)
+{
+ int ret;
+ struct vm_area_struct *vma;
+
+ vma = vm_area_alloc(mm);
+ if (unlikely(vma == NULL))
+ return ERR_PTR(-ENOMEM);
+
+ vma_set_range(vma, addr, addr + len, 0);
+ vm_flags |= mm->def_flags | VM_DONTEXPAND;
+ if (pgtable_supports_soft_dirty())
+ vm_flags |= VM_SOFTDIRTY;
+ vm_flags_init(vma, vm_flags & ~VM_LOCKED_MASK);
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+
+ vma->vm_ops = ops;
+ vma->vm_private_data = priv;
+
+ ret = insert_vm_struct(mm, vma);
+ if (ret)
+ goto out;
+
+ vm_stat_account(mm, vma->vm_flags, len >> PAGE_SHIFT);
+
+ perf_event_mmap(vma);
+
+ return vma;
+
+out:
+ vm_area_free(vma);
+ return ERR_PTR(ret);
+}
diff --git a/mm/vma.h b/mm/vma.h
index 47fe35e5307e..14f026bf3be4 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -775,4 +775,9 @@ static inline bool map_deny_write_exec(const vma_flags_t *old,
}
#endif
+struct vm_area_struct *__install_special_mapping(struct mm_struct *mm,
+ unsigned long addr, unsigned long len,
+ vm_flags_t vm_flags, void *priv,
+ const struct vm_operations_struct *ops);
+
#endif /* __MM_VMA_H */
--
2.55.0
^ permalink raw reply related
* [PATCH v2 25/33] mm/vma: make vma_set_range() static, drop insert_vm_struct() decl
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
With __install_special_mapping() moved to vma.c, vma_set_range() can be
made into a static function there and is now completely isolated from the
rest of mm.
While we're here, we can also remove the insert_vm_struct() declaration
from mm.h - the function is implemented in vma.c and already declared in
vma.h, and has no users outside of mm.
Also update the VMA userland tests to reflect this change.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
include/linux/mm.h | 1 -
mm/internal.h | 9 ---------
mm/vma.c | 8 ++++++++
tools/testing/vma/shared.c | 9 ---------
tools/testing/vma/shared.h | 5 -----
5 files changed, 8 insertions(+), 24 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3d69b597b9b1..762313b47301 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -4130,7 +4130,6 @@ void anon_rmap_tree_verify(struct anon_vma_chain *avc);
/* mmap.c */
extern int __vm_enough_memory(const struct mm_struct *mm, long pages, int cap_sys_admin);
-extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
extern void exit_mmap(struct mm_struct *);
bool mmap_read_lock_maybe_expand(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, bool write);
diff --git a/mm/internal.h b/mm/internal.h
index 01a762bcc2b2..2c650d280e90 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1540,15 +1540,6 @@ extern bool mirrored_kernelcore;
bool memblock_has_mirror(void);
void memblock_free_all(void);
-static __always_inline void vma_set_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end,
- pgoff_t pgoff)
-{
- vma->vm_start = start;
- vma->vm_end = end;
- vma->vm_pgoff = pgoff;
-}
-
static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma)
{
/*
diff --git a/mm/vma.c b/mm/vma.c
index 5308aa5a8c91..cc0e449ad0be 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -70,6 +70,14 @@ struct mmap_state {
.state = VMA_MERGE_START, \
}
+static void vma_set_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end, pgoff_t pgoff)
+{
+ vma->vm_start = start;
+ vma->vm_end = end;
+ vma->vm_pgoff = pgoff;
+}
+
/* Was this VMA ever forked from a parent, i.e. maybe contains CoW mappings? */
static bool vma_is_fork_child(struct vm_area_struct *vma)
{
diff --git a/tools/testing/vma/shared.c b/tools/testing/vma/shared.c
index 2565a5aecb80..bea9ea6db02a 100644
--- a/tools/testing/vma/shared.c
+++ b/tools/testing/vma/shared.c
@@ -120,12 +120,3 @@ unsigned long rlimit(unsigned int limit)
{
return (unsigned long)-1;
}
-
-void vma_set_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end,
- pgoff_t pgoff)
-{
- vma->vm_start = start;
- vma->vm_end = end;
- vma->vm_pgoff = pgoff;
-}
diff --git a/tools/testing/vma/shared.h b/tools/testing/vma/shared.h
index 8b9e3b11c3cb..ca4f1238f1c7 100644
--- a/tools/testing/vma/shared.h
+++ b/tools/testing/vma/shared.h
@@ -125,8 +125,3 @@ void __vma_set_dummy_anon_vma(struct vm_area_struct *vma,
/* Provide a simple dummy VMA/anon_vma dummy setup for testing. */
void vma_set_dummy_anon_vma(struct vm_area_struct *vma,
struct anon_vma_chain *avc);
-
-/* Helper function to specify a VMA's range. */
-void vma_set_range(struct vm_area_struct *vma,
- unsigned long start, unsigned long end,
- pgoff_t pgoff);
--
2.55.0
^ permalink raw reply related
* [PATCH v2 26/33] mm/vma: update vma_shrink() to not pass start, pgoff parameters
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
vma_shrink() is only used by relocate_vma_down() to shrink the tail of a
VMA. Therefore neither the start nor the pgoff parameters make any sense.
It seemed we were passing the pgoff parameter solely to satisfy
vma_set_range()'s requirement for pgoff being specified.
Since vma_set_range() is now isolated to vma.c, we can simply introduce
__vma_set_range() which sets only vma->vm_[start, end], and invoke this
instead, removing start and pgoff from vma_shrink() altogether.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 31 +++++++++++++++++--------------
mm/vma.h | 3 +--
mm/vma_exec.c | 2 +-
tools/testing/vma/tests/merge.c | 2 +-
4 files changed, 20 insertions(+), 18 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index cc0e449ad0be..a474920a25b3 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -70,11 +70,17 @@ struct mmap_state {
.state = VMA_MERGE_START, \
}
-static void vma_set_range(struct vm_area_struct *vma, unsigned long start,
- unsigned long end, pgoff_t pgoff)
+static void __vma_set_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
{
vma->vm_start = start;
vma->vm_end = end;
+}
+
+static void vma_set_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end, pgoff_t pgoff)
+{
+ __vma_set_range(vma, start, end);
vma->vm_pgoff = pgoff;
}
@@ -1279,27 +1285,24 @@ int vma_expand(struct vma_merge_struct *vmg)
return -ENOMEM;
}
-/*
- * vma_shrink() - Reduce an existing VMAs memory area
+/**
+ * vma_shrink() - Shrink the end of a VMA
* @vmi: The vma iterator
* @vma: The VMA to modify
- * @start: The new start
* @end: The new end
*
+ * Note that the caller may only shrink the end of the VMA.
+ *
* Returns: 0 on success, -ENOMEM otherwise
*/
int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
- unsigned long start, unsigned long end, pgoff_t pgoff)
+ unsigned long end)
{
struct vma_prepare vp;
- WARN_ON((vma->vm_start != start) && (vma->vm_end != end));
-
- if (vma->vm_start < start)
- vma_iter_config(vmi, vma->vm_start, start);
- else
- vma_iter_config(vmi, end, vma->vm_end);
+ VM_WARN_ON_ONCE(end > vma->vm_end);
+ vma_iter_config(vmi, end, vma->vm_end);
if (vma_iter_prealloc(vmi, NULL))
return -ENOMEM;
@@ -1307,10 +1310,10 @@ int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
init_vma_prep(&vp, vma);
vma_prepare(&vp);
- vma_adjust_trans_huge(vma, start, end, NULL);
+ vma_adjust_trans_huge(vma, vma->vm_start, end, NULL);
vma_iter_clear(vmi);
- vma_set_range(vma, start, end, pgoff);
+ __vma_set_range(vma, vma->vm_start, end);
vma_complete(&vp, vmi, vma->vm_mm);
validate_mm(vma->vm_mm);
return 0;
diff --git a/mm/vma.h b/mm/vma.h
index 14f026bf3be4..40effaa3ebe4 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -297,8 +297,7 @@ void validate_mm(struct mm_struct *mm);
__must_check int vma_expand(struct vma_merge_struct *vmg);
__must_check int vma_shrink(struct vma_iterator *vmi,
- struct vm_area_struct *vma,
- unsigned long start, unsigned long end, pgoff_t pgoff);
+ struct vm_area_struct *vma, unsigned long end);
static inline int vma_iter_store_gfp(struct vma_iterator *vmi,
struct vm_area_struct *vma, gfp_t gfp)
diff --git a/mm/vma_exec.c b/mm/vma_exec.c
index e3644a3042e2..13a05e041195 100644
--- a/mm/vma_exec.c
+++ b/mm/vma_exec.c
@@ -89,7 +89,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift)
vma_prev(&vmi);
/* Shrink the vma to just the new range */
- return vma_shrink(&vmi, vma, new_start, new_end, vma_start_pgoff(vma));
+ return vma_shrink(&vmi, vma, new_end);
}
/*
diff --git a/tools/testing/vma/tests/merge.c b/tools/testing/vma/tests/merge.c
index f8666a755749..e357accc8499 100644
--- a/tools/testing/vma/tests/merge.c
+++ b/tools/testing/vma/tests/merge.c
@@ -227,7 +227,7 @@ static bool test_simple_shrink(void)
ASSERT_FALSE(attach_vma(&mm, vma));
- ASSERT_FALSE(vma_shrink(&vmi, vma, 0, 0x1000, 0));
+ ASSERT_FALSE(vma_shrink(&vmi, vma, 0x1000));
ASSERT_EQ(vma->vm_start, 0);
ASSERT_EQ(vma->vm_end, 0x1000);
--
2.55.0
^ permalink raw reply related
* [PATCH v2 27/33] mm/vma: update vmg_adjust_set_range() to offset pgoff instead
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
We are calculating the pgoff as an offset, since we have vma_add_pgoff()
and vma_sub_pgoff() available, just offset this value directly and use
__vma_set_range() for vma->vm_[start, end] values.
We take care to update the range before offsetting the page offset, so the
adjusted VMA's vm_start and vm_pgoff are mutually consistent at the point
the page offset helpers operate - this matters once vma_set_pgoff() comes
to assert invariants which relate the two.
Doing so lays the foundation for future work which allows for use of
virtual page offsets for MAP_PRIVATE-file backed mappings.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 15 ++++-----------
1 file changed, 4 insertions(+), 11 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index a474920a25b3..0699fa07c40f 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -714,9 +714,6 @@ void validate_mm(struct mm_struct *mm)
*/
static void vmg_adjust_set_range(struct vma_merge_struct *vmg)
{
- struct vm_area_struct *adjust;
- pgoff_t pgoff;
-
if (vmg->__adjust_middle_start) {
/*
* vmg->start vmg->end
@@ -735,8 +732,8 @@ static void vmg_adjust_set_range(struct vma_merge_struct *vmg)
struct vm_area_struct *middle = vmg->middle;
const unsigned long delta = vmg->end - middle->vm_start;
- pgoff = vma_start_pgoff(middle) + (delta >> PAGE_SHIFT);
- adjust = middle;
+ __vma_set_range(middle, vmg->end, middle->vm_end);
+ vma_add_pgoff(middle, delta >> PAGE_SHIFT);
} else if (vmg->__adjust_next_start) {
/*
* Originally:
@@ -764,13 +761,9 @@ static void vmg_adjust_set_range(struct vma_merge_struct *vmg)
struct vm_area_struct *next = vmg->next;
const unsigned long delta = next->vm_start - vmg->end;
- pgoff = vma_start_pgoff(next) - (delta >> PAGE_SHIFT);
- adjust = next;
- } else {
- return;
+ __vma_set_range(next, vmg->end, next->vm_end);
+ vma_sub_pgoff(next, delta >> PAGE_SHIFT);
}
-
- vma_set_range(adjust, vmg->end, adjust->vm_end, pgoff);
}
/*
--
2.55.0
^ permalink raw reply related
* [PATCH v2 28/33] mm/vma: slightly rework the anonymous check in __mmap_new_vma()
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Determine if the VMA is anonymous early on, so we separate the logic which
invokes callbacks from the rest of the logic.
This is in order that a subsequent commit which asserts correct virtual
page offset for anonymous mappings correctly asserts this for new anonymous
mappings.
No functional change intended.
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index 0699fa07c40f..ec64e179d2f9 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -2587,6 +2587,8 @@ static int __mmap_new_file_vma(struct mmap_state *map,
static int __mmap_new_vma(struct mmap_state *map, struct vm_area_struct **vmap,
struct mmap_action *action)
{
+ const bool is_anon = !map->file &&
+ !vma_flags_test(&map->vma_flags, VMA_SHARED_BIT);
struct vma_iterator *vmi = map->vmi;
int error = 0;
struct vm_area_struct *vma;
@@ -2601,6 +2603,10 @@ static int __mmap_new_vma(struct mmap_state *map, struct vm_area_struct **vmap,
return -ENOMEM;
vma_iter_config(vmi, map->addr, map->end);
+
+ if (is_anon)
+ vma_set_anonymous(vma);
+
vma_set_range(vma, map->addr, map->end, map->pgoff);
vma->flags = map->vma_flags;
vma->vm_page_prot = map->page_prot;
@@ -2610,12 +2616,11 @@ static int __mmap_new_vma(struct mmap_state *map, struct vm_area_struct **vmap,
goto free_vma;
}
+ /* Invoke callbacks. */
if (map->file)
error = __mmap_new_file_vma(map, vma);
- else if (vma_flags_test(&map->vma_flags, VMA_SHARED_BIT))
+ else if (!is_anon)
error = shmem_zero_setup(vma);
- else
- vma_set_anonymous(vma);
if (error)
goto free_iter_vma;
--
2.55.0
^ permalink raw reply related
* [PATCH v2 29/33] mm/vma: introduce and use vma_set_pgoff()
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
In order to lay the foundation for work that permits us to track the
virtual page offset of MAP_PRIVATE file-backed mappings, we abstract the
assignment of vma->vm_pgoff to vma_set_pgoff().
We additionally add a lock check here using the newly introduced
vma_assert_can_modify(). This asserts the VMA write lock if the VMA is
attached.
We also assert that, if this is an anonymous VMA and unfaulted, that its
(virtual) page offset is equal to the page offset of the VMA's address.
We must be careful about MAP_PRIVATE-/dev/zero which violates fundamental
assumptions about anonymous memory, so we check for !vma->vm_file after
using vma_is_anonymous() which these mappings satisfy.
Additionally, we only perform the assert if CONFIG_MMU is defined, as nommu
does not set vma->vm_pgoff = addr >> PAGE_SHIFT. This isn't really relevant
to rmap as it has no anon rmap (nor needs it), but we must avoid it
asserting falsely.
All of this logic is kept in assert_sane_pgoff() to keep things clear.
In order to maintain correctness given this assert, we also update
__install_special_mapping() to invoke vma_set_range() after it's set
vma->vm_ops (which determine whether the VMA is anonymous or not).
We do not use vma_set_pgoff() in vm_area_init_from(), as at the point of
forking, we don't necessarily have correct locking state.
Updating vma_set_range() covers most cases, but in addition to this we also
update insert_vm_struct(), compat_set_vma_from_desc() and nommu callers.
We also update vma_add_pgoff() and vma_sub_pgoff() to use vma_set_pgoff().
While we're here, we drop a BUG_ON() and update insert_vm_struct()'s
comment to reflect the fact anonymous mappings can be added here.
Finally, we update the CONFIG_MMU, CONFIG_PER_VMA_LOCK defines in the VMA
userland tests so IS_ENABLED() will work correctly with them.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/nommu.c | 2 +-
mm/vma.c | 14 +++++++-------
mm/vma.h | 35 ++++++++++++++++++++++++++++++++---
tools/testing/vma/vma_internal.h | 4 ++--
4 files changed, 42 insertions(+), 13 deletions(-)
diff --git a/mm/nommu.c b/mm/nommu.c
index 2a0136f6081d..21cbe8b093fc 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1062,7 +1062,7 @@ unsigned long do_mmap(struct file *file,
region->vm_pgoff = pgoff;
vm_flags_init(vma, vm_flags);
- vma->vm_pgoff = pgoff;
+ vma_set_pgoff(vma, pgoff);
if (file) {
region->vm_file = get_file(file);
diff --git a/mm/vma.c b/mm/vma.c
index ec64e179d2f9..7c75dd78edef 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -81,7 +81,7 @@ static void vma_set_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end, pgoff_t pgoff)
{
__vma_set_range(vma, start, end);
- vma->vm_pgoff = pgoff;
+ vma_set_pgoff(vma, pgoff);
}
/* Was this VMA ever forked from a parent, i.e. maybe contains CoW mappings? */
@@ -3347,9 +3347,9 @@ int __vm_munmap(unsigned long start, size_t len, bool unlock)
return ret;
}
-/* Insert vm structure into process list sorted by address
- * and into the inode's i_mmap tree. If vm_file is non-NULL
- * then i_mmap_rwsem is taken here.
+/*
+ * Insert vm structure into process list sorted by address
+ * and into the inode's i_mmap tree if file-backed.
*/
int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
{
@@ -3375,8 +3375,8 @@ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
* Similarly in do_mmap and in do_brk_flags.
*/
if (vma_is_anonymous(vma)) {
- BUG_ON(vma->anon_vma);
- vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
+ WARN_ON_ONCE(vma->anon_vma);
+ vma_set_pgoff(vma, vma->vm_start >> PAGE_SHIFT);
}
if (vma_link(mm, vma)) {
@@ -3422,7 +3422,6 @@ struct vm_area_struct *__install_special_mapping(
if (unlikely(vma == NULL))
return ERR_PTR(-ENOMEM);
- vma_set_range(vma, addr, addr + len, 0);
vm_flags |= mm->def_flags | VM_DONTEXPAND;
if (pgtable_supports_soft_dirty())
vm_flags |= VM_SOFTDIRTY;
@@ -3431,6 +3430,7 @@ struct vm_area_struct *__install_special_mapping(
vma->vm_ops = ops;
vma->vm_private_data = priv;
+ vma_set_range(vma, addr, addr + len, 0);
ret = insert_vm_struct(mm, vma);
if (ret)
diff --git a/mm/vma.h b/mm/vma.h
index 40effaa3ebe4..58f48609ce22 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -247,16 +247,45 @@ static inline pgoff_t vmg_end_pgoff(const struct vma_merge_struct *vmg)
return vmg_start_pgoff(vmg) + vmg_pages(vmg);
}
+static inline void assert_sane_pgoff(struct vm_area_struct *vma, pgoff_t pgoff)
+{
+ /* nommu doesn't set a virtual pgoff for anon VMAs. */
+ if (!IS_ENABLED(CONFIG_MMU))
+ return;
+ /*
+ * File-backed VMAs have arbitrary page offset (either page offset into
+ * file or for pfnmap the PFN of the start of the range or drivers may
+ * set arbitrary page offset).
+ */
+ if (!vma_is_anonymous(vma))
+ return;
+ /* MAP_PRIVATE-/dev/zero is anon, non-NULL vm_file, but has file pgoff. */
+ if (vma->vm_file)
+ return;
+ /* If faulted in, could have been remapped. */
+ if (vma->anon_vma)
+ return;
+ /* OK this is really an anon VMA - expect virtual page offset. */
+ VM_WARN_ON_ONCE(pgoff != vma->vm_start >> PAGE_SHIFT);
+}
+
+static inline void vma_set_pgoff(struct vm_area_struct *vma, pgoff_t pgoff)
+{
+ vma_assert_can_modify(vma);
+ assert_sane_pgoff(vma, pgoff);
+ vma->vm_pgoff = pgoff;
+}
+
static inline void vma_add_pgoff(struct vm_area_struct *vma, pgoff_t delta)
{
vma_assert_can_modify(vma);
- vma->vm_pgoff += delta;
+ vma_set_pgoff(vma, vma_start_pgoff(vma) + delta);
}
static inline void vma_sub_pgoff(struct vm_area_struct *vma, pgoff_t delta)
{
vma_assert_can_modify(vma);
- vma->vm_pgoff -= delta;
+ vma_set_pgoff(vma, vma_start_pgoff(vma) - delta);
}
#define VMG_STATE(name, mm_, vmi_, start_, end_, vma_flags_, pgoff_) \
@@ -331,7 +360,7 @@ static inline void compat_set_vma_from_desc(struct vm_area_struct *vma,
*/
/* Mutable fields. Populated with initial state. */
- vma->vm_pgoff = desc->pgoff;
+ vma_set_pgoff(vma, desc->pgoff);
if (desc->vm_file != vma->vm_file)
vma_set_file(vma, desc->vm_file);
vma->flags = desc->vma_flags;
diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h
index e12ab2c80f95..4f6c5666ac07 100644
--- a/tools/testing/vma/vma_internal.h
+++ b/tools/testing/vma/vma_internal.h
@@ -14,8 +14,8 @@
#include <stdlib.h>
-#define CONFIG_MMU
-#define CONFIG_PER_VMA_LOCK
+#define CONFIG_MMU 1
+#define CONFIG_PER_VMA_LOCK 1
#ifdef __CONCAT
#undef __CONCAT
--
2.55.0
^ permalink raw reply related
* [PATCH v2 30/33] mm/vma: correct incorrect vma.h inclusion
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
The only files which should be including vma.h are the implementation files
for the core VMA logic - vma.c, vma_init.c, and vma_exec.c.
This is in order to allow for userland testing of core VMA logic. In this
cases, vma_internal.h and vma.h are included, providing both the
dependencies upon which the core VMA logic requires and its declarations.
Userland testable VMA logic is achieved by having separate vma_internal.h
implementations for userland and kernel.
Callers other than the core VMA implementation should include internal.h
instead. This header does not need to include vma_internal.h as it only
contains the vma.h declarations, for which the includes already present
suffice.
Update code to reflect this, update comments to reflect the fact there are
3 VMA implementation files and document things more clearly.
While we're here, slightly improve the language of the comment describing
vma_exec.c.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/mmu_notifier.c | 2 +-
mm/nommu.c | 1 -
mm/vma.c | 4 ++++
mm/vma.h | 9 ++++++++-
mm/vma_exec.c | 8 ++++++--
mm/vma_init.c | 4 ++++
mm/vma_internal.h | 4 ++--
7 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/mm/mmu_notifier.c b/mm/mmu_notifier.c
index 245b74f39f91..df69ba6e797f 100644
--- a/mm/mmu_notifier.c
+++ b/mm/mmu_notifier.c
@@ -19,7 +19,7 @@
#include <linux/sched/mm.h>
#include <linux/slab.h>
-#include "vma.h"
+#include "internal.h"
/* global SRCU for all MMs */
DEFINE_STATIC_SRCU(srcu);
diff --git a/mm/nommu.c b/mm/nommu.c
index 21cbe8b093fc..adc0b0ca906b 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -41,7 +41,6 @@
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include "internal.h"
-#include "vma.h"
unsigned long highest_memmap_pfn;
int heap_stack_gap = 0;
diff --git a/mm/vma.c b/mm/vma.c
index 7c75dd78edef..737f0d692e6b 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -4,6 +4,10 @@
* VMA-specific functions.
*/
+/*
+ * To allow for userland testing we place internal dependencies in
+ * vma_internal.h and external VMA API declarations in vma.h.
+ */
#include "vma_internal.h"
#include "vma.h"
diff --git a/mm/vma.h b/mm/vma.h
index 58f48609ce22..adb7a0ba1192 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -2,7 +2,14 @@
/*
* vma.h
*
- * Core VMA manipulation API implemented in vma.c.
+ * Core VMA manipulation API implemented in vma.c, vma_init.c and vma_exec.c.
+ *
+ * Note that, in order for VMA logic to be userland testable, this header
+ * intentionally includes no dependencies.
+ *
+ * This is specifically scoped to mm-only. Users of this functionality (other
+ * than the core VMA implementation itself) should not include this header
+ * directly, but rather include internal.h.
*/
#ifndef __MM_VMA_H
#define __MM_VMA_H
diff --git a/mm/vma_exec.c b/mm/vma_exec.c
index 13a05e041195..ef1fa2b161f3 100644
--- a/mm/vma_exec.c
+++ b/mm/vma_exec.c
@@ -1,10 +1,14 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * Functions explicitly implemented for exec functionality which however are
- * explicitly VMA-only logic.
+ * Functions provided for exec functionality which however are
+ * specifically VMA-only logic.
*/
+/*
+ * To allow for userland testing we place internal dependencies in
+ * vma_internal.h and external VMA API declarations in vma.h.
+ */
#include "vma_internal.h"
#include "vma.h"
diff --git a/mm/vma_init.c b/mm/vma_init.c
index a459669a1654..715feee283f0 100644
--- a/mm/vma_init.c
+++ b/mm/vma_init.c
@@ -5,6 +5,10 @@
* between CONFIG_MMU and non-CONFIG_MMU kernel configurations.
*/
+/*
+ * To allow for userland testing we place internal dependencies in
+ * vma_internal.h and external VMA API declarations in vma.h.
+ */
#include "vma_internal.h"
#include "vma.h"
diff --git a/mm/vma_internal.h b/mm/vma_internal.h
index 2da6d224c1a8..4d300e7bbaf4 100644
--- a/mm/vma_internal.h
+++ b/mm/vma_internal.h
@@ -2,8 +2,8 @@
/*
* vma_internal.h
*
- * Headers required by vma.c, which can be substituted accordingly when testing
- * VMA functionality.
+ * Headers required by vma.c, vma_init.c and vma_exec.c, which can be
+ * substituted accordingly when testing VMA functionality.
*/
#ifndef __MM_VMA_INTERNAL_H
--
2.55.0
^ permalink raw reply related
* [PATCH v2 31/33] mm/vma: use guard clauses in can_vma_merge_[before, after]()
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Rather than combining a bunch of conditionals in a single expression,
simplify by inverting the mergeability requirements into guard clauses.
that is - instead of checking what must be true for the conditions to be
met, instead check the inverse of the requirements and return false if any
are true, defaulting to true.
No functional change intended.
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
mm/vma.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)
diff --git a/mm/vma.c b/mm/vma.c
index 737f0d692e6b..9d556d33b24b 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -215,13 +215,13 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
*/
static bool can_vma_merge_before(struct vma_merge_struct *vmg)
{
- if (is_mergeable_vma(vmg, /* merge_next = */ true) &&
- is_mergeable_anon_vma(vmg, /* merge_next = */ true)) {
- if (vmg_end_pgoff(vmg) == vma_start_pgoff(vmg->next))
- return true;
- }
-
- return false;
+ if (!is_mergeable_vma(vmg, /* merge_next = */ true))
+ return false;
+ if (!is_mergeable_anon_vma(vmg, /* merge_next = */ true))
+ return false;
+ if (vmg_end_pgoff(vmg) != vma_start_pgoff(vmg->next))
+ return false;
+ return true;
}
/*
@@ -235,12 +235,13 @@ static bool can_vma_merge_before(struct vma_merge_struct *vmg)
*/
static bool can_vma_merge_after(struct vma_merge_struct *vmg)
{
- if (is_mergeable_vma(vmg, /* merge_next = */ false) &&
- is_mergeable_anon_vma(vmg, /* merge_next = */ false)) {
- if (vma_end_pgoff(vmg->prev) == vmg_start_pgoff(vmg))
- return true;
- }
- return false;
+ if (!is_mergeable_vma(vmg, /* merge_next = */ false))
+ return false;
+ if (!is_mergeable_anon_vma(vmg, /* merge_next = */ false))
+ return false;
+ if (vma_end_pgoff(vmg->prev) != vmg_start_pgoff(vmg))
+ return false;
+ return true;
}
static void __vma_link_file(struct vm_area_struct *vma,
--
2.55.0
^ permalink raw reply related
* [PATCH v2 32/33] tools/testing/vma: default VMA, mm flag bits to 64-bit
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
With all of the sanitisers turned on, setting the VMA and mm flag bits
depth to 128 by default results in overly long build times.
Reduce this to 64 - we can always manipulate these later for testing of
larger bitmaps as needed.
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
tools/testing/vma/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/vma/Makefile b/tools/testing/vma/Makefile
index e72b45dedda5..ef6cc558afe1 100644
--- a/tools/testing/vma/Makefile
+++ b/tools/testing/vma/Makefile
@@ -10,7 +10,7 @@ OFILES = $(SHARED_OFILES) main.o shared.o maple-shim.o
TARGETS = vma
# These can be varied to test different sizes.
-CFLAGS += -DNUM_VMA_FLAG_BITS=128 -DNUM_MM_FLAG_BITS=128
+CFLAGS += -DNUM_VMA_FLAG_BITS=64 -DNUM_MM_FLAG_BITS=64
main.o: main.c shared.c shared.h vma_internal.h tests/merge.c tests/mmap.c tests/vma.c ../../../mm/vma.c ../../../mm/vma_init.c ../../../mm/vma_exec.c ../../../mm/vma.h include/custom.h include/dup.h include/stubs.h
--
2.55.0
^ permalink raw reply related
* [PATCH v2 33/33] tools/testing/vma: output compared expression on ASSERT_[EQ, NE]()
From: Lorenzo Stoakes @ 2026-07-10 20:17 UTC (permalink / raw)
To: Andrew Morton, David Hildenbrand, Liam R. Howlett,
Vlastimil Babka, Mike Rapoport, Suren Baghdasaryan, Michal Hocko,
Rik van Riel, Harry Yoo, Jann Horn, Lance Yang, Pedro Falcato,
Russell King, Dinh Nguyen, Simon Schuster, James E.J. Bottomley,
Helge Deller, Alexander Viro, Christian Brauner, Jan Kara,
Dan Williams, Matthew Wilcox, Muchun Song, Oscar Salvador,
Masami Hiramatsu, Oleg Nesterov, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Namhyung Kim, Mark Rutland,
Alexander Shishkin, Jiri Olsa, Ian Rogers, Adrian Hunter,
James Clark, Zi Yan, Baolin Wang, Nico Pache, Ryan Roberts,
Dev Jain, Barry Song, Miaohe Lin, Naoya Horiguchi, Xu Xin,
Chengming Zhou, SJ Park, Matthew Brost, Joshua Hahn, Rakie Kim,
Byungchul Park, Gregory Price, Ying Huang, Alistair Popple,
Hugh Dickins, Peter Xu, Kees Cook, Marek Szyprowski, Robin Murphy,
Andrey Konovalov, Alexander Potapenko, Dmitry Vyukov,
Steven Rostedt, Mathieu Desnoyers, Jarkko Sakkinen, Dave Hansen,
Thomas Gleixner, Borislav Petkov, x86, H. Peter Anvin, Ian Abbott,
H Hartley Sweeten, Lucas Stach, Christian Gmeiner, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Abhinav Kumar,
Jessica Zhang, Sean Paul, Marijn Suijten, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Matthew Auld, Jason Gunthorpe,
Yishai Hadas, Shameer Kolothum, Kevin Tian, Ankit Agrawal,
Alex Williamson, Paolo Bonzini, Shakeel Butt, Usama Arif
Cc: Lorenzo Stoakes, linux-mm, linux-kernel, linux-arm-kernel,
linux-parisc, linux-fsdevel, nvdimm, linux-perf-users,
linux-trace-kernel, damon, iommu, kasan-dev, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
Russell King
In-Reply-To: <20260710-b4-pre-scalable-cow-v2-0-2a5aa403d977@kernel.org>
Update the macros to output the compared values at hex for easier debugging
when test asserts fail.
We have to be careful not to re-evaluate expressions as they may have
side-effects. So update the code to take local copies and use these for
both the test and the debug output.
Also remove unused IS_SET() macro.
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
---
tools/testing/vma/shared.h | 38 ++++++++++++++++++++++++++------------
1 file changed, 26 insertions(+), 12 deletions(-)
diff --git a/tools/testing/vma/shared.h b/tools/testing/vma/shared.h
index ca4f1238f1c7..97cd7a679dc1 100644
--- a/tools/testing/vma/shared.h
+++ b/tools/testing/vma/shared.h
@@ -21,19 +21,35 @@
} \
} while (0)
-#define ASSERT_TRUE(_expr) \
- do { \
- if (!(_expr)) { \
- fprintf(stderr, \
- "Assert FAILED at %s:%d:%s(): %s is FALSE.\n", \
- __FILE__, __LINE__, __FUNCTION__, #_expr); \
- return false; \
- } \
+#define __ASSERT_TRUE(_expr, _fmt, ...) \
+ do { \
+ if (!(_expr)) { \
+ fprintf(stderr, \
+ "Assert FAILED at %s:%d:%s(): %s is FALSE" \
+ _fmt ".\n", \
+ __FILE__, __LINE__, __FUNCTION__, #_expr \
+ __VA_OPT__(,) __VA_ARGS__); \
+ return false; \
+ } \
} while (0)
+#define __TO_SCALAR(x) ((unsigned long long)(uintptr_t)(x))
+
+#define ASSERT_TRUE(_expr) __ASSERT_TRUE(_expr, "")
#define ASSERT_FALSE(_expr) ASSERT_TRUE(!(_expr))
-#define ASSERT_EQ(_val1, _val2) ASSERT_TRUE((_val1) == (_val2))
-#define ASSERT_NE(_val1, _val2) ASSERT_TRUE((_val1) != (_val2))
+#define ASSERT_EQ(_val1, _val2) do { \
+ __typeof__(_val1) __val1 = (_val1); \
+ __typeof__(_val2) __val2 = (_val2); \
+ __ASSERT_TRUE(__val1 == __val2, " (0x%llx != 0x%llx)", \
+ __TO_SCALAR(__val1), __TO_SCALAR(__val2)); \
+ } while (0)
+
+#define ASSERT_NE(_val1, _val2) do { \
+ __typeof__(_val1) __val1 = (_val1); \
+ __typeof__(_val2) __val2 = (_val2); \
+ __ASSERT_TRUE(__val1 != __val2, " (0x%llx == 0x%llx)", \
+ __TO_SCALAR(__val1), __TO_SCALAR(__val2)); \
+ } while (0)
#define ASSERT_FLAGS_SAME_MASK(_flags, _flags_other) \
ASSERT_TRUE(vma_flags_same_mask((_flags), (_flags_other)))
@@ -53,8 +69,6 @@
#define ASSERT_FLAGS_NONEMPTY(_flags) \
ASSERT_FALSE(vma_flags_empty(_flags))
-#define IS_SET(_val, _flags) ((_val & _flags) == _flags)
-
extern bool fail_prealloc;
/* Override vma_iter_prealloc() so we can choose to fail it. */
--
2.55.0
^ permalink raw reply related
* Re: [PATCH 30/30] tools/testing/vma: output compared expression on ASSERT_[EQ, NE]()
From: Gregory Price @ 2026-07-10 20:48 UTC (permalink / raw)
To: Lorenzo Stoakes
Cc: Andrew Morton, Russell King, Dinh Nguyen, Simon Schuster,
James E . J . Bottomley, Helge Deller, Jarkko Sakkinen,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, x86,
Ian Abbott, H Hartley Sweeten, Lucas Stach, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Ankit Agrawal, Alex Williamson,
Alexander Viro, Christian Brauner, Dan Williams, Muchun Song,
Oscar Salvador, David Hildenbrand, Suren Baghdasaryan,
Liam R . Howlett, Matthew Wilcox, Marek Szyprowski,
Peter Zijlstra, Arnaldo Carvalho de Melo, Namhyung Kim,
Masami Hiramatsu, Oleg Nesterov, Steven Rostedt, SeongJae Park,
Miaohe Lin, Hugh Dickins, Mike Rapoport, Kees Cook, Paolo Bonzini,
linux-kernel, linux-arm-kernel, linux-parisc, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
linux-fsdevel, nvdimm, linux-mm, iommu, linux-perf-users,
linux-trace-kernel, kasan-dev, damon, Pedro Falcato, Rik van Riel,
Harry Yoo, Jann Horn
In-Reply-To: <432444fa4c12ae1c4047550e2b205d3e9bab458f.1782735110.git.ljs@kernel.org>
On Mon, Jun 29, 2026 at 01:23:41PM +0100, Lorenzo Stoakes wrote:
> -#define ASSERT_TRUE(_expr) \
> - do { \
> - if (!(_expr)) { \
> - fprintf(stderr, \
> - "Assert FAILED at %s:%d:%s(): %s is FALSE.\n", \
> - __FILE__, __LINE__, __FUNCTION__, #_expr); \
> - return false; \
> - } \
> +#define __ASSERT_TRUE(_expr, _fmt, ...) \
> + do { \
> + if (!(_expr)) { \
> + fprintf(stderr, \
> + "Assert FAILED at %s:%d:%s(): %s is FALSE" \
> + _fmt ".\n", \
> + __FILE__, __LINE__, __FUNCTION__, #_expr \
> + __VA_OPT__(,) __VA_ARGS__); \
> + return false; \
> + } \
> } while (0)
>
> +#define __TO_SCALAR(x) ((unsigned long long)(uintptr_t)(x))
> +
> +#define ASSERT_TRUE(_expr) __ASSERT_TRUE(_expr, "")
Mmmmm... macro madness.... I don't think this is what you want.
I think you end up double-running the expression in the failure branch.
ASSERT_EQ(cleanup_mm(&mm, &vmi), 2)
run through the preprocessor expands to:
do {
if (!( (cleanup_mm(&mm, &vmi)) == (2) )) {
**** first run ****
fprintf(stderr,
"Assert FAILED at %s:%d:%s(): %s is FALSE" " (0x%llx != 0x%llx)" ".\n",
"merge.c", 645, __FUNCTION__,
"(cleanup_mm(&mm, &vmi)) == (2)",
((unsigned long long)(uintptr_t)(cleanup_mm(&mm, &vmi))),
**** second run ****
((unsigned long long)(uintptr_t)(2)));
return false;
}
} while (0);
A bunch of existing ASSERT callers mutate state, so there's no guarantee
the printed value matches teh actual test value.
I think you want something like:
#define ASSERT_EQ(_val1, _val2) do { \
__auto_type _v1 = (_val1); \
__auto_type _v2 = (_val2); \
__ASSERT_TRUE(_v1 == _v2, " (0x%llx != 0x%llx)", \
__TO_SCALAR(_v1), __TO_SCALAR(_v2)); \
} while (0)
which expands to:
do {
__auto_type _v1 = (cleanup_mm(&mm, &vmi));
__auto_type _v2 = (2);
do {
if (!(_v1 == _v2)) {
fprintf(stderr, "...FALSE (0x%llx != 0x%llx).\n",
"merge.c", 645, __FUNCTION__, "_v1 == _v2",
((unsigned long long)(uintptr_t)(_v1)),
((unsigned long long)(uintptr_t)(_v2)));
return false;
}
} while (0);
} while (0);
~Gregory
^ permalink raw reply
* Re: [PATCH 27/30] mm/vma: correct incorrect vma.h inclusion
From: Gregory Price @ 2026-07-10 21:03 UTC (permalink / raw)
To: Lorenzo Stoakes
Cc: Andrew Morton, Russell King, Dinh Nguyen, Simon Schuster,
James E . J . Bottomley, Helge Deller, Jarkko Sakkinen,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, x86,
Ian Abbott, H Hartley Sweeten, Lucas Stach, David Airlie,
Simona Vetter, Patrik Jakobsson, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, Rob Clark, Dmitry Baryshkov, Tomi Valkeinen,
Thierry Reding, Mikko Perttunen, Jonathan Hunter,
Christian Koenig, Huang Rui, Ankit Agrawal, Alex Williamson,
Alexander Viro, Christian Brauner, Dan Williams, Muchun Song,
Oscar Salvador, David Hildenbrand, Suren Baghdasaryan,
Liam R . Howlett, Matthew Wilcox, Marek Szyprowski,
Peter Zijlstra, Arnaldo Carvalho de Melo, Namhyung Kim,
Masami Hiramatsu, Oleg Nesterov, Steven Rostedt, SeongJae Park,
Miaohe Lin, Hugh Dickins, Mike Rapoport, Kees Cook, Paolo Bonzini,
linux-kernel, linux-arm-kernel, linux-parisc, linux-sgx, etnaviv,
dri-devel, linux-arm-msm, freedreno, linux-tegra, kvm,
linux-fsdevel, nvdimm, linux-mm, iommu, linux-perf-users,
linux-trace-kernel, kasan-dev, damon, Pedro Falcato, Rik van Riel,
Harry Yoo, Jann Horn
In-Reply-To: <alFJUfaGHVnKd-Nb@lucifer>
On Fri, Jul 10, 2026 at 08:35:43PM +0100, Lorenzo Stoakes wrote:
> >
> > Do you actually need 3 copies of this comment or just one copy in
> > vma_internal.h?
>
> I'd rather have it at a glance, it's a bit silly but C headers are silly :P
>
> BTW you're kinda racing against time here as I'm on the verge of sending v2
> :P
:[ i don't refresh my inbox when i get hyperfocused and now i am sad
^ permalink raw reply
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