include/linux/mm_types_task.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_MM_TYPES_TASK_H
   3 #define _LINUX_MM_TYPES_TASK_H
   4
   5 /*
   6  * Here are the definitions of the MM data types that are embedded in 'struct task_struct'.
   7  *
   8  * (These are defined separately to decouple sched.h from mm_types.h as much as possible.)
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/threads.h>
  13 #include <linux/atomic.h>
  14 #include <linux/cpumask.h>
  15
  16 #include <asm/page.h>
  17
  18 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
  19 #include <asm/tlbbatch.h>
  20 #endif
  21
  22 #define USE_SPLIT_PTE_PTLOCKS   (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
  23 #define USE_SPLIT_PMD_PTLOCKS   (USE_SPLIT_PTE_PTLOCKS && \
  24                 IS_ENABLED(CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK))
  25 #define ALLOC_SPLIT_PTLOCKS     (SPINLOCK_SIZE > BITS_PER_LONG/8)
  26
  27 /*
  28  * The per task VMA cache array:
  29  */
  30 #define VMACACHE_BITS 2
  31 #define VMACACHE_SIZE (1U << VMACACHE_BITS)
  32 #define VMACACHE_MASK (VMACACHE_SIZE - 1)
  33
  34 struct vmacache {
  35         u64 seqnum;
  36         struct vm_area_struct *vmas[VMACACHE_SIZE];
  37 };
  38
  39 enum {
  40         MM_FILEPAGES,   /* Resident file mapping pages */
  41         MM_ANONPAGES,   /* Resident anonymous pages */
  42         MM_SWAPENTS,    /* Anonymous swap entries */
  43         MM_SHMEMPAGES,  /* Resident shared memory pages */
  44         NR_MM_COUNTERS
  45 };
  46
  47 #if USE_SPLIT_PTE_PTLOCKS && defined(CONFIG_MMU)
  48 #define SPLIT_RSS_COUNTING
  49 /* per-thread cached information, */
  50 struct task_rss_stat {
  51         int events;     /* for synchronization threshold */
  52         int count[NR_MM_COUNTERS];
  53 };
  54 #endif /* USE_SPLIT_PTE_PTLOCKS */
  55
  56 struct mm_rss_stat {
  57         atomic_long_t count[NR_MM_COUNTERS];
  58 };
  59
  60 struct page_frag {
  61         struct page *page;
  62 #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
  63         __u32 offset;
  64         __u32 size;
  65 #else
  66         __u16 offset;
  67         __u16 size;
  68 #endif
  69 };
  70
  71 /* Track pages that require TLB flushes */
  72 struct tlbflush_unmap_batch {
  73 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
  74         /*
  75          * The arch code makes the following promise: generic code can modify a
  76          * PTE, then call arch_tlbbatch_add_mm() (which internally provides all
  77          * needed barriers), then call arch_tlbbatch_flush(), and the entries
  78          * will be flushed on all CPUs by the time that arch_tlbbatch_flush()
  79          * returns.
  80          */
  81         struct arch_tlbflush_unmap_batch arch;
  82
  83         /* True if a flush is needed. */
  84         bool flush_required;
  85
  86         /*
  87          * If true then the PTE was dirty when unmapped. The entry must be
  88          * flushed before IO is initiated or a stale TLB entry potentially
  89          * allows an update without redirtying the page.
  90          */
  91         bool writable;
  92 #endif
  93 };
  94
  95 #endif /* _LINUX_MM_TYPES_TASK_H */