From: Yulei Zhang <yuleixzhang@xxxxxxxxxxx>
It adds mempolicy support for dmem to allocates memory
from mempolicy specified nodes.
Signed-off-by: Haiwei Li <gerryhwli@xxxxxxxxxxx>
Signed-off-by: Yulei Zhang <yuleixzhang@xxxxxxxxxxx>
---
arch/x86/Kconfig | 1 +
arch/x86/include/asm/pgtable.h | 7 ++++
arch/x86/include/asm/pgtable_types.h | 13 +++++-
fs/dmemfs/Kconfig | 3 ++
include/linux/pgtable.h | 7 ++++
mm/Kconfig | 3 ++
mm/dmem.c | 63 +++++++++++++++++++++++++++-
7 files changed, 94 insertions(+), 3 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7101ac64bb20..86f3139edfc7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -73,6 +73,7 @@ config X86
select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
select ARCH_HAS_PMEM_API if X86_64
select ARCH_HAS_PTE_DEVMAP if X86_64
+ select ARCH_HAS_PTE_DMEM if X86_64
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index b836138ce852..ea4554a728bc 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -453,6 +453,13 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd)
return pmd_set_flags(pmd, _PAGE_DEVMAP);
}
+#ifdef CONFIG_ARCH_HAS_PTE_DMEM
+static inline pmd_t pmd_mkdmem(pmd_t pmd)
+{
+ return pmd_set_flags(pmd, _PAGE_SPECIAL | _PAGE_DMEM);
+}
+#endif
+
static inline pmd_t pmd_mkhuge(pmd_t pmd)
{
return pmd_set_flags(pmd, _PAGE_PSE);
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 816b31c68550..ee4cae110f5c 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -23,6 +23,15 @@
#define _PAGE_BIT_SOFTW2 10 /* " */
#define _PAGE_BIT_SOFTW3 11 /* " */
#define _PAGE_BIT_PAT_LARGE 12 /* On 2MB or 1GB pages */
+#define _PAGE_BIT_DMEM 57 /* Flag used to indicate dmem pmd.
+ * Since _PAGE_BIT_SPECIAL is defined
+ * same as _PAGE_BIT_CPA_TEST, we can
+ * not only use _PAGE_BIT_SPECIAL, so
+ * add _PAGE_BIT_DMEM to help
+ * indicate it. Since dmem pte will
+ * never be splitting, setting
+ * _PAGE_BIT_SPECIAL for pte is enough.
+ */
#define _PAGE_BIT_SOFTW4 58 /* available for programmer */
#define _PAGE_BIT_PKEY_BIT0 59 /* Protection Keys, bit 1/4 */
#define _PAGE_BIT_PKEY_BIT1 60 /* Protection Keys, bit 2/4 */
@@ -112,9 +121,11 @@
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
#define _PAGE_NX (_AT(pteval_t, 1) << _PAGE_BIT_NX)
#define _PAGE_DEVMAP (_AT(u64, 1) << _PAGE_BIT_DEVMAP)
+#define _PAGE_DMEM (_AT(u64, 1) << _PAGE_BIT_DMEM)
#else
#define _PAGE_NX (_AT(pteval_t, 0))
#define _PAGE_DEVMAP (_AT(pteval_t, 0))
+#define _PAGE_DMEM (_AT(pteval_t, 0))
#endif
#define _PAGE_PROTNONE (_AT(pteval_t, 1) << _PAGE_BIT_PROTNONE)
@@ -128,7 +139,7 @@
#define _PAGE_CHG_MASK (PTE_PFN_MASK | _PAGE_PCD | _PAGE_PWT | \
_PAGE_SPECIAL | _PAGE_ACCESSED | _PAGE_DIRTY | \
_PAGE_SOFT_DIRTY | _PAGE_DEVMAP | _PAGE_ENC | \
- _PAGE_UFFD_WP)
+ _PAGE_UFFD_WP | _PAGE_DMEM)
#define _HPAGE_CHG_MASK (_PAGE_CHG_MASK | _PAGE_PSE)
/*
diff --git a/fs/dmemfs/Kconfig b/fs/dmemfs/Kconfig
index d2894a513de0..19ca3914da39 100644
--- a/fs/dmemfs/Kconfig
+++ b/fs/dmemfs/Kconfig
@@ -1,5 +1,8 @@
config DMEM_FS
tristate "Direct Memory filesystem support"
+ depends on DMEM
+ depends on TRANSPARENT_HUGEPAGE
+ depends on ARCH_HAS_PTE_DMEM
help
dmemfs (Direct Memory filesystem) is device memory or reserved
memory based filesystem. This kind of memory is special as it
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index e8cbc2e795d5..45d4c4a3e519 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1129,6 +1129,13 @@ static inline int pud_trans_unstable(pud_t *pud)
#endif
}
+#ifndef CONFIG_ARCH_HAS_PTE_DMEM
+static inline pmd_t pmd_mkdmem(pmd_t pmd)
+{
+ return pmd;
+}
+#endif
+
#ifndef pmd_read_atomic
static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
{
diff --git a/mm/Kconfig b/mm/Kconfig
index 8a67c8933a42..09d1b1551a44 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -795,6 +795,9 @@ config IDLE_PAGE_TRACKING
config ARCH_HAS_PTE_DEVMAP
bool
+config ARCH_HAS_PTE_DMEM
+ bool
+
config ZONE_DEVICE
bool "Device memory (pmem, HMM, etc...) hotplug support"
depends on MEMORY_HOTPLUG
diff --git a/mm/dmem.c b/mm/dmem.c
index 6992e57d5df0..2e61dbddbc62 100644
--- a/mm/dmem.c
+++ b/mm/dmem.c
@@ -822,6 +822,56 @@ dmem_alloc_pages_nodemask(int nid, nodemask_t *nodemask, unsigned int try_max,
}
EXPORT_SYMBOL(dmem_alloc_pages_nodemask);
+/* Return a nodelist indicated for current node representing a mempolicy */
+static int *policy_nodelist(struct mempolicy *policy)
+{
+ int nd = numa_node_id();
+
+ switch (policy->mode) {
+ case MPOL_PREFERRED:
+ if (!(policy->flags & MPOL_F_LOCAL))
+ nd = policy->v.preferred_node;
+ break;
+ case MPOL_BIND:
+ if (unlikely(!node_isset(nd, policy->v.nodes)))
+ nd = first_node(policy->v.nodes);
+ break;
+ default:
+ WARN_ON(1);
+ }
+ return dmem_nodelist(nd);
+}
+
+static nodemask_t *dmem_policy_nodemask(struct mempolicy *policy)
+{
+ if (unlikely(policy->mode == MPOL_BIND) &&
+ cpuset_nodemask_valid_mems_allowed(&policy->v.nodes))
+ return &policy->v.nodes;
+
+ return NULL;
+}
+
+static void
+get_mempolicy_nlist_and_nmask(struct mempolicy *pol,
+ struct vm_area_struct *vma, unsigned long addr,
+ int **nl, nodemask_t **nmask)
+{
+ if (pol->mode == MPOL_INTERLEAVE) {
+ unsigned int nid;
+
+ /*
+ * we use dpage_shift to interleave numa nodes although
+ * multiple dpages may be allocated
+ */
+ nid = interleave_nid(pol, vma, addr, dmem_pool.dpage_shift);
+ *nl = dmem_nodelist(nid);
+ *nmask = NULL;
+ } else {
+ *nl = policy_nodelist(pol);
+ *nmask = dmem_policy_nodemask(pol);
+ }
+}
+
/*
* dmem_alloc_pages_vma - Allocate pages for a VMA.
*
@@ -830,6 +880,9 @@ EXPORT_SYMBOL(dmem_alloc_pages_nodemask);
* @try_max: try to allocate @try_max dpages if possible
* @result_nr: allocated dpage number returned to the caller
*
+ * This function allocates pages from dmem pool and applies a NUMA policy
+ * associated with the VMA.
+ *
* Return the physical address of the first dpage allocated from dmem
* pool, or 0 on failure. The allocated dpage number is filled into
* @result_nr
@@ -839,13 +892,19 @@ dmem_alloc_pages_vma(struct vm_area_struct *vma, unsigned long addr,
unsigned int try_max, unsigned int *result_nr)
{
phys_addr_t phys_addr;
+ struct mempolicy *pol;
int *nl;
+ nodemask_t *nmask;
unsigned int cpuset_mems_cookie;
retry_cpuset:
- nl = dmem_nodelist(numa_node_id());
+ pol = get_vma_policy(vma, addr);
+ cpuset_mems_cookie = read_mems_allowed_begin();
+
+ get_mempolicy_nlist_and_nmask(pol, vma, addr, &nl, &nmask);
+ mpol_cond_put(pol);
- phys_addr = dmem_alloc_pages_from_nodelist(nl, NULL, try_max,
+ phys_addr = dmem_alloc_pages_from_nodelist(nl, nmask, try_max,
result_nr);
if (unlikely(!phys_addr && read_mems_allowed_retry(cpuset_mems_cookie)))
goto retry_cpuset;
--
2.28.0
