Re: [PATCHv3 04/17] mm/page_alloc: Handle allocation for encrypted memory
On Wed, Jun 13, 2018 at 06:07:40PM +, Dave Hansen wrote:
> On 06/12/2018 07:39 AM, Kirill A. Shutemov wrote:
> > For encrypted memory, we need to allocated pages for a specific
> > encryption KeyID.
>
> "allocate" ^
>
> > There are two cases when we need to allocate a page for encryption:
> >
> > - Allocation for an encrypted VMA;
> >
> > - Allocation for migration of encrypted page;
> >
> > The first case can be covered within alloc_page_vma().
>
> ... because we know the KeyID from the VMA?
Right. I'll update commit message.
> > The second case requires few new page allocation routines that would
> > allocate the page for a specific KeyID.
> >
> > Encrypted page has to be cleared after KeyID set. This is handled by
>
> "An encrypted page has ... "
>
> This description lacks a description of the performance impact of the
> approach in this patch both when allocating encrypted and normal pages.
You are right. I'll measure for the next iteration.
> > --- a/arch/alpha/include/asm/page.h
> > +++ b/arch/alpha/include/asm/page.h
> > @@ -18,7 +18,7 @@ extern void clear_page(void *page);
> > #define clear_user_page(page, vaddr, pg) clear_page(page)
> >
> > #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \
> > - alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vmaddr)
> > + alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
> > #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
>
> Does this compile? Wouldn't "vmaddr" be undefined?
Yes, it compiles.
Before I reorganized macros around alloc_page_vma(), the argument was
ignored for non-NUMA systems. NUMA on Alpha marked BROKEN and never
enabled.
> > +#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
> > + alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
>
> The argument addition should be broken out into a preparatory patch.
There's no new argument. I've just unified alloc_hugepage_vma() codepath
for NUMA and non-NUMA.
But sure I'll split it into a separate patch.
> > extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
> > extern unsigned long get_zeroed_page(gfp_t gfp_mask);
> > diff --git a/include/linux/migrate.h b/include/linux/migrate.h
> > index f2b4abbca55e..6da504bad841 100644
> > --- a/include/linux/migrate.h
> > +++ b/include/linux/migrate.h
> > @@ -38,9 +38,11 @@ static inline struct page *new_page_nodemask(struct page
> > *page,
> > unsigned int order = 0;
> > struct page *new_page = NULL;
> >
> > - if (PageHuge(page))
> > + if (PageHuge(page)) {
> > + WARN_ON(page_keyid(page));
> > return
> > alloc_huge_page_nodemask(page_hstate(compound_head(page)),
> > preferred_nid, nodemask);
> > + }
>
> Comment on the warning, please.
Sure.
> > diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> > index 9ac49ef17b4e..00bccbececea 100644
> > --- a/mm/mempolicy.c
> > +++ b/mm/mempolicy.c
> > @@ -920,22 +920,24 @@ static void migrate_page_add(struct page *page,
> > struct list_head *pagelist,
> > /* page allocation callback for NUMA node migration */
> > struct page *alloc_new_node_page(struct page *page, unsigned long node)
> > {
> > - if (PageHuge(page))
> > + if (PageHuge(page)) {
> > + WARN_ON(page_keyid(page));
> > return alloc_huge_page_node(page_hstate(compound_head(page)),
> > node);
>
> Comments, please.
>
> > @@ -2012,9 +2014,16 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> > vm_area_struct *vma,
> > {
> > struct mempolicy *pol;
> > struct page *page;
> > - int preferred_nid;
> > + bool zero = false;
> > + int keyid, preferred_nid;
> > nodemask_t *nmask;
> >
> > + keyid = vma_keyid(vma);
> > + if (keyid && gfp & __GFP_ZERO) {
> > + zero = true;
> > + gfp &= ~__GFP_ZERO;
> > + }
>
> I totally read that wrong.
>
> "zero" needs to be named: "page_need_zeroing".
>
> It also badly needs a comment.
Got it.
> > pol = get_vma_policy(vma, addr);
> >
> > if (pol->mode == MPOL_INTERLEAVE) {
> > @@ -2057,6 +2066,8 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> > vm_area_struct *vma,
> > page = __alloc_pages_nodemask(gfp, order, preferred_nid, nmask);
> > mpol_cond_put(pol);
> > out:
> > + if (page && keyid)
> > + prep_encrypted_page(page, order, keyid, zero);
> > return page;
> > }
>
> I'd just have prep_encrypted_page() do the keyid-0 opt-out of the prep
> work. It'll be less to patch when you
Makes sense.
> > diff --git a/mm/migrate.c b/mm/migrate.c
> > index 8c0af0f7cab1..eb8dea219dcb 100644
> > --- a/mm/migrate.c
> > +++ b/mm/migrate.c
> > @@ -1847,7 +1847,7 @@ static struct page *alloc_misplaced_dst_page(struct
> > page *page,
> > int nid = (int) data;
> > struct page *newpage;
> >
> > - newpage = __alloc_pages_node(nid,
> > + newpage = __alloc_pages_node_keyid(nid,
Re: [PATCHv3 04/17] mm/page_alloc: Handle allocation for encrypted memory
On Wed, Jun 13, 2018 at 06:07:40PM +, Dave Hansen wrote:
> On 06/12/2018 07:39 AM, Kirill A. Shutemov wrote:
> > For encrypted memory, we need to allocated pages for a specific
> > encryption KeyID.
>
> "allocate" ^
>
> > There are two cases when we need to allocate a page for encryption:
> >
> > - Allocation for an encrypted VMA;
> >
> > - Allocation for migration of encrypted page;
> >
> > The first case can be covered within alloc_page_vma().
>
> ... because we know the KeyID from the VMA?
Right. I'll update commit message.
> > The second case requires few new page allocation routines that would
> > allocate the page for a specific KeyID.
> >
> > Encrypted page has to be cleared after KeyID set. This is handled by
>
> "An encrypted page has ... "
>
> This description lacks a description of the performance impact of the
> approach in this patch both when allocating encrypted and normal pages.
You are right. I'll measure for the next iteration.
> > --- a/arch/alpha/include/asm/page.h
> > +++ b/arch/alpha/include/asm/page.h
> > @@ -18,7 +18,7 @@ extern void clear_page(void *page);
> > #define clear_user_page(page, vaddr, pg) clear_page(page)
> >
> > #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \
> > - alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vmaddr)
> > + alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
> > #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
>
> Does this compile? Wouldn't "vmaddr" be undefined?
Yes, it compiles.
Before I reorganized macros around alloc_page_vma(), the argument was
ignored for non-NUMA systems. NUMA on Alpha marked BROKEN and never
enabled.
> > +#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
> > + alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
>
> The argument addition should be broken out into a preparatory patch.
There's no new argument. I've just unified alloc_hugepage_vma() codepath
for NUMA and non-NUMA.
But sure I'll split it into a separate patch.
> > extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
> > extern unsigned long get_zeroed_page(gfp_t gfp_mask);
> > diff --git a/include/linux/migrate.h b/include/linux/migrate.h
> > index f2b4abbca55e..6da504bad841 100644
> > --- a/include/linux/migrate.h
> > +++ b/include/linux/migrate.h
> > @@ -38,9 +38,11 @@ static inline struct page *new_page_nodemask(struct page
> > *page,
> > unsigned int order = 0;
> > struct page *new_page = NULL;
> >
> > - if (PageHuge(page))
> > + if (PageHuge(page)) {
> > + WARN_ON(page_keyid(page));
> > return
> > alloc_huge_page_nodemask(page_hstate(compound_head(page)),
> > preferred_nid, nodemask);
> > + }
>
> Comment on the warning, please.
Sure.
> > diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> > index 9ac49ef17b4e..00bccbececea 100644
> > --- a/mm/mempolicy.c
> > +++ b/mm/mempolicy.c
> > @@ -920,22 +920,24 @@ static void migrate_page_add(struct page *page,
> > struct list_head *pagelist,
> > /* page allocation callback for NUMA node migration */
> > struct page *alloc_new_node_page(struct page *page, unsigned long node)
> > {
> > - if (PageHuge(page))
> > + if (PageHuge(page)) {
> > + WARN_ON(page_keyid(page));
> > return alloc_huge_page_node(page_hstate(compound_head(page)),
> > node);
>
> Comments, please.
>
> > @@ -2012,9 +2014,16 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> > vm_area_struct *vma,
> > {
> > struct mempolicy *pol;
> > struct page *page;
> > - int preferred_nid;
> > + bool zero = false;
> > + int keyid, preferred_nid;
> > nodemask_t *nmask;
> >
> > + keyid = vma_keyid(vma);
> > + if (keyid && gfp & __GFP_ZERO) {
> > + zero = true;
> > + gfp &= ~__GFP_ZERO;
> > + }
>
> I totally read that wrong.
>
> "zero" needs to be named: "page_need_zeroing".
>
> It also badly needs a comment.
Got it.
> > pol = get_vma_policy(vma, addr);
> >
> > if (pol->mode == MPOL_INTERLEAVE) {
> > @@ -2057,6 +2066,8 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> > vm_area_struct *vma,
> > page = __alloc_pages_nodemask(gfp, order, preferred_nid, nmask);
> > mpol_cond_put(pol);
> > out:
> > + if (page && keyid)
> > + prep_encrypted_page(page, order, keyid, zero);
> > return page;
> > }
>
> I'd just have prep_encrypted_page() do the keyid-0 opt-out of the prep
> work. It'll be less to patch when you
Makes sense.
> > diff --git a/mm/migrate.c b/mm/migrate.c
> > index 8c0af0f7cab1..eb8dea219dcb 100644
> > --- a/mm/migrate.c
> > +++ b/mm/migrate.c
> > @@ -1847,7 +1847,7 @@ static struct page *alloc_misplaced_dst_page(struct
> > page *page,
> > int nid = (int) data;
> > struct page *newpage;
> >
> > - newpage = __alloc_pages_node(nid,
> > + newpage = __alloc_pages_node_keyid(nid,
Re: [PATCHv3 04/17] mm/page_alloc: Handle allocation for encrypted memory
On 06/12/2018 07:39 AM, Kirill A. Shutemov wrote:
> For encrypted memory, we need to allocated pages for a specific
> encryption KeyID.
"allocate" ^
> There are two cases when we need to allocate a page for encryption:
>
> - Allocation for an encrypted VMA;
>
> - Allocation for migration of encrypted page;
>
> The first case can be covered within alloc_page_vma().
... because we know the KeyID from the VMA?
> The second case requires few new page allocation routines that would
> allocate the page for a specific KeyID.
>
> Encrypted page has to be cleared after KeyID set. This is handled by
"An encrypted page has ... "
This description lacks a description of the performance impact of the
approach in this patch both when allocating encrypted and normal pages.
> --- a/arch/alpha/include/asm/page.h
> +++ b/arch/alpha/include/asm/page.h
> @@ -18,7 +18,7 @@ extern void clear_page(void *page);
> #define clear_user_page(page, vaddr, pg) clear_page(page)
>
> #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \
> - alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vmaddr)
> + alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
> #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
Does this compile? Wouldn't "vmaddr" be undefined?
> +#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
> + alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
The argument addition should be broken out into a preparatory patch.
> extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
> extern unsigned long get_zeroed_page(gfp_t gfp_mask);
> diff --git a/include/linux/migrate.h b/include/linux/migrate.h
> index f2b4abbca55e..6da504bad841 100644
> --- a/include/linux/migrate.h
> +++ b/include/linux/migrate.h
> @@ -38,9 +38,11 @@ static inline struct page *new_page_nodemask(struct page
> *page,
> unsigned int order = 0;
> struct page *new_page = NULL;
>
> - if (PageHuge(page))
> + if (PageHuge(page)) {
> + WARN_ON(page_keyid(page));
> return
> alloc_huge_page_nodemask(page_hstate(compound_head(page)),
> preferred_nid, nodemask);
> + }
Comment on the warning, please.
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index 9ac49ef17b4e..00bccbececea 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -920,22 +920,24 @@ static void migrate_page_add(struct page *page, struct
> list_head *pagelist,
> /* page allocation callback for NUMA node migration */
> struct page *alloc_new_node_page(struct page *page, unsigned long node)
> {
> - if (PageHuge(page))
> + if (PageHuge(page)) {
> + WARN_ON(page_keyid(page));
> return alloc_huge_page_node(page_hstate(compound_head(page)),
> node);
Comments, please.
> @@ -2012,9 +2014,16 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> vm_area_struct *vma,
> {
> struct mempolicy *pol;
> struct page *page;
> - int preferred_nid;
> + bool zero = false;
> + int keyid, preferred_nid;
> nodemask_t *nmask;
>
> + keyid = vma_keyid(vma);
> + if (keyid && gfp & __GFP_ZERO) {
> + zero = true;
> + gfp &= ~__GFP_ZERO;
> + }
I totally read that wrong.
"zero" needs to be named: "page_need_zeroing".
It also badly needs a comment.
> pol = get_vma_policy(vma, addr);
>
> if (pol->mode == MPOL_INTERLEAVE) {
> @@ -2057,6 +2066,8 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> vm_area_struct *vma,
> page = __alloc_pages_nodemask(gfp, order, preferred_nid, nmask);
> mpol_cond_put(pol);
> out:
> + if (page && keyid)
> + prep_encrypted_page(page, order, keyid, zero);
> return page;
> }
I'd just have prep_encrypted_page() do the keyid-0 opt-out of the prep
work. It'll be less to patch when you
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 8c0af0f7cab1..eb8dea219dcb 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1847,7 +1847,7 @@ static struct page *alloc_misplaced_dst_page(struct
> page *page,
> int nid = (int) data;
> struct page *newpage;
>
> - newpage = __alloc_pages_node(nid,
> + newpage = __alloc_pages_node_keyid(nid, page_keyid(page),
>(GFP_HIGHUSER_MOVABLE |
> __GFP_THISNODE | __GFP_NOMEMALLOC |
> __GFP_NORETRY | __GFP_NOWARN) &
I thought folks asked you not to change all of the calling conventions
across the page allocator. It seems like you're still doing that,
though. A reviewer might think you've ignored their earlier feedback.
Did you?
> +#ifndef CONFIG_NUMA
> +struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
> + struct vm_area_struct *vma, unsigned long addr,
> + int node, bool hugepage)
> +{
> +
Re: [PATCHv3 04/17] mm/page_alloc: Handle allocation for encrypted memory
On 06/12/2018 07:39 AM, Kirill A. Shutemov wrote:
> For encrypted memory, we need to allocated pages for a specific
> encryption KeyID.
"allocate" ^
> There are two cases when we need to allocate a page for encryption:
>
> - Allocation for an encrypted VMA;
>
> - Allocation for migration of encrypted page;
>
> The first case can be covered within alloc_page_vma().
... because we know the KeyID from the VMA?
> The second case requires few new page allocation routines that would
> allocate the page for a specific KeyID.
>
> Encrypted page has to be cleared after KeyID set. This is handled by
"An encrypted page has ... "
This description lacks a description of the performance impact of the
approach in this patch both when allocating encrypted and normal pages.
> --- a/arch/alpha/include/asm/page.h
> +++ b/arch/alpha/include/asm/page.h
> @@ -18,7 +18,7 @@ extern void clear_page(void *page);
> #define clear_user_page(page, vaddr, pg) clear_page(page)
>
> #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \
> - alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vmaddr)
> + alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
> #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
Does this compile? Wouldn't "vmaddr" be undefined?
> +#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
> + alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
The argument addition should be broken out into a preparatory patch.
> extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
> extern unsigned long get_zeroed_page(gfp_t gfp_mask);
> diff --git a/include/linux/migrate.h b/include/linux/migrate.h
> index f2b4abbca55e..6da504bad841 100644
> --- a/include/linux/migrate.h
> +++ b/include/linux/migrate.h
> @@ -38,9 +38,11 @@ static inline struct page *new_page_nodemask(struct page
> *page,
> unsigned int order = 0;
> struct page *new_page = NULL;
>
> - if (PageHuge(page))
> + if (PageHuge(page)) {
> + WARN_ON(page_keyid(page));
> return
> alloc_huge_page_nodemask(page_hstate(compound_head(page)),
> preferred_nid, nodemask);
> + }
Comment on the warning, please.
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index 9ac49ef17b4e..00bccbececea 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -920,22 +920,24 @@ static void migrate_page_add(struct page *page, struct
> list_head *pagelist,
> /* page allocation callback for NUMA node migration */
> struct page *alloc_new_node_page(struct page *page, unsigned long node)
> {
> - if (PageHuge(page))
> + if (PageHuge(page)) {
> + WARN_ON(page_keyid(page));
> return alloc_huge_page_node(page_hstate(compound_head(page)),
> node);
Comments, please.
> @@ -2012,9 +2014,16 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> vm_area_struct *vma,
> {
> struct mempolicy *pol;
> struct page *page;
> - int preferred_nid;
> + bool zero = false;
> + int keyid, preferred_nid;
> nodemask_t *nmask;
>
> + keyid = vma_keyid(vma);
> + if (keyid && gfp & __GFP_ZERO) {
> + zero = true;
> + gfp &= ~__GFP_ZERO;
> + }
I totally read that wrong.
"zero" needs to be named: "page_need_zeroing".
It also badly needs a comment.
> pol = get_vma_policy(vma, addr);
>
> if (pol->mode == MPOL_INTERLEAVE) {
> @@ -2057,6 +2066,8 @@ alloc_pages_vma(gfp_t gfp, int order, struct
> vm_area_struct *vma,
> page = __alloc_pages_nodemask(gfp, order, preferred_nid, nmask);
> mpol_cond_put(pol);
> out:
> + if (page && keyid)
> + prep_encrypted_page(page, order, keyid, zero);
> return page;
> }
I'd just have prep_encrypted_page() do the keyid-0 opt-out of the prep
work. It'll be less to patch when you
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 8c0af0f7cab1..eb8dea219dcb 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1847,7 +1847,7 @@ static struct page *alloc_misplaced_dst_page(struct
> page *page,
> int nid = (int) data;
> struct page *newpage;
>
> - newpage = __alloc_pages_node(nid,
> + newpage = __alloc_pages_node_keyid(nid, page_keyid(page),
>(GFP_HIGHUSER_MOVABLE |
> __GFP_THISNODE | __GFP_NOMEMALLOC |
> __GFP_NORETRY | __GFP_NOWARN) &
I thought folks asked you not to change all of the calling conventions
across the page allocator. It seems like you're still doing that,
though. A reviewer might think you've ignored their earlier feedback.
Did you?
> +#ifndef CONFIG_NUMA
> +struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
> + struct vm_area_struct *vma, unsigned long addr,
> + int node, bool hugepage)
> +{
> +
