[PATCH 2/4] mm: split up mm_struct to separate header file
From: Kirill A. Shutemov
Date: Wed Jan 28 2015 - 15:17:00 EST
We want to use __PAGETABLE_PMD_FOLDED in mm_struct to drop nr_pmds if
pmd is folded. __PAGETABLE_PMD_FOLDED is defined in <asm/pgtable.h>, but
<asm/pgtable.h> itself wants <linux/mm_types.h> for struct page
definition.
This patch move mm_struct definition into separate header file in order
to fix circular header dependencies.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
arch/arm64/kernel/efi.c | 1 +
arch/c6x/kernel/dma.c | 1 -
arch/s390/include/asm/pgtable.h | 1 +
arch/x86/include/asm/mmu_context.h | 1 +
arch/x86/include/asm/pgtable.h | 15 +--
drivers/iommu/amd_iommu_v2.c | 1 +
drivers/staging/android/ion/ion.c | 1 -
include/linux/mm.h | 1 +
include/linux/mm_struct.h | 214 ++++++++++++++++++++++++++++++++++++
include/linux/mm_types.h | 218 ++-----------------------------------
include/linux/mmu_notifier.h | 1 +
include/linux/sched.h | 1 +
mm/init-mm.c | 1 +
mm/kmemcheck.c | 1 -
14 files changed, 232 insertions(+), 226 deletions(-)
create mode 100644 include/linux/mm_struct.h
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index b42c7b480e1e..fbf0a6d6f691 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -17,6 +17,7 @@
#include <linux/export.h>
#include <linux/memblock.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/bootmem.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
diff --git a/arch/c6x/kernel/dma.c b/arch/c6x/kernel/dma.c
index ab7b12de144d..5a489f1eabbd 100644
--- a/arch/c6x/kernel/dma.c
+++ b/arch/c6x/kernel/dma.c
@@ -9,7 +9,6 @@
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <linux/mm.h>
-#include <linux/mm_types.h>
#include <linux/scatterlist.h>
#include <asm/cacheflush.h>
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index fbb5ee3ae57c..578eb098b1be 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -29,6 +29,7 @@
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/page-flags.h>
#include <linux/radix-tree.h>
#include <asm/bug.h>
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 4b75d591eb5e..78a87a30ec50 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -4,6 +4,7 @@
#include <asm/desc.h>
#include <linux/atomic.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <trace/events/tlb.h>
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 9d0ade00923e..594d09d07bb4 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -445,18 +445,9 @@ static inline int pte_present(pte_t a)
return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE);
}
-#define pte_accessible pte_accessible
-static inline bool pte_accessible(struct mm_struct *mm, pte_t a)
-{
- if (pte_flags(a) & _PAGE_PRESENT)
- return true;
-
- if ((pte_flags(a) & _PAGE_PROTNONE) &&
- mm_tlb_flush_pending(mm))
- return true;
-
- return false;
-}
+#define pte_accessible(mm, pte) \
+ (pte_flags(pte) & _PAGE_PRESENT) || \
+ ((pte_flags(pte) & _PAGE_PROTNONE) && mm_tlb_flush_pending(mm))
static inline int pte_hidden(pte_t pte)
{
diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index 90f70d0e1141..d49cd95eaf7b 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -19,6 +19,7 @@
#include <linux/mmu_notifier.h>
#include <linux/amd-iommu.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/profile.h>
#include <linux/module.h>
#include <linux/sched.h>
diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index b8f1c491553e..1cb3c88f6423 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -27,7 +27,6 @@
#include <linux/miscdevice.h>
#include <linux/export.h>
#include <linux/mm.h>
-#include <linux/mm_types.h>
#include <linux/rbtree.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index b976d9ffbcd6..543e9723d441 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -14,6 +14,7 @@
#include <linux/atomic.h>
#include <linux/debug_locks.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/range.h>
#include <linux/pfn.h>
#include <linux/bit_spinlock.h>
diff --git a/include/linux/mm_struct.h b/include/linux/mm_struct.h
new file mode 100644
index 000000000000..0a233c232a39
--- /dev/null
+++ b/include/linux/mm_struct.h
@@ -0,0 +1,214 @@
+#ifndef _LINUX_MM_STRUCT_H
+#define _LINUX_MM_STRUCT_H
+
+#include <linux/auxvec.h>
+#include <linux/rbtree.h>
+#include <linux/rwsem.h>
+#include <linux/types.h>
+#include <linux/uprobes.h>
+
+#include <asm/mmu.h>
+
+struct kioctx_table;
+struct vm_area_struct;
+
+#ifndef AT_VECTOR_SIZE_ARCH
+#define AT_VECTOR_SIZE_ARCH 0
+#endif
+#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
+
+enum {
+ MM_FILEPAGES,
+ MM_ANONPAGES,
+ MM_SWAPENTS,
+ NR_MM_COUNTERS
+};
+
+#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS && defined(CONFIG_MMU)
+#define SPLIT_RSS_COUNTING
+/* per-thread cached information, */
+struct task_rss_stat {
+ int events; /* for synchronization threshold */
+ int count[NR_MM_COUNTERS];
+};
+#endif /* USE_SPLIT_PTE_PTLOCKS */
+
+struct mm_rss_stat {
+ atomic_long_t count[NR_MM_COUNTERS];
+};
+
+struct mm_struct {
+ struct vm_area_struct *mmap; /* list of VMAs */
+ struct rb_root mm_rb;
+ u32 vmacache_seqnum; /* per-thread vmacache */
+#ifdef CONFIG_MMU
+ unsigned long (*get_unmapped_area) (struct file *filp,
+ unsigned long addr, unsigned long len,
+ unsigned long pgoff, unsigned long flags);
+#endif
+ unsigned long mmap_base; /* base of mmap area */
+ unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */
+ unsigned long task_size; /* size of task vm space */
+ unsigned long highest_vm_end; /* highest vma end address */
+ pgd_t * pgd;
+ atomic_t mm_users; /* How many users with user space? */
+ atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
+ atomic_long_t nr_ptes; /* PTE page table pages */
+ atomic_long_t nr_pmds; /* PMD page table pages */
+ int map_count; /* number of VMAs */
+
+ spinlock_t page_table_lock; /* Protects page tables and some counters */
+ struct rw_semaphore mmap_sem;
+
+ struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
+ * together off init_mm.mmlist, and are protected
+ * by mmlist_lock
+ */
+
+
+ unsigned long hiwater_rss; /* High-watermark of RSS usage */
+ unsigned long hiwater_vm; /* High-water virtual memory usage */
+
+ unsigned long total_vm; /* Total pages mapped */
+ unsigned long locked_vm; /* Pages that have PG_mlocked set */
+ unsigned long pinned_vm; /* Refcount permanently increased */
+ unsigned long shared_vm; /* Shared pages (files) */
+ unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE */
+ unsigned long stack_vm; /* VM_GROWSUP/DOWN */
+ unsigned long def_flags;
+ unsigned long start_code, end_code, start_data, end_data;
+ unsigned long start_brk, brk, start_stack;
+ unsigned long arg_start, arg_end, env_start, env_end;
+
+ unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
+
+ /*
+ * Special counters, in some configurations protected by the
+ * page_table_lock, in other configurations by being atomic.
+ */
+ struct mm_rss_stat rss_stat;
+
+ struct linux_binfmt *binfmt;
+
+ cpumask_var_t cpu_vm_mask_var;
+
+ /* Architecture-specific MM context */
+ mm_context_t context;
+
+ unsigned long flags; /* Must use atomic bitops to access the bits */
+
+ struct core_state *core_state; /* coredumping support */
+#ifdef CONFIG_AIO
+ spinlock_t ioctx_lock;
+ struct kioctx_table __rcu *ioctx_table;
+#endif
+#ifdef CONFIG_MEMCG
+ /*
+ * "owner" points to a task that is regarded as the canonical
+ * user/owner of this mm. All of the following must be true in
+ * order for it to be changed:
+ *
+ * current == mm->owner
+ * current->mm != mm
+ * new_owner->mm == mm
+ * new_owner->alloc_lock is held
+ */
+ struct task_struct __rcu *owner;
+#endif
+
+ /* store ref to file /proc/<pid>/exe symlink points to */
+ struct file *exe_file;
+#ifdef CONFIG_MMU_NOTIFIER
+ struct mmu_notifier_mm *mmu_notifier_mm;
+#endif
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
+ pgtable_t pmd_huge_pte; /* protected by page_table_lock */
+#endif
+#ifdef CONFIG_CPUMASK_OFFSTACK
+ struct cpumask cpumask_allocation;
+#endif
+#ifdef CONFIG_NUMA_BALANCING
+ /*
+ * numa_next_scan is the next time that the PTEs will be marked
+ * pte_numa. NUMA hinting faults will gather statistics and migrate
+ * pages to new nodes if necessary.
+ */
+ unsigned long numa_next_scan;
+
+ /* Restart point for scanning and setting pte_numa */
+ unsigned long numa_scan_offset;
+
+ /* numa_scan_seq prevents two threads setting pte_numa */
+ int numa_scan_seq;
+#endif
+#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
+ /*
+ * An operation with batched TLB flushing is going on. Anything that
+ * can move process memory needs to flush the TLB when moving a
+ * PROT_NONE or PROT_NUMA mapped page.
+ */
+ bool tlb_flush_pending;
+#endif
+ struct uprobes_state uprobes_state;
+#ifdef CONFIG_X86_INTEL_MPX
+ /* address of the bounds directory */
+ void __user *bd_addr;
+#endif
+};
+
+static inline void mm_init_cpumask(struct mm_struct *mm)
+{
+#ifdef CONFIG_CPUMASK_OFFSTACK
+ mm->cpu_vm_mask_var = &mm->cpumask_allocation;
+#endif
+ cpumask_clear(mm->cpu_vm_mask_var);
+}
+
+/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
+static inline cpumask_t *mm_cpumask(struct mm_struct *mm)
+{
+ return mm->cpu_vm_mask_var;
+}
+
+#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
+/*
+ * Memory barriers to keep this state in sync are graciously provided by
+ * the page table locks, outside of which no page table modifications happen.
+ * The barriers below prevent the compiler from re-ordering the instructions
+ * around the memory barriers that are already present in the code.
+ */
+static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
+{
+ barrier();
+ return mm->tlb_flush_pending;
+}
+static inline void set_tlb_flush_pending(struct mm_struct *mm)
+{
+ mm->tlb_flush_pending = true;
+
+ /*
+ * Guarantee that the tlb_flush_pending store does not leak into the
+ * critical section updating the page tables
+ */
+ smp_mb__before_spinlock();
+}
+/* Clearing is done after a TLB flush, which also provides a barrier. */
+static inline void clear_tlb_flush_pending(struct mm_struct *mm)
+{
+ barrier();
+ mm->tlb_flush_pending = false;
+}
+#else
+static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
+{
+ return false;
+}
+static inline void set_tlb_flush_pending(struct mm_struct *mm)
+{
+}
+static inline void clear_tlb_flush_pending(struct mm_struct *mm)
+{
+}
+#endif
+
+#endif
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 5dfdd5ed5254..80797b1c1e26 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -1,24 +1,16 @@
#ifndef _LINUX_MM_TYPES_H
#define _LINUX_MM_TYPES_H
-#include <linux/auxvec.h>
-#include <linux/types.h>
-#include <linux/threads.h>
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/rbtree.h>
-#include <linux/rwsem.h>
#include <linux/completion.h>
#include <linux/cpumask.h>
-#include <linux/uprobes.h>
+#include <linux/list.h>
#include <linux/page-flags-layout.h>
-#include <asm/page.h>
-#include <asm/mmu.h>
+#include <linux/rbtree.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+#include <linux/types.h>
-#ifndef AT_VECTOR_SIZE_ARCH
-#define AT_VECTOR_SIZE_ARCH 0
-#endif
-#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
+#include <asm/page.h>
struct address_space;
struct mem_cgroup;
@@ -326,203 +318,7 @@ struct core_state {
struct completion startup;
};
-enum {
- MM_FILEPAGES,
- MM_ANONPAGES,
- MM_SWAPENTS,
- NR_MM_COUNTERS
-};
-
-#if USE_SPLIT_PTE_PTLOCKS && defined(CONFIG_MMU)
-#define SPLIT_RSS_COUNTING
-/* per-thread cached information, */
-struct task_rss_stat {
- int events; /* for synchronization threshold */
- int count[NR_MM_COUNTERS];
-};
-#endif /* USE_SPLIT_PTE_PTLOCKS */
-
-struct mm_rss_stat {
- atomic_long_t count[NR_MM_COUNTERS];
-};
-
-struct kioctx_table;
-struct mm_struct {
- struct vm_area_struct *mmap; /* list of VMAs */
- struct rb_root mm_rb;
- u32 vmacache_seqnum; /* per-thread vmacache */
-#ifdef CONFIG_MMU
- unsigned long (*get_unmapped_area) (struct file *filp,
- unsigned long addr, unsigned long len,
- unsigned long pgoff, unsigned long flags);
-#endif
- unsigned long mmap_base; /* base of mmap area */
- unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */
- unsigned long task_size; /* size of task vm space */
- unsigned long highest_vm_end; /* highest vma end address */
- pgd_t * pgd;
- atomic_t mm_users; /* How many users with user space? */
- atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
- atomic_long_t nr_ptes; /* PTE page table pages */
- atomic_long_t nr_pmds; /* PMD page table pages */
- int map_count; /* number of VMAs */
-
- spinlock_t page_table_lock; /* Protects page tables and some counters */
- struct rw_semaphore mmap_sem;
-
- struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
- * together off init_mm.mmlist, and are protected
- * by mmlist_lock
- */
-
-
- unsigned long hiwater_rss; /* High-watermark of RSS usage */
- unsigned long hiwater_vm; /* High-water virtual memory usage */
-
- unsigned long total_vm; /* Total pages mapped */
- unsigned long locked_vm; /* Pages that have PG_mlocked set */
- unsigned long pinned_vm; /* Refcount permanently increased */
- unsigned long shared_vm; /* Shared pages (files) */
- unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE */
- unsigned long stack_vm; /* VM_GROWSUP/DOWN */
- unsigned long def_flags;
- unsigned long start_code, end_code, start_data, end_data;
- unsigned long start_brk, brk, start_stack;
- unsigned long arg_start, arg_end, env_start, env_end;
-
- unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
-
- /*
- * Special counters, in some configurations protected by the
- * page_table_lock, in other configurations by being atomic.
- */
- struct mm_rss_stat rss_stat;
-
- struct linux_binfmt *binfmt;
-
- cpumask_var_t cpu_vm_mask_var;
-
- /* Architecture-specific MM context */
- mm_context_t context;
-
- unsigned long flags; /* Must use atomic bitops to access the bits */
-
- struct core_state *core_state; /* coredumping support */
-#ifdef CONFIG_AIO
- spinlock_t ioctx_lock;
- struct kioctx_table __rcu *ioctx_table;
-#endif
-#ifdef CONFIG_MEMCG
- /*
- * "owner" points to a task that is regarded as the canonical
- * user/owner of this mm. All of the following must be true in
- * order for it to be changed:
- *
- * current == mm->owner
- * current->mm != mm
- * new_owner->mm == mm
- * new_owner->alloc_lock is held
- */
- struct task_struct __rcu *owner;
-#endif
-
- /* store ref to file /proc/<pid>/exe symlink points to */
- struct file *exe_file;
-#ifdef CONFIG_MMU_NOTIFIER
- struct mmu_notifier_mm *mmu_notifier_mm;
-#endif
-#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
- pgtable_t pmd_huge_pte; /* protected by page_table_lock */
-#endif
-#ifdef CONFIG_CPUMASK_OFFSTACK
- struct cpumask cpumask_allocation;
-#endif
-#ifdef CONFIG_NUMA_BALANCING
- /*
- * numa_next_scan is the next time that the PTEs will be marked
- * pte_numa. NUMA hinting faults will gather statistics and migrate
- * pages to new nodes if necessary.
- */
- unsigned long numa_next_scan;
-
- /* Restart point for scanning and setting pte_numa */
- unsigned long numa_scan_offset;
-
- /* numa_scan_seq prevents two threads setting pte_numa */
- int numa_scan_seq;
-#endif
-#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
- /*
- * An operation with batched TLB flushing is going on. Anything that
- * can move process memory needs to flush the TLB when moving a
- * PROT_NONE or PROT_NUMA mapped page.
- */
- bool tlb_flush_pending;
-#endif
- struct uprobes_state uprobes_state;
-#ifdef CONFIG_X86_INTEL_MPX
- /* address of the bounds directory */
- void __user *bd_addr;
-#endif
-};
-
-static inline void mm_init_cpumask(struct mm_struct *mm)
-{
-#ifdef CONFIG_CPUMASK_OFFSTACK
- mm->cpu_vm_mask_var = &mm->cpumask_allocation;
-#endif
- cpumask_clear(mm->cpu_vm_mask_var);
-}
-
-/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
-static inline cpumask_t *mm_cpumask(struct mm_struct *mm)
-{
- return mm->cpu_vm_mask_var;
-}
-
-#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
-/*
- * Memory barriers to keep this state in sync are graciously provided by
- * the page table locks, outside of which no page table modifications happen.
- * The barriers below prevent the compiler from re-ordering the instructions
- * around the memory barriers that are already present in the code.
- */
-static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
-{
- barrier();
- return mm->tlb_flush_pending;
-}
-static inline void set_tlb_flush_pending(struct mm_struct *mm)
-{
- mm->tlb_flush_pending = true;
-
- /*
- * Guarantee that the tlb_flush_pending store does not leak into the
- * critical section updating the page tables
- */
- smp_mb__before_spinlock();
-}
-/* Clearing is done after a TLB flush, which also provides a barrier. */
-static inline void clear_tlb_flush_pending(struct mm_struct *mm)
-{
- barrier();
- mm->tlb_flush_pending = false;
-}
-#else
-static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
-{
- return false;
-}
-static inline void set_tlb_flush_pending(struct mm_struct *mm)
-{
-}
-static inline void clear_tlb_flush_pending(struct mm_struct *mm)
-{
-}
-#endif
-
-struct vm_special_mapping
-{
+struct vm_special_mapping {
const char *name;
struct page **pages;
};
diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index 95243d28a0ee..779e32567e6d 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -4,6 +4,7 @@
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/srcu.h>
struct mmu_notifier;
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 22ee0d5d7f8c..99001775ffa0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -25,6 +25,7 @@ struct sched_param {
#include <linux/errno.h>
#include <linux/nodemask.h>
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/preempt_mask.h>
#include <asm/page.h>
diff --git a/mm/init-mm.c b/mm/init-mm.c
index a56a851908d2..310ae8c7d9c6 100644
--- a/mm/init-mm.c
+++ b/mm/init-mm.c
@@ -1,4 +1,5 @@
#include <linux/mm_types.h>
+#include <linux/mm_struct.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/spinlock.h>
diff --git a/mm/kmemcheck.c b/mm/kmemcheck.c
index cab58bb592d8..c40d065013d2 100644
--- a/mm/kmemcheck.c
+++ b/mm/kmemcheck.c
@@ -1,5 +1,4 @@
#include <linux/gfp.h>
-#include <linux/mm_types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include "slab.h"
--
2.1.4
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