4 files changed, 157 insertions, 27 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 6ad76bf5fb40..a43223af98b6 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -33,13 +33,10 @@
  *      BSS_SECTION(0, 0, 0)
  *      _end = .;
  *
- *      /DISCARD/ : {
- *              EXIT_TEXT
- *              EXIT_DATA
- *              EXIT_CALL
- *      }
  *      STABS_DEBUG
  *      DWARF_DEBUG
+ *
+ *      DISCARDS                // must be the last
  * }
  *
  * [__init_begin, __init_end] is the init section that may be freed after init
@@ -626,6 +623,23 @@
 #define INIT_RAM_FS
 #endif
 
+/*
+ * Default discarded sections.
+ *
+ * Some archs want to discard exit text/data at runtime rather than
+ * link time due to cross-section references such as alt instructions,
+ * bug table, eh_frame, etc.  DISCARDS must be the last of output
+ * section definitions so that such archs put those in earlier section
+ * definitions.
+ */
+#define DISCARDS                                                        \
+        /DISCARD/ : {                                                   \
+        EXIT_TEXT                                                       \
+        EXIT_DATA                                                       \
+        EXIT_CALL                                                       \
+        *(.discard)                                                     \
+        }
+
 /**
  * PERCPU_VADDR - define output section for percpu area
  * @vaddr: explicit base address (optional)
diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h
index 0761491b3eec..9bd03193ecd4 100644
--- a/include/linux/percpu-defs.h
+++ b/include/linux/percpu-defs.h
@@ -10,22 +10,70 @@
 /*
  * Base implementations of per-CPU variable declarations and definitions, where
  * the section in which the variable is to be placed is provided by the
- * 'section' argument.  This may be used to affect the parameters governing the
+ * 'sec' argument.  This may be used to affect the parameters governing the
  * variable's storage.
  *
  * NOTE!  The sections for the DECLARE and for the DEFINE must match, lest
  * linkage errors occur due the compiler generating the wrong code to access
  * that section.
  */
-#define DECLARE_PER_CPU_SECTION(type, name, section)                    \
-        extern                                                          \
-        __attribute__((__section__(PER_CPU_BASE_SECTION section)))      \
-        PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
-
-#define DEFINE_PER_CPU_SECTION(type, name, section)                     \
-        __attribute__((__section__(PER_CPU_BASE_SECTION section)))      \
-        PER_CPU_ATTRIBUTES PER_CPU_DEF_ATTRIBUTES                       \
+#define __PCPU_ATTRS(sec)                                               \
+        __attribute__((section(PER_CPU_BASE_SECTION sec)))              \
+        PER_CPU_ATTRIBUTES
+
+#define __PCPU_DUMMY_ATTRS                                              \
+        __attribute__((section(".discard"), unused))
+
+/*
+ * s390 and alpha modules require percpu variables to be defined as
+ * weak to force the compiler to generate GOT based external
+ * references for them.  This is necessary because percpu sections
+ * will be located outside of the usually addressable area.
+ *
+ * This definition puts the following two extra restrictions when
+ * defining percpu variables.
+ *
+ * 1. The symbol must be globally unique, even the static ones.
+ * 2. Static percpu variables cannot be defined inside a function.
+ *
+ * Archs which need weak percpu definitions should define
+ * ARCH_NEEDS_WEAK_PER_CPU in asm/percpu.h when necessary.
+ *
+ * To ensure that the generic code observes the above two
+ * restrictions, if CONFIG_DEBUG_FORCE_WEAK_PER_CPU is set weak
+ * definition is used for all cases.
+ */
+#if defined(ARCH_NEEDS_WEAK_PER_CPU) || defined(CONFIG_DEBUG_FORCE_WEAK_PER_CPU)
+/*
+ * __pcpu_scope_* dummy variable is used to enforce scope.  It
+ * receives the static modifier when it's used in front of
+ * DEFINE_PER_CPU() and will trigger build failure if
+ * DECLARE_PER_CPU() is used for the same variable.
+ *
+ * __pcpu_unique_* dummy variable is used to enforce symbol uniqueness
+ * such that hidden weak symbol collision, which will cause unrelated
+ * variables to share the same address, can be detected during build.
+ */
+#define DECLARE_PER_CPU_SECTION(type, name, sec)                        \
+        extern __PCPU_DUMMY_ATTRS char __pcpu_scope_##name;             \
+        extern __PCPU_ATTRS(sec) __typeof__(type) per_cpu__##name
+
+#define DEFINE_PER_CPU_SECTION(type, name, sec)                         \
+        __PCPU_DUMMY_ATTRS char __pcpu_scope_##name;                    \
+        __PCPU_DUMMY_ATTRS char __pcpu_unique_##name;                   \
+        __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES __weak                 \
+        __typeof__(type) per_cpu__##name
+#else
+/*
+ * Normal declaration and definition macros.
+ */
+#define DECLARE_PER_CPU_SECTION(type, name, sec)                        \
+        extern __PCPU_ATTRS(sec) __typeof__(type) per_cpu__##name
+
+#define DEFINE_PER_CPU_SECTION(type, name, sec)                         \
+        __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES                        \
         __typeof__(type) per_cpu__##name
+#endif
 
 /*
  * Variant on the per-CPU variable declaration/definition theme used for
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 26fd9d12f050..878836ca999c 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -34,7 +34,7 @@
 
 #ifdef CONFIG_SMP
 
-#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
+#ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA
 
 /* minimum unit size, also is the maximum supported allocation size */
 #define PCPU_MIN_UNIT_SIZE              PFN_ALIGN(64 << 10)
@@ -57,19 +57,70 @@
 #endif
 
 extern void *pcpu_base_addr;
+extern const unsigned long *pcpu_unit_offsets;
 
-typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno);
-typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr);
+struct pcpu_group_info {
+        int                     nr_units;       /* aligned # of units */
+        unsigned long           base_offset;    /* base address offset */
+        unsigned int            *cpu_map;       /* unit->cpu map, empty
+                                                 * entries contain NR_CPUS */
+};
+
+struct pcpu_alloc_info {
+        size_t                  static_size;
+        size_t                  reserved_size;
+        size_t                  dyn_size;
+        size_t                  unit_size;
+        size_t                  atom_size;
+        size_t                  alloc_size;
+        size_t                  __ai_size;      /* internal, don't use */
+        int                     nr_groups;      /* 0 if grouping unnecessary */
+        struct pcpu_group_info  groups[];
+};
 
-extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn,
-                                size_t static_size, size_t reserved_size,
-                                ssize_t dyn_size, ssize_t unit_size,
-                                void *base_addr,
-                                pcpu_populate_pte_fn_t populate_pte_fn);
+enum pcpu_fc {
+        PCPU_FC_AUTO,
+        PCPU_FC_EMBED,
+        PCPU_FC_PAGE,
 
-extern ssize_t __init pcpu_embed_first_chunk(
-                                size_t static_size, size_t reserved_size,
-                                ssize_t dyn_size, ssize_t unit_size);
+        PCPU_FC_NR,
+};
+extern const char *pcpu_fc_names[PCPU_FC_NR];
+
+extern enum pcpu_fc pcpu_chosen_fc;
+
+typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
+                                     size_t align);
+typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
+typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
+typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
+
+extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
+                                                             int nr_units);
+extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
+
+extern struct pcpu_alloc_info * __init pcpu_build_alloc_info(
+                                size_t reserved_size, ssize_t dyn_size,
+                                size_t atom_size,
+                                pcpu_fc_cpu_distance_fn_t cpu_distance_fn);
+
+extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
+                                         void *base_addr);
+
+#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
+extern int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size,
+                                size_t atom_size,
+                                pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
+                                pcpu_fc_alloc_fn_t alloc_fn,
+                                pcpu_fc_free_fn_t free_fn);
+#endif
+
+#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
+extern int __init pcpu_page_first_chunk(size_t reserved_size,
+                                pcpu_fc_alloc_fn_t alloc_fn,
+                                pcpu_fc_free_fn_t free_fn,
+                                pcpu_fc_populate_pte_fn_t populate_pte_fn);
+#endif
 
 /*
  * Use this to get to a cpu's version of the per-cpu object
@@ -80,7 +131,7 @@ extern ssize_t __init pcpu_embed_first_chunk(
 
 extern void *__alloc_reserved_percpu(size_t size, size_t align);
 
-#else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
+#else /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */
 
 struct percpu_data {
         void *ptrs[1];
@@ -99,11 +150,15 @@ struct percpu_data {
         (__typeof__(ptr))__p->ptrs[(cpu)];                              \
 })
 
-#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
+#endif /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */
 
 extern void *__alloc_percpu(size_t size, size_t align);
 extern void free_percpu(void *__pdata);
 
+#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
+extern void __init setup_per_cpu_areas(void);
+#endif
+
 #else /* CONFIG_SMP */
 
 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
@@ -124,6 +179,13 @@ static inline void free_percpu(void *p)
         kfree(p);
 }
 
+static inline void __init setup_per_cpu_areas(void) { }
+
+static inline void *pcpu_lpage_remapped(void *kaddr)
+{
+        return NULL;
+}
+
 #endif /* CONFIG_SMP */
 
 #define alloc_percpu(type)      (type *)__alloc_percpu(sizeof(type), \
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index a43ebec3a7b9..227c2a585e4f 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -115,4 +115,10 @@ extern rwlock_t vmlist_lock;
 extern struct vm_struct *vmlist;
 extern __init void vm_area_register_early(struct vm_struct *vm, size_t align);
 
+struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
+                                     const size_t *sizes, int nr_vms,
+                                     size_t align, gfp_t gfp_mask);
+
+void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms);
+
 #endif /* _LINUX_VMALLOC_H */