* [PATCH v3 5/7] io_uring: rsrc: use FOLL_SAME_FILE on pin_user_pages()
[not found] <[email protected]>
@ 2023-04-15 12:09 ` Lorenzo Stoakes
2023-04-15 12:09 ` [PATCH v3 6/7] mm/gup: remove vmas parameter from pin_user_pages() Lorenzo Stoakes
1 sibling, 0 replies; 4+ messages in thread
From: Lorenzo Stoakes @ 2023-04-15 12:09 UTC (permalink / raw)
To: linux-mm, linux-kernel, Andrew Morton
Cc: Matthew Wilcox, David Hildenbrand, Jens Axboe, Pavel Begunkov,
io-uring, Lorenzo Stoakes
Commit edd478269640 ("io_uring/rsrc: disallow multi-source reg buffers")
prevents io_pin_pages() from pinning pages spanning multiple VMAs with
permitted characteristics (anon/huge), requiring that all VMAs share the
same vm_file.
The newly introduced FOLL_SAME_FILE flag permits this to be expressed as a
GUP flag rather than having to retrieve VMAs to perform the check.
We then only need to perform a VMA lookup for the first VMA to assert the
anon/hugepage requirement as we know the rest of the VMAs will possess the
same characteristics.
Doing this eliminates the one instance of vmas being used by
pin_user_pages().
Signed-off-by: Lorenzo Stoakes <[email protected]>
Suggested-by: Matthew Wilcox (Oracle) <[email protected]>
---
io_uring/rsrc.c | 40 ++++++++++++++++++----------------------
1 file changed, 18 insertions(+), 22 deletions(-)
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index 7a43aed8e395..56de4d7bfc2b 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -1141,9 +1141,8 @@ static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages)
{
unsigned long start, end, nr_pages;
- struct vm_area_struct **vmas = NULL;
struct page **pages = NULL;
- int i, pret, ret = -ENOMEM;
+ int pret, ret = -ENOMEM;
end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
start = ubuf >> PAGE_SHIFT;
@@ -1153,31 +1152,29 @@ struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages)
if (!pages)
goto done;
- vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
- GFP_KERNEL);
- if (!vmas)
- goto done;
-
ret = 0;
mmap_read_lock(current->mm);
- pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
- pages, vmas);
+ pret = pin_user_pages(ubuf, nr_pages,
+ FOLL_WRITE | FOLL_LONGTERM | FOLL_SAME_FILE,
+ pages, NULL);
if (pret == nr_pages) {
- struct file *file = vmas[0]->vm_file;
+ /*
+ * lookup the first VMA, we require that all VMAs in range
+ * maintain the same file characteristics, as enforced by
+ * FOLL_SAME_FILE
+ */
+ struct vm_area_struct *vma = vma_lookup(current->mm, ubuf);
+ struct file *file;
- /* don't support file backed memory */
- for (i = 0; i < nr_pages; i++) {
- if (vmas[i]->vm_file != file) {
- ret = -EINVAL;
- break;
- }
- if (!file)
- continue;
- if (!vma_is_shmem(vmas[i]) && !is_file_hugepages(file)) {
+ if (WARN_ON_ONCE(!vma)) {
+ ret = -EINVAL;
+ } else {
+ /* don't support file backed memory */
+ file = vma->vm_file;
+ if (file && !vma_is_shmem(vma) && !is_file_hugepages(file))
ret = -EOPNOTSUPP;
- break;
- }
}
+
*npages = nr_pages;
} else {
ret = pret < 0 ? pret : -EFAULT;
@@ -1194,7 +1191,6 @@ struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages)
}
ret = 0;
done:
- kvfree(vmas);
if (ret < 0) {
kvfree(pages);
pages = ERR_PTR(ret);
--
2.40.0
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH v3 6/7] mm/gup: remove vmas parameter from pin_user_pages()
[not found] <[email protected]>
2023-04-15 12:09 ` [PATCH v3 5/7] io_uring: rsrc: use FOLL_SAME_FILE on pin_user_pages() Lorenzo Stoakes
@ 2023-04-15 12:09 ` Lorenzo Stoakes
2023-04-17 11:14 ` David Hildenbrand
2023-04-17 11:59 ` Dennis Dalessandro
1 sibling, 2 replies; 4+ messages in thread
From: Lorenzo Stoakes @ 2023-04-15 12:09 UTC (permalink / raw)
To: linux-mm, linux-kernel, Andrew Morton
Cc: Matthew Wilcox, David Hildenbrand, Michael Ellerman,
Nicholas Piggin, Christophe Leroy, Dennis Dalessandro,
Jason Gunthorpe, Leon Romanovsky, Christian Benvenuti,
Nelson Escobar, Bernard Metzler, Mauro Carvalho Chehab,
Michael S . Tsirkin, Jason Wang, Jens Axboe, Pavel Begunkov,
Bjorn Topel, Magnus Karlsson, Maciej Fijalkowski, Jonathan Lemon,
David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Alexei Starovoitov, Daniel Borkmann, Jesper Dangaard Brouer,
John Fastabend, linuxppc-dev, linux-rdma, linux-media,
virtualization, kvm, netdev, io-uring, bpf, Lorenzo Stoakes
After the introduction of FOLL_SAME_FILE we no longer require vmas for any
invocation of pin_user_pages(), so eliminate this parameter from the
function and all callers.
This clears the way to removing the vmas parameter from GUP altogether.
Signed-off-by: Lorenzo Stoakes <[email protected]>
---
arch/powerpc/mm/book3s64/iommu_api.c | 2 +-
drivers/infiniband/hw/qib/qib_user_pages.c | 2 +-
drivers/infiniband/hw/usnic/usnic_uiom.c | 2 +-
drivers/infiniband/sw/siw/siw_mem.c | 2 +-
drivers/media/v4l2-core/videobuf-dma-sg.c | 2 +-
drivers/vdpa/vdpa_user/vduse_dev.c | 2 +-
drivers/vhost/vdpa.c | 2 +-
include/linux/mm.h | 3 +--
io_uring/rsrc.c | 2 +-
mm/gup.c | 9 +++------
mm/gup_test.c | 9 ++++-----
net/xdp/xdp_umem.c | 2 +-
12 files changed, 17 insertions(+), 22 deletions(-)
diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s64/iommu_api.c
index 81d7185e2ae8..d19fb1f3007d 100644
--- a/arch/powerpc/mm/book3s64/iommu_api.c
+++ b/arch/powerpc/mm/book3s64/iommu_api.c
@@ -105,7 +105,7 @@ static long mm_iommu_do_alloc(struct mm_struct *mm, unsigned long ua,
ret = pin_user_pages(ua + (entry << PAGE_SHIFT), n,
FOLL_WRITE | FOLL_LONGTERM,
- mem->hpages + entry, NULL);
+ mem->hpages + entry);
if (ret == n) {
pinned += n;
continue;
diff --git a/drivers/infiniband/hw/qib/qib_user_pages.c b/drivers/infiniband/hw/qib/qib_user_pages.c
index f693bc753b6b..1bb7507325bc 100644
--- a/drivers/infiniband/hw/qib/qib_user_pages.c
+++ b/drivers/infiniband/hw/qib/qib_user_pages.c
@@ -111,7 +111,7 @@ int qib_get_user_pages(unsigned long start_page, size_t num_pages,
ret = pin_user_pages(start_page + got * PAGE_SIZE,
num_pages - got,
FOLL_LONGTERM | FOLL_WRITE,
- p + got, NULL);
+ p + got);
if (ret < 0) {
mmap_read_unlock(current->mm);
goto bail_release;
diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c
index 2a5cac2658ec..84e0f41e7dfa 100644
--- a/drivers/infiniband/hw/usnic/usnic_uiom.c
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.c
@@ -140,7 +140,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
ret = pin_user_pages(cur_base,
min_t(unsigned long, npages,
PAGE_SIZE / sizeof(struct page *)),
- gup_flags, page_list, NULL);
+ gup_flags, page_list);
if (ret < 0)
goto out;
diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c
index f51ab2ccf151..e6e25f15567d 100644
--- a/drivers/infiniband/sw/siw/siw_mem.c
+++ b/drivers/infiniband/sw/siw/siw_mem.c
@@ -422,7 +422,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable)
umem->page_chunk[i].plist = plist;
while (nents) {
rv = pin_user_pages(first_page_va, nents, foll_flags,
- plist, NULL);
+ plist);
if (rv < 0)
goto out_sem_up;
diff --git a/drivers/media/v4l2-core/videobuf-dma-sg.c b/drivers/media/v4l2-core/videobuf-dma-sg.c
index 53001532e8e3..405b89ea1054 100644
--- a/drivers/media/v4l2-core/videobuf-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf-dma-sg.c
@@ -180,7 +180,7 @@ static int videobuf_dma_init_user_locked(struct videobuf_dmabuf *dma,
data, size, dma->nr_pages);
err = pin_user_pages(data & PAGE_MASK, dma->nr_pages, gup_flags,
- dma->pages, NULL);
+ dma->pages);
if (err != dma->nr_pages) {
dma->nr_pages = (err >= 0) ? err : 0;
diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index 0c3b48616a9f..1f80254604f0 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -995,7 +995,7 @@ static int vduse_dev_reg_umem(struct vduse_dev *dev,
goto out;
pinned = pin_user_pages(uaddr, npages, FOLL_LONGTERM | FOLL_WRITE,
- page_list, NULL);
+ page_list);
if (pinned != npages) {
ret = pinned < 0 ? pinned : -ENOMEM;
goto out;
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 7be9d9d8f01c..4317128c1c62 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -952,7 +952,7 @@ static int vhost_vdpa_pa_map(struct vhost_vdpa *v,
while (npages) {
sz2pin = min_t(unsigned long, npages, list_size);
pinned = pin_user_pages(cur_base, sz2pin,
- gup_flags, page_list, NULL);
+ gup_flags, page_list);
if (sz2pin != pinned) {
if (pinned < 0) {
ret = pinned;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 1bfe73a2b6d3..363e3d0d46f4 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2382,8 +2382,7 @@ long pin_user_pages_remote(struct mm_struct *mm,
long get_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages);
long pin_user_pages(unsigned long start, unsigned long nr_pages,
- unsigned int gup_flags, struct page **pages,
- struct vm_area_struct **vmas);
+ unsigned int gup_flags, struct page **pages);
long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
struct page **pages, unsigned int gup_flags);
long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index 56de4d7bfc2b..bd45681de660 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -1156,7 +1156,7 @@ struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages)
mmap_read_lock(current->mm);
pret = pin_user_pages(ubuf, nr_pages,
FOLL_WRITE | FOLL_LONGTERM | FOLL_SAME_FILE,
- pages, NULL);
+ pages);
if (pret == nr_pages) {
/*
* lookup the first VMA, we require that all VMAs in range
diff --git a/mm/gup.c b/mm/gup.c
index 3954ce499a4a..714970ef3b30 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -3132,8 +3132,6 @@ EXPORT_SYMBOL(pin_user_pages_remote);
* @gup_flags: flags modifying lookup behaviour
* @pages: array that receives pointers to the pages pinned.
* Should be at least nr_pages long.
- * @vmas: array of pointers to vmas corresponding to each page.
- * Or NULL if the caller does not require them.
*
* Nearly the same as get_user_pages(), except that FOLL_TOUCH is not set, and
* FOLL_PIN is set.
@@ -3142,15 +3140,14 @@ EXPORT_SYMBOL(pin_user_pages_remote);
* see Documentation/core-api/pin_user_pages.rst for details.
*/
long pin_user_pages(unsigned long start, unsigned long nr_pages,
- unsigned int gup_flags, struct page **pages,
- struct vm_area_struct **vmas)
+ unsigned int gup_flags, struct page **pages)
{
int locked = 1;
- if (!is_valid_gup_args(pages, vmas, NULL, &gup_flags, FOLL_PIN))
+ if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_PIN))
return 0;
return __gup_longterm_locked(current->mm, start, nr_pages,
- pages, vmas, &locked, gup_flags);
+ pages, NULL, &locked, gup_flags);
}
EXPORT_SYMBOL(pin_user_pages);
diff --git a/mm/gup_test.c b/mm/gup_test.c
index 9ba8ea23f84e..1668ce0e0783 100644
--- a/mm/gup_test.c
+++ b/mm/gup_test.c
@@ -146,18 +146,17 @@ static int __gup_test_ioctl(unsigned int cmd,
pages + i);
break;
case PIN_BASIC_TEST:
- nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i,
- NULL);
+ nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i);
break;
case PIN_LONGTERM_BENCHMARK:
nr = pin_user_pages(addr, nr,
gup->gup_flags | FOLL_LONGTERM,
- pages + i, NULL);
+ pages + i);
break;
case DUMP_USER_PAGES_TEST:
if (gup->test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN)
nr = pin_user_pages(addr, nr, gup->gup_flags,
- pages + i, NULL);
+ pages + i);
else
nr = get_user_pages(addr, nr, gup->gup_flags,
pages + i);
@@ -270,7 +269,7 @@ static inline int pin_longterm_test_start(unsigned long arg)
gup_flags, pages);
else
cur_pages = pin_user_pages(addr, remaining_pages,
- gup_flags, pages, NULL);
+ gup_flags, pages);
if (cur_pages < 0) {
pin_longterm_test_stop();
ret = cur_pages;
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index 02207e852d79..06cead2b8e34 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -103,7 +103,7 @@ static int xdp_umem_pin_pages(struct xdp_umem *umem, unsigned long address)
mmap_read_lock(current->mm);
npgs = pin_user_pages(address, umem->npgs,
- gup_flags | FOLL_LONGTERM, &umem->pgs[0], NULL);
+ gup_flags | FOLL_LONGTERM, &umem->pgs[0]);
mmap_read_unlock(current->mm);
if (npgs != umem->npgs) {
--
2.40.0
^ permalink raw reply related [flat|nested] 4+ messages in thread