Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Tested-by: SeongJae Park <sj@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> --- MAINTAINERS | 1 + tools/testing/shared/shared.mk | 3 + tools/testing/vma/.gitignore | 7 + tools/testing/vma/Makefile | 16 + tools/testing/vma/linux/atomic.h | 12 + tools/testing/vma/linux/mmzone.h | 38 ++ tools/testing/vma/vma.c | 207 ++++++++ tools/testing/vma/vma_internal.h | 882 +++++++++++++++++++++++++++++++ 8 files changed, 1166 insertions(+) create mode 100644 tools/testing/vma/.gitignore create mode 100644 tools/testing/vma/Makefile create mode 100644 tools/testing/vma/linux/atomic.h create mode 100644 tools/testing/vma/linux/mmzone.h create mode 100644 tools/testing/vma/vma.c create mode 100644 tools/testing/vma/vma_internal.h diff --git a/MAINTAINERS b/MAINTAINERS index 5d39702afa4a..8bab2f641fdf 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -24331,6 +24331,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm F: mm/vma.c F: mm/vma.h F: mm/vma_internal.h +F: tools/testing/vma/ VMALLOC M: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> diff --git a/tools/testing/shared/shared.mk b/tools/testing/shared/shared.mk index 6b0226400ed0..f5d68a9a36df 100644 --- a/tools/testing/shared/shared.mk +++ b/tools/testing/shared/shared.mk @@ -50,9 +50,11 @@ maple-shared.o: ../shared/maple-shared.c ../../../lib/maple_tree.c \ ../../../lib/test_maple_tree.c generated/autoconf.h: + @mkdir -p generated cp ../shared/autoconf.h generated/autoconf.h generated/map-shift.h: + @mkdir -p generated @if ! grep -qws $(SHIFT) generated/map-shift.h; then \ echo "Generating $@"; \ echo "#define XA_CHUNK_SHIFT $(SHIFT)" > \ @@ -60,6 +62,7 @@ generated/map-shift.h: fi generated/bit-length.h: FORCE + @mkdir -p generated @if ! grep -qws CONFIG_$(LONG_BIT)BIT generated/bit-length.h; then \ echo "Generating $@"; \ echo "#define CONFIG_$(LONG_BIT)BIT 1" > $@; \ diff --git a/tools/testing/vma/.gitignore b/tools/testing/vma/.gitignore new file mode 100644 index 000000000000..b003258eba79 --- /dev/null +++ b/tools/testing/vma/.gitignore @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0-only +generated/bit-length.h +generated/map-shift.h +generated/autoconf.h +idr.c +radix-tree.c +vma diff --git a/tools/testing/vma/Makefile b/tools/testing/vma/Makefile new file mode 100644 index 000000000000..bfc905d222cf --- /dev/null +++ b/tools/testing/vma/Makefile @@ -0,0 +1,16 @@ +# SPDX-License-Identifier: GPL-2.0-or-later + +.PHONY: default + +default: vma + +include ../shared/shared.mk + +OFILES = $(SHARED_OFILES) vma.o maple-shim.o +TARGETS = vma + +vma: $(OFILES) vma_internal.h ../../../mm/vma.c ../../../mm/vma.h + $(CC) $(CFLAGS) -o $@ $(OFILES) $(LDLIBS) + +clean: + $(RM) $(TARGETS) *.o radix-tree.c idr.c generated/map-shift.h generated/bit-length.h generated/autoconf.h diff --git a/tools/testing/vma/linux/atomic.h b/tools/testing/vma/linux/atomic.h new file mode 100644 index 000000000000..e01f66f98982 --- /dev/null +++ b/tools/testing/vma/linux/atomic.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _LINUX_ATOMIC_H +#define _LINUX_ATOMIC_H + +#define atomic_t int32_t +#define atomic_inc(x) uatomic_inc(x) +#define atomic_read(x) uatomic_read(x) +#define atomic_set(x, y) do {} while (0) +#define U8_MAX UCHAR_MAX + +#endif /* _LINUX_ATOMIC_H */ diff --git a/tools/testing/vma/linux/mmzone.h b/tools/testing/vma/linux/mmzone.h new file mode 100644 index 000000000000..33cd1517f7a3 --- /dev/null +++ b/tools/testing/vma/linux/mmzone.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _LINUX_MMZONE_H +#define _LINUX_MMZONE_H + +#include <linux/atomic.h> + +struct pglist_data *first_online_pgdat(void); +struct pglist_data *next_online_pgdat(struct pglist_data *pgdat); + +#define for_each_online_pgdat(pgdat) \ + for (pgdat = first_online_pgdat(); \ + pgdat; \ + pgdat = next_online_pgdat(pgdat)) + +enum zone_type { + __MAX_NR_ZONES +}; + +#define MAX_NR_ZONES __MAX_NR_ZONES +#define MAX_PAGE_ORDER 10 +#define MAX_ORDER_NR_PAGES (1 << MAX_PAGE_ORDER) + +#define pageblock_order MAX_PAGE_ORDER +#define pageblock_nr_pages BIT(pageblock_order) +#define pageblock_align(pfn) ALIGN((pfn), pageblock_nr_pages) +#define pageblock_start_pfn(pfn) ALIGN_DOWN((pfn), pageblock_nr_pages) + +struct zone { + atomic_long_t managed_pages; +}; + +typedef struct pglist_data { + struct zone node_zones[MAX_NR_ZONES]; + +} pg_data_t; + +#endif /* _LINUX_MMZONE_H */ diff --git a/tools/testing/vma/vma.c b/tools/testing/vma/vma.c new file mode 100644 index 000000000000..48e033c60d87 --- /dev/null +++ b/tools/testing/vma/vma.c @@ -0,0 +1,207 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> + +#include "maple-shared.h" +#include "vma_internal.h" + +/* + * Directly import the VMA implementation here. Our vma_internal.h wrapper + * provides userland-equivalent functionality for everything vma.c uses. + */ +#include "../../../mm/vma.c" + +const struct vm_operations_struct vma_dummy_vm_ops; + +#define ASSERT_TRUE(_expr) \ + do { \ + if (!(_expr)) { \ + fprintf(stderr, \ + "Assert FAILED at %s:%d:%s(): %s is FALSE.\n", \ + __FILE__, __LINE__, __FUNCTION__, #_expr); \ + return false; \ + } \ + } while (0) +#define ASSERT_FALSE(_expr) ASSERT_TRUE(!(_expr)) +#define ASSERT_EQ(_val1, _val2) ASSERT_TRUE((_val1) == (_val2)) +#define ASSERT_NE(_val1, _val2) ASSERT_TRUE((_val1) != (_val2)) + +static struct vm_area_struct *alloc_vma(struct mm_struct *mm, + unsigned long start, + unsigned long end, + pgoff_t pgoff, + vm_flags_t flags) +{ + struct vm_area_struct *ret = vm_area_alloc(mm); + + if (ret == NULL) + return NULL; + + ret->vm_start = start; + ret->vm_end = end; + ret->vm_pgoff = pgoff; + ret->__vm_flags = flags; + + return ret; +} + +static bool test_simple_merge(void) +{ + struct vm_area_struct *vma; + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *vma_left = alloc_vma(&mm, 0, 0x1000, 0, flags); + struct vm_area_struct *vma_middle = alloc_vma(&mm, 0x1000, 0x2000, 1, flags); + struct vm_area_struct *vma_right = alloc_vma(&mm, 0x2000, 0x3000, 2, flags); + VMA_ITERATOR(vmi, &mm, 0x1000); + + ASSERT_FALSE(vma_link(&mm, vma_left)); + ASSERT_FALSE(vma_link(&mm, vma_middle)); + ASSERT_FALSE(vma_link(&mm, vma_right)); + + vma = vma_merge_new_vma(&vmi, vma_left, vma_middle, 0x1000, + 0x2000, 1); + ASSERT_NE(vma, NULL); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->vm_flags, flags); + + vm_area_free(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_simple_modify(void) +{ + struct vm_area_struct *vma; + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *init_vma = alloc_vma(&mm, 0, 0x3000, 0, flags); + VMA_ITERATOR(vmi, &mm, 0x1000); + + ASSERT_FALSE(vma_link(&mm, init_vma)); + + /* + * The flags will not be changed, the vma_modify_flags() function + * performs the merge/split only. + */ + vma = vma_modify_flags(&vmi, init_vma, init_vma, + 0x1000, 0x2000, VM_READ | VM_MAYREAD); + ASSERT_NE(vma, NULL); + /* We modify the provided VMA, and on split allocate new VMAs. */ + ASSERT_EQ(vma, init_vma); + + ASSERT_EQ(vma->vm_start, 0x1000); + ASSERT_EQ(vma->vm_end, 0x2000); + ASSERT_EQ(vma->vm_pgoff, 1); + + /* + * Now walk through the three split VMAs and make sure they are as + * expected. + */ + + vma_iter_set(&vmi, 0); + vma = vma_iter_load(&vmi); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x1000); + ASSERT_EQ(vma->vm_pgoff, 0); + + vm_area_free(vma); + vma_iter_clear(&vmi); + + vma = vma_next(&vmi); + + ASSERT_EQ(vma->vm_start, 0x1000); + ASSERT_EQ(vma->vm_end, 0x2000); + ASSERT_EQ(vma->vm_pgoff, 1); + + vm_area_free(vma); + vma_iter_clear(&vmi); + + vma = vma_next(&vmi); + + ASSERT_EQ(vma->vm_start, 0x2000); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 2); + + vm_area_free(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_simple_expand(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *vma = alloc_vma(&mm, 0, 0x1000, 0, flags); + VMA_ITERATOR(vmi, &mm, 0); + + ASSERT_FALSE(vma_link(&mm, vma)); + + ASSERT_FALSE(vma_expand(&vmi, vma, 0, 0x3000, 0, NULL)); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 0); + + vm_area_free(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_simple_shrink(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *vma = alloc_vma(&mm, 0, 0x3000, 0, flags); + VMA_ITERATOR(vmi, &mm, 0); + + ASSERT_FALSE(vma_link(&mm, vma)); + + ASSERT_FALSE(vma_shrink(&vmi, vma, 0, 0x1000, 0)); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x1000); + ASSERT_EQ(vma->vm_pgoff, 0); + + vm_area_free(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +int main(void) +{ + int num_tests = 0, num_fail = 0; + + maple_tree_init(); + +#define TEST(name) \ + do { \ + num_tests++; \ + if (!test_##name()) { \ + num_fail++; \ + fprintf(stderr, "Test " #name " FAILED\n"); \ + } \ + } while (0) + + TEST(simple_merge); + TEST(simple_modify); + TEST(simple_expand); + TEST(simple_shrink); + +#undef TEST + + printf("%d tests run, %d passed, %d failed.\n", + num_tests, num_tests - num_fail, num_fail); + + return num_fail == 0 ? EXIT_SUCCESS : EXIT_FAILURE; +} diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h new file mode 100644 index 000000000000..093560e5b2ac --- /dev/null +++ b/tools/testing/vma/vma_internal.h @@ -0,0 +1,882 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * vma_internal.h + * + * Header providing userland wrappers and shims for the functionality provided + * by mm/vma_internal.h. + * + * We make the header guard the same as mm/vma_internal.h, so if this shim + * header is included, it precludes the inclusion of the kernel one. + */ + +#ifndef __MM_VMA_INTERNAL_H +#define __MM_VMA_INTERNAL_H + +#define __private +#define __bitwise +#define __randomize_layout + +#define CONFIG_MMU +#define CONFIG_PER_VMA_LOCK + +#include <stdlib.h> + +#include <linux/list.h> +#include <linux/maple_tree.h> +#include <linux/mm.h> +#include <linux/rbtree.h> +#include <linux/rwsem.h> + +#define VM_WARN_ON(_expr) (WARN_ON(_expr)) +#define VM_WARN_ON_ONCE(_expr) (WARN_ON_ONCE(_expr)) +#define VM_BUG_ON(_expr) (BUG_ON(_expr)) +#define VM_BUG_ON_VMA(_expr, _vma) (BUG_ON(_expr)) + +#define VM_NONE 0x00000000 +#define VM_READ 0x00000001 +#define VM_WRITE 0x00000002 +#define VM_EXEC 0x00000004 +#define VM_SHARED 0x00000008 +#define VM_MAYREAD 0x00000010 +#define VM_MAYWRITE 0x00000020 +#define VM_GROWSDOWN 0x00000100 +#define VM_PFNMAP 0x00000400 +#define VM_LOCKED 0x00002000 +#define VM_IO 0x00004000 +#define VM_DONTEXPAND 0x00040000 +#define VM_ACCOUNT 0x00100000 +#define VM_MIXEDMAP 0x10000000 +#define VM_STACK VM_GROWSDOWN +#define VM_SHADOW_STACK VM_NONE +#define VM_SOFTDIRTY 0 + +#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC) +#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) + +#define FIRST_USER_ADDRESS 0UL +#define USER_PGTABLES_CEILING 0UL + +#define vma_policy(vma) NULL + +#define down_write_nest_lock(sem, nest_lock) + +#define pgprot_val(x) ((x).pgprot) +#define __pgprot(x) ((pgprot_t) { (x) } ) + +#define for_each_vma(__vmi, __vma) \ + while (((__vma) = vma_next(&(__vmi))) != NULL) + +/* The MM code likes to work with exclusive end addresses */ +#define for_each_vma_range(__vmi, __vma, __end) \ + while (((__vma) = vma_find(&(__vmi), (__end))) != NULL) + +#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) + +#define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT)) + +#define test_and_set_bit(nr, addr) __test_and_set_bit(nr, addr) +#define test_and_clear_bit(nr, addr) __test_and_clear_bit(nr, addr) + +#define TASK_SIZE ((1ul << 47)-PAGE_SIZE) + +#define AS_MM_ALL_LOCKS 2 + +#define current NULL + +/* We hardcode this for now. */ +#define sysctl_max_map_count 0x1000000UL + +#define pgoff_t unsigned long +typedef unsigned long pgprotval_t; +typedef struct pgprot { pgprotval_t pgprot; } pgprot_t; +typedef unsigned long vm_flags_t; +typedef __bitwise unsigned int vm_fault_t; + +typedef struct refcount_struct { + atomic_t refs; +} refcount_t; + +struct kref { + refcount_t refcount; +}; + +struct anon_vma { + struct anon_vma *root; + struct rb_root_cached rb_root; +}; + +struct anon_vma_chain { + struct anon_vma *anon_vma; + struct list_head same_vma; +}; + +struct anon_vma_name { + struct kref kref; + /* The name needs to be at the end because it is dynamically sized. */ + char name[]; +}; + +struct vma_iterator { + struct ma_state mas; +}; + +#define VMA_ITERATOR(name, __mm, __addr) \ + struct vma_iterator name = { \ + .mas = { \ + .tree = &(__mm)->mm_mt, \ + .index = __addr, \ + .node = NULL, \ + .status = ma_start, \ + }, \ + } + +struct address_space { + struct rb_root_cached i_mmap; + unsigned long flags; + atomic_t i_mmap_writable; +}; + +struct vm_userfaultfd_ctx {}; +struct mempolicy {}; +struct mmu_gather {}; +struct mutex {}; +#define DEFINE_MUTEX(mutexname) \ + struct mutex mutexname = {} + +struct mm_struct { + struct maple_tree mm_mt; + int map_count; /* number of VMAs */ + unsigned long total_vm; /* Total pages mapped */ + unsigned long locked_vm; /* Pages that have PG_mlocked set */ + unsigned long data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */ + unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */ + unsigned long stack_vm; /* VM_STACK */ +}; + +struct vma_lock { + struct rw_semaphore lock; +}; + + +struct file { + struct address_space *f_mapping; +}; + +struct vm_area_struct { + /* The first cache line has the info for VMA tree walking. */ + + union { + struct { + /* VMA covers [vm_start; vm_end) addresses within mm */ + unsigned long vm_start; + unsigned long vm_end; + }; +#ifdef CONFIG_PER_VMA_LOCK + struct rcu_head vm_rcu; /* Used for deferred freeing. */ +#endif + }; + + struct mm_struct *vm_mm; /* The address space we belong to. */ + pgprot_t vm_page_prot; /* Access permissions of this VMA. */ + + /* + * Flags, see mm.h. + * To modify use vm_flags_{init|reset|set|clear|mod} functions. + */ + union { + const vm_flags_t vm_flags; + vm_flags_t __private __vm_flags; + }; + +#ifdef CONFIG_PER_VMA_LOCK + /* Flag to indicate areas detached from the mm->mm_mt tree */ + bool detached; + + /* + * Can only be written (using WRITE_ONCE()) while holding both: + * - mmap_lock (in write mode) + * - vm_lock->lock (in write mode) + * Can be read reliably while holding one of: + * - mmap_lock (in read or write mode) + * - vm_lock->lock (in read or write mode) + * Can be read unreliably (using READ_ONCE()) for pessimistic bailout + * while holding nothing (except RCU to keep the VMA struct allocated). + * + * This sequence counter is explicitly allowed to overflow; sequence + * counter reuse can only lead to occasional unnecessary use of the + * slowpath. + */ + int vm_lock_seq; + struct vma_lock *vm_lock; +#endif + + /* + * For areas with an address space and backing store, + * linkage into the address_space->i_mmap interval tree. + * + */ + struct { + struct rb_node rb; + unsigned long rb_subtree_last; + } shared; + + /* + * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma + * list, after a COW of one of the file pages. A MAP_SHARED vma + * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack + * or brk vma (with NULL file) can only be in an anon_vma list. + */ + struct list_head anon_vma_chain; /* Serialized by mmap_lock & + * page_table_lock */ + struct anon_vma *anon_vma; /* Serialized by page_table_lock */ + + /* Function pointers to deal with this struct. */ + const struct vm_operations_struct *vm_ops; + + /* Information about our backing store: */ + unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE + units */ + struct file * vm_file; /* File we map to (can be NULL). */ + void * vm_private_data; /* was vm_pte (shared mem) */ + +#ifdef CONFIG_ANON_VMA_NAME + /* + * For private and shared anonymous mappings, a pointer to a null + * terminated string containing the name given to the vma, or NULL if + * unnamed. Serialized by mmap_lock. Use anon_vma_name to access. + */ + struct anon_vma_name *anon_name; +#endif +#ifdef CONFIG_SWAP + atomic_long_t swap_readahead_info; +#endif +#ifndef CONFIG_MMU + struct vm_region *vm_region; /* NOMMU mapping region */ +#endif +#ifdef CONFIG_NUMA + struct mempolicy *vm_policy; /* NUMA policy for the VMA */ +#endif +#ifdef CONFIG_NUMA_BALANCING + struct vma_numab_state *numab_state; /* NUMA Balancing state */ +#endif + struct vm_userfaultfd_ctx vm_userfaultfd_ctx; +} __randomize_layout; + +struct vm_fault {}; + +struct vm_operations_struct { + void (*open)(struct vm_area_struct * area); + /** + * @close: Called when the VMA is being removed from the MM. + * Context: User context. May sleep. Caller holds mmap_lock. + */ + void (*close)(struct vm_area_struct * area); + /* Called any time before splitting to check if it's allowed */ + int (*may_split)(struct vm_area_struct *area, unsigned long addr); + int (*mremap)(struct vm_area_struct *area); + /* + * Called by mprotect() to make driver-specific permission + * checks before mprotect() is finalised. The VMA must not + * be modified. Returns 0 if mprotect() can proceed. + */ + int (*mprotect)(struct vm_area_struct *vma, unsigned long start, + unsigned long end, unsigned long newflags); + vm_fault_t (*fault)(struct vm_fault *vmf); + vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order); + vm_fault_t (*map_pages)(struct vm_fault *vmf, + pgoff_t start_pgoff, pgoff_t end_pgoff); + unsigned long (*pagesize)(struct vm_area_struct * area); + + /* notification that a previously read-only page is about to become + * writable, if an error is returned it will cause a SIGBUS */ + vm_fault_t (*page_mkwrite)(struct vm_fault *vmf); + + /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */ + vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf); + + /* called by access_process_vm when get_user_pages() fails, typically + * for use by special VMAs. See also generic_access_phys() for a generic + * implementation useful for any iomem mapping. + */ + int (*access)(struct vm_area_struct *vma, unsigned long addr, + void *buf, int len, int write); + + /* Called by the /proc/PID/maps code to ask the vma whether it + * has a special name. Returning non-NULL will also cause this + * vma to be dumped unconditionally. */ + const char *(*name)(struct vm_area_struct *vma); + +#ifdef CONFIG_NUMA + /* + * set_policy() op must add a reference to any non-NULL @new mempolicy + * to hold the policy upon return. Caller should pass NULL @new to + * remove a policy and fall back to surrounding context--i.e. do not + * install a MPOL_DEFAULT policy, nor the task or system default + * mempolicy. + */ + int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); + + /* + * get_policy() op must add reference [mpol_get()] to any policy at + * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure + * in mm/mempolicy.c will do this automatically. + * get_policy() must NOT add a ref if the policy at (vma,addr) is not + * marked as MPOL_SHARED. vma policies are protected by the mmap_lock. + * If no [shared/vma] mempolicy exists at the addr, get_policy() op + * must return NULL--i.e., do not "fallback" to task or system default + * policy. + */ + struct mempolicy *(*get_policy)(struct vm_area_struct *vma, + unsigned long addr, pgoff_t *ilx); +#endif + /* + * Called by vm_normal_page() for special PTEs to find the + * page for @addr. This is useful if the default behavior + * (using pte_page()) would not find the correct page. + */ + struct page *(*find_special_page)(struct vm_area_struct *vma, + unsigned long addr); +}; + +static inline void vma_iter_invalidate(struct vma_iterator *vmi) +{ + mas_pause(&vmi->mas); +} + +static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) +{ + return __pgprot(pgprot_val(oldprot) | pgprot_val(newprot)); +} + +static inline pgprot_t vm_get_page_prot(unsigned long vm_flags) +{ + return __pgprot(vm_flags); +} + +static inline bool is_shared_maywrite(vm_flags_t vm_flags) +{ + return (vm_flags & (VM_SHARED | VM_MAYWRITE)) == + (VM_SHARED | VM_MAYWRITE); +} + +static inline bool vma_is_shared_maywrite(struct vm_area_struct *vma) +{ + return is_shared_maywrite(vma->vm_flags); +} + +static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi) +{ + /* + * Uses mas_find() to get the first VMA when the iterator starts. + * Calling mas_next() could skip the first entry. + */ + return mas_find(&vmi->mas, ULONG_MAX); +} + +static inline bool vma_lock_alloc(struct vm_area_struct *vma) +{ + vma->vm_lock = calloc(1, sizeof(struct vma_lock)); + + if (!vma->vm_lock) + return false; + + init_rwsem(&vma->vm_lock->lock); + vma->vm_lock_seq = -1; + + return true; +} + +static inline void vma_assert_write_locked(struct vm_area_struct *); +static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached) +{ + /* When detaching vma should be write-locked */ + if (detached) + vma_assert_write_locked(vma); + vma->detached = detached; +} + +extern const struct vm_operations_struct vma_dummy_vm_ops; + +static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) +{ + memset(vma, 0, sizeof(*vma)); + vma->vm_mm = mm; + vma->vm_ops = &vma_dummy_vm_ops; + INIT_LIST_HEAD(&vma->anon_vma_chain); + vma_mark_detached(vma, false); +} + +static inline struct vm_area_struct *vm_area_alloc(struct mm_struct *mm) +{ + struct vm_area_struct *vma = calloc(1, sizeof(struct vm_area_struct)); + + if (!vma) + return NULL; + + vma_init(vma, mm); + if (!vma_lock_alloc(vma)) { + free(vma); + return NULL; + } + + return vma; +} + +static inline struct vm_area_struct *vm_area_dup(struct vm_area_struct *orig) +{ + struct vm_area_struct *new = calloc(1, sizeof(struct vm_area_struct)); + + if (!new) + return NULL; + + memcpy(new, orig, sizeof(*new)); + if (!vma_lock_alloc(new)) { + free(new); + return NULL; + } + INIT_LIST_HEAD(&new->anon_vma_chain); + + return new; +} + +/* + * These are defined in vma.h, but sadly vm_stat_account() is referenced by + * kernel/fork.c, so we have to these broadly available there, and temporarily + * define them here to resolve the dependency cycle. + */ + +#define is_exec_mapping(flags) \ + ((flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC) + +#define is_stack_mapping(flags) \ + (((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK)) + +#define is_data_mapping(flags) \ + ((flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE) + +static inline void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, + long npages) +{ + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm)+npages); + + if (is_exec_mapping(flags)) + mm->exec_vm += npages; + else if (is_stack_mapping(flags)) + mm->stack_vm += npages; + else if (is_data_mapping(flags)) + mm->data_vm += npages; +} + +#undef is_exec_mapping +#undef is_stack_mapping +#undef is_data_mapping + +/* Currently stubbed but we may later wish to un-stub. */ +static inline void vm_acct_memory(long pages); +static inline void vm_unacct_memory(long pages) +{ + vm_acct_memory(-pages); +} + +static inline void mapping_allow_writable(struct address_space *mapping) +{ + atomic_inc(&mapping->i_mmap_writable); +} + +static inline void vma_set_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, + pgoff_t pgoff) +{ + vma->vm_start = start; + vma->vm_end = end; + vma->vm_pgoff = pgoff; +} + +static inline +struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max) +{ + return mas_find(&vmi->mas, max - 1); +} + +static inline int vma_iter_clear_gfp(struct vma_iterator *vmi, + unsigned long start, unsigned long end, gfp_t gfp) +{ + __mas_set_range(&vmi->mas, start, end - 1); + mas_store_gfp(&vmi->mas, NULL, gfp); + if (unlikely(mas_is_err(&vmi->mas))) + return -ENOMEM; + + return 0; +} + +static inline void mmap_assert_locked(struct mm_struct *); +static inline struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, + unsigned long start_addr, + unsigned long end_addr) +{ + unsigned long index = start_addr; + + mmap_assert_locked(mm); + return mt_find(&mm->mm_mt, &index, end_addr - 1); +} + +static inline +struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr) +{ + return mtree_load(&mm->mm_mt, addr); +} + +static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi) +{ + return mas_prev(&vmi->mas, 0); +} + +static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr) +{ + mas_set(&vmi->mas, addr); +} + +static inline bool vma_is_anonymous(struct vm_area_struct *vma) +{ + return !vma->vm_ops; +} + +/* Defined in vma.h, so temporarily define here to avoid circular dependency. */ +#define vma_iter_load(vmi) \ + mas_walk(&(vmi)->mas) + +static inline struct vm_area_struct * +find_vma_prev(struct mm_struct *mm, unsigned long addr, + struct vm_area_struct **pprev) +{ + struct vm_area_struct *vma; + VMA_ITERATOR(vmi, mm, addr); + + vma = vma_iter_load(&vmi); + *pprev = vma_prev(&vmi); + if (!vma) + vma = vma_next(&vmi); + return vma; +} + +#undef vma_iter_load + +static inline void vma_iter_init(struct vma_iterator *vmi, + struct mm_struct *mm, unsigned long addr) +{ + mas_init(&vmi->mas, &mm->mm_mt, addr); +} + +/* Stubbed functions. */ + +static inline struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma) +{ + return NULL; +} + +static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, + struct vm_userfaultfd_ctx vm_ctx) +{ + return true; +} + +static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1, + struct anon_vma_name *anon_name2) +{ + return true; +} + +static inline void might_sleep(void) +{ +} + +static inline unsigned long vma_pages(struct vm_area_struct *vma) +{ + return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; +} + +static inline void fput(struct file *) +{ +} + +static inline void mpol_put(struct mempolicy *) +{ +} + +static inline void vma_lock_free(struct vm_area_struct *vma) +{ + free(vma->vm_lock); +} + +static inline void __vm_area_free(struct vm_area_struct *vma) +{ + vma_lock_free(vma); + free(vma); +} + +static inline void vm_area_free(struct vm_area_struct *vma) +{ + __vm_area_free(vma); +} + +static inline void lru_add_drain(void) +{ +} + +static inline void tlb_gather_mmu(struct mmu_gather *, struct mm_struct *) +{ +} + +static inline void update_hiwater_rss(struct mm_struct *) +{ +} + +static inline void update_hiwater_vm(struct mm_struct *) +{ +} + +static inline void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas, + struct vm_area_struct *vma, unsigned long start_addr, + unsigned long end_addr, unsigned long tree_end, + bool mm_wr_locked) +{ + (void)tlb; + (void)mas; + (void)vma; + (void)start_addr; + (void)end_addr; + (void)tree_end; + (void)mm_wr_locked; +} + +static inline void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, + struct vm_area_struct *vma, unsigned long floor, + unsigned long ceiling, bool mm_wr_locked) +{ + (void)tlb; + (void)mas; + (void)vma; + (void)floor; + (void)ceiling; + (void)mm_wr_locked; +} + +static inline void mapping_unmap_writable(struct address_space *) +{ +} + +static inline void flush_dcache_mmap_lock(struct address_space *) +{ +} + +static inline void tlb_finish_mmu(struct mmu_gather *) +{ +} + +static inline void get_file(struct file *) +{ +} + +static inline int vma_dup_policy(struct vm_area_struct *, struct vm_area_struct *) +{ + return 0; +} + +static inline int anon_vma_clone(struct vm_area_struct *, struct vm_area_struct *) +{ + return 0; +} + +static inline void vma_start_write(struct vm_area_struct *) +{ +} + +static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, + unsigned long start, + unsigned long end, + long adjust_next) +{ + (void)vma; + (void)start; + (void)end; + (void)adjust_next; +} + +static inline void vma_iter_free(struct vma_iterator *vmi) +{ + mas_destroy(&vmi->mas); +} + +static inline void vm_acct_memory(long pages) +{ +} + +static inline void vma_interval_tree_insert(struct vm_area_struct *, + struct rb_root_cached *) +{ +} + +static inline void vma_interval_tree_remove(struct vm_area_struct *, + struct rb_root_cached *) +{ +} + +static inline void flush_dcache_mmap_unlock(struct address_space *) +{ +} + +static inline void anon_vma_interval_tree_insert(struct anon_vma_chain*, + struct rb_root_cached *) +{ +} + +static inline void anon_vma_interval_tree_remove(struct anon_vma_chain*, + struct rb_root_cached *) +{ +} + +static inline void uprobe_mmap(struct vm_area_struct *) +{ +} + +static inline void uprobe_munmap(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + (void)vma; + (void)start; + (void)end; +} + +static inline void i_mmap_lock_write(struct address_space *) +{ +} + +static inline void anon_vma_lock_write(struct anon_vma *) +{ +} + +static inline void vma_assert_write_locked(struct vm_area_struct *) +{ +} + +static inline void unlink_anon_vmas(struct vm_area_struct *) +{ +} + +static inline void anon_vma_unlock_write(struct anon_vma *) +{ +} + +static inline void i_mmap_unlock_write(struct address_space *) +{ +} + +static inline void anon_vma_merge(struct vm_area_struct *, + struct vm_area_struct *) +{ +} + +static inline int userfaultfd_unmap_prep(struct vm_area_struct *vma, + unsigned long start, + unsigned long end, + struct list_head *unmaps) +{ + (void)vma; + (void)start; + (void)end; + (void)unmaps; + + return 0; +} + +static inline void mmap_write_downgrade(struct mm_struct *) +{ +} + +static inline void mmap_read_unlock(struct mm_struct *) +{ +} + +static inline void mmap_write_unlock(struct mm_struct *) +{ +} + +static inline bool can_modify_mm(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + (void)mm; + (void)start; + (void)end; + + return true; +} + +static inline void arch_unmap(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + (void)mm; + (void)start; + (void)end; +} + +static inline void mmap_assert_locked(struct mm_struct *) +{ +} + +static inline bool mpol_equal(struct mempolicy *, struct mempolicy *) +{ + return true; +} + +static inline void khugepaged_enter_vma(struct vm_area_struct *vma, + unsigned long vm_flags) +{ + (void)vma; + (void)vm_flags; +} + +static inline bool mapping_can_writeback(struct address_space *) +{ + return true; +} + +static inline bool is_vm_hugetlb_page(struct vm_area_struct *) +{ + return false; +} + +static inline bool vma_soft_dirty_enabled(struct vm_area_struct *) +{ + return false; +} + +static inline bool userfaultfd_wp(struct vm_area_struct *) +{ + return false; +} + +static inline void mmap_assert_write_locked(struct mm_struct *) +{ +} + +static inline void mutex_lock(struct mutex *) +{ +} + +static inline void mutex_unlock(struct mutex *) +{ +} + +static inline bool mutex_is_locked(struct mutex *) +{ + return true; +} + +static inline bool signal_pending(void *) +{ + return false; +} + +#endif /* __MM_VMA_INTERNAL_H */ -- 2.45.2