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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-12 20:39:53 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-12 20:39:53 +0300
commita667cb7a94d48a483fb5d6006fe04a440f1a42ce (patch)
treeccb9e596db96d53fcc4ba13a3370ec84912d0f22 /lib
parentcb1d150d809e2409725ba275c5101c4fc4465b8e (diff)
parent586187d7de71b4da7956ba588ae42253b9ff6482 (diff)
downloadlinux-a667cb7a94d48a483fb5d6006fe04a440f1a42ce.tar.xz
Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton: - a few misc things - the rest of MM - remove flex_arrays, replace with new simple radix-tree implementation * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (38 commits) Drop flex_arrays sctp: convert to genradix proc: commit to genradix generic radix trees selinux: convert to kvmalloc md: convert to kvmalloc openvswitch: convert to kvmalloc of: fix kmemleak crash caused by imbalance in early memory reservation mm: memblock: update comments and kernel-doc memblock: split checks whether a region should be skipped to a helper function memblock: remove memblock_{set,clear}_region_flags memblock: drop memblock_alloc_*_nopanic() variants memblock: memblock_alloc_try_nid: don't panic treewide: add checks for the return value of memblock_alloc*() swiotlb: add checks for the return value of memblock_alloc*() init/main: add checks for the return value of memblock_alloc*() mm/percpu: add checks for the return value of memblock_alloc*() sparc: add checks for the return value of memblock_alloc*() ia64: add checks for the return value of memblock_alloc*() arch: don't memset(0) memory returned by memblock_alloc() ...
Diffstat (limited to 'lib')
-rw-r--r--lib/Makefile5
-rw-r--r--lib/cpumask.c3
-rw-r--r--lib/flex_array.c398
-rw-r--r--lib/generic-radix-tree.c217
4 files changed, 223 insertions, 400 deletions
diff --git a/lib/Makefile b/lib/Makefile
index 647517940b29..4e066120a0d6 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -35,10 +35,11 @@ obj-y += lockref.o
obj-y += bcd.o div64.o sort.o parser.o debug_locks.o random32.o \
bust_spinlocks.o kasprintf.o bitmap.o scatterlist.o \
- gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \
+ gcd.o lcm.o list_sort.o uuid.o iov_iter.o clz_ctz.o \
bsearch.o find_bit.o llist.o memweight.o kfifo.o \
percpu-refcount.o rhashtable.o reciprocal_div.o \
- once.o refcount.o usercopy.o errseq.o bucket_locks.o
+ once.o refcount.o usercopy.o errseq.o bucket_locks.o \
+ generic-radix-tree.o
obj-$(CONFIG_STRING_SELFTEST) += test_string.o
obj-y += string_helpers.o
obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o
diff --git a/lib/cpumask.c b/lib/cpumask.c
index 087a3e9a0202..0cb672eb107c 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -165,6 +165,9 @@ EXPORT_SYMBOL(zalloc_cpumask_var);
void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask)
{
*mask = memblock_alloc(cpumask_size(), SMP_CACHE_BYTES);
+ if (!*mask)
+ panic("%s: Failed to allocate %u bytes\n", __func__,
+ cpumask_size());
}
/**
diff --git a/lib/flex_array.c b/lib/flex_array.c
deleted file mode 100644
index 2eed22fa507c..000000000000
--- a/lib/flex_array.c
+++ /dev/null
@@ -1,398 +0,0 @@
-/*
- * Flexible array managed in PAGE_SIZE parts
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright IBM Corporation, 2009
- *
- * Author: Dave Hansen <dave@linux.vnet.ibm.com>
- */
-
-#include <linux/flex_array.h>
-#include <linux/slab.h>
-#include <linux/stddef.h>
-#include <linux/export.h>
-#include <linux/reciprocal_div.h>
-
-struct flex_array_part {
- char elements[FLEX_ARRAY_PART_SIZE];
-};
-
-/*
- * If a user requests an allocation which is small
- * enough, we may simply use the space in the
- * flex_array->parts[] array to store the user
- * data.
- */
-static inline int elements_fit_in_base(struct flex_array *fa)
-{
- int data_size = fa->element_size * fa->total_nr_elements;
- if (data_size <= FLEX_ARRAY_BASE_BYTES_LEFT)
- return 1;
- return 0;
-}
-
-/**
- * flex_array_alloc - allocate a new flexible array
- * @element_size: the size of individual elements in the array
- * @total: total number of elements that this should hold
- * @flags: page allocation flags to use for base array
- *
- * Note: all locking must be provided by the caller.
- *
- * @total is used to size internal structures. If the user ever
- * accesses any array indexes >=@total, it will produce errors.
- *
- * The maximum number of elements is defined as: the number of
- * elements that can be stored in a page times the number of
- * page pointers that we can fit in the base structure or (using
- * integer math):
- *
- * (PAGE_SIZE/element_size) * (PAGE_SIZE-8)/sizeof(void *)
- *
- * Here's a table showing example capacities. Note that the maximum
- * index that the get/put() functions is just nr_objects-1. This
- * basically means that you get 4MB of storage on 32-bit and 2MB on
- * 64-bit.
- *
- *
- * Element size | Objects | Objects |
- * PAGE_SIZE=4k | 32-bit | 64-bit |
- * ---------------------------------|
- * 1 bytes | 4177920 | 2088960 |
- * 2 bytes | 2088960 | 1044480 |
- * 3 bytes | 1392300 | 696150 |
- * 4 bytes | 1044480 | 522240 |
- * 32 bytes | 130560 | 65408 |
- * 33 bytes | 126480 | 63240 |
- * 2048 bytes | 2040 | 1020 |
- * 2049 bytes | 1020 | 510 |
- * void * | 1044480 | 261120 |
- *
- * Since 64-bit pointers are twice the size, we lose half the
- * capacity in the base structure. Also note that no effort is made
- * to efficiently pack objects across page boundaries.
- */
-struct flex_array *flex_array_alloc(int element_size, unsigned int total,
- gfp_t flags)
-{
- struct flex_array *ret;
- int elems_per_part = 0;
- int max_size = 0;
- struct reciprocal_value reciprocal_elems = { 0 };
-
- if (element_size) {
- elems_per_part = FLEX_ARRAY_ELEMENTS_PER_PART(element_size);
- reciprocal_elems = reciprocal_value(elems_per_part);
- max_size = FLEX_ARRAY_NR_BASE_PTRS * elems_per_part;
- }
-
- /* max_size will end up 0 if element_size > PAGE_SIZE */
- if (total > max_size)
- return NULL;
- ret = kzalloc(sizeof(struct flex_array), flags);
- if (!ret)
- return NULL;
- ret->element_size = element_size;
- ret->total_nr_elements = total;
- ret->elems_per_part = elems_per_part;
- ret->reciprocal_elems = reciprocal_elems;
- if (elements_fit_in_base(ret) && !(flags & __GFP_ZERO))
- memset(&ret->parts[0], FLEX_ARRAY_FREE,
- FLEX_ARRAY_BASE_BYTES_LEFT);
- return ret;
-}
-EXPORT_SYMBOL(flex_array_alloc);
-
-static int fa_element_to_part_nr(struct flex_array *fa,
- unsigned int element_nr)
-{
- /*
- * if element_size == 0 we don't get here, so we never touch
- * the zeroed fa->reciprocal_elems, which would yield invalid
- * results
- */
- return reciprocal_divide(element_nr, fa->reciprocal_elems);
-}
-
-/**
- * flex_array_free_parts - just free the second-level pages
- * @fa: the flex array from which to free parts
- *
- * This is to be used in cases where the base 'struct flex_array'
- * has been statically allocated and should not be free.
- */
-void flex_array_free_parts(struct flex_array *fa)
-{
- int part_nr;
-
- if (elements_fit_in_base(fa))
- return;
- for (part_nr = 0; part_nr < FLEX_ARRAY_NR_BASE_PTRS; part_nr++)
- kfree(fa->parts[part_nr]);
-}
-EXPORT_SYMBOL(flex_array_free_parts);
-
-void flex_array_free(struct flex_array *fa)
-{
- flex_array_free_parts(fa);
- kfree(fa);
-}
-EXPORT_SYMBOL(flex_array_free);
-
-static unsigned int index_inside_part(struct flex_array *fa,
- unsigned int element_nr,
- unsigned int part_nr)
-{
- unsigned int part_offset;
-
- part_offset = element_nr - part_nr * fa->elems_per_part;
- return part_offset * fa->element_size;
-}
-
-static struct flex_array_part *
-__fa_get_part(struct flex_array *fa, int part_nr, gfp_t flags)
-{
- struct flex_array_part *part = fa->parts[part_nr];
- if (!part) {
- part = kmalloc(sizeof(struct flex_array_part), flags);
- if (!part)
- return NULL;
- if (!(flags & __GFP_ZERO))
- memset(part, FLEX_ARRAY_FREE,
- sizeof(struct flex_array_part));
- fa->parts[part_nr] = part;
- }
- return part;
-}
-
-/**
- * flex_array_put - copy data into the array at @element_nr
- * @fa: the flex array to copy data into
- * @element_nr: index of the position in which to insert
- * the new element.
- * @src: address of data to copy into the array
- * @flags: page allocation flags to use for array expansion
- *
- *
- * Note that this *copies* the contents of @src into
- * the array. If you are trying to store an array of
- * pointers, make sure to pass in &ptr instead of ptr.
- * You may instead wish to use the flex_array_put_ptr()
- * helper function.
- *
- * Locking must be provided by the caller.
- */
-int flex_array_put(struct flex_array *fa, unsigned int element_nr, void *src,
- gfp_t flags)
-{
- int part_nr = 0;
- struct flex_array_part *part;
- void *dst;
-
- if (element_nr >= fa->total_nr_elements)
- return -ENOSPC;
- if (!fa->element_size)
- return 0;
- if (elements_fit_in_base(fa))
- part = (struct flex_array_part *)&fa->parts[0];
- else {
- part_nr = fa_element_to_part_nr(fa, element_nr);
- part = __fa_get_part(fa, part_nr, flags);
- if (!part)
- return -ENOMEM;
- }
- dst = &part->elements[index_inside_part(fa, element_nr, part_nr)];
- memcpy(dst, src, fa->element_size);
- return 0;
-}
-EXPORT_SYMBOL(flex_array_put);
-
-/**
- * flex_array_clear - clear element in array at @element_nr
- * @fa: the flex array of the element.
- * @element_nr: index of the position to clear.
- *
- * Locking must be provided by the caller.
- */
-int flex_array_clear(struct flex_array *fa, unsigned int element_nr)
-{
- int part_nr = 0;
- struct flex_array_part *part;
- void *dst;
-
- if (element_nr >= fa->total_nr_elements)
- return -ENOSPC;
- if (!fa->element_size)
- return 0;
- if (elements_fit_in_base(fa))
- part = (struct flex_array_part *)&fa->parts[0];
- else {
- part_nr = fa_element_to_part_nr(fa, element_nr);
- part = fa->parts[part_nr];
- if (!part)
- return -EINVAL;
- }
- dst = &part->elements[index_inside_part(fa, element_nr, part_nr)];
- memset(dst, FLEX_ARRAY_FREE, fa->element_size);
- return 0;
-}
-EXPORT_SYMBOL(flex_array_clear);
-
-/**
- * flex_array_prealloc - guarantee that array space exists
- * @fa: the flex array for which to preallocate parts
- * @start: index of first array element for which space is allocated
- * @nr_elements: number of elements for which space is allocated
- * @flags: page allocation flags
- *
- * This will guarantee that no future calls to flex_array_put()
- * will allocate memory. It can be used if you are expecting to
- * be holding a lock or in some atomic context while writing
- * data into the array.
- *
- * Locking must be provided by the caller.
- */
-int flex_array_prealloc(struct flex_array *fa, unsigned int start,
- unsigned int nr_elements, gfp_t flags)
-{
- int start_part;
- int end_part;
- int part_nr;
- unsigned int end;
- struct flex_array_part *part;
-
- if (!start && !nr_elements)
- return 0;
- if (start >= fa->total_nr_elements)
- return -ENOSPC;
- if (!nr_elements)
- return 0;
-
- end = start + nr_elements - 1;
-
- if (end >= fa->total_nr_elements)
- return -ENOSPC;
- if (!fa->element_size)
- return 0;
- if (elements_fit_in_base(fa))
- return 0;
- start_part = fa_element_to_part_nr(fa, start);
- end_part = fa_element_to_part_nr(fa, end);
- for (part_nr = start_part; part_nr <= end_part; part_nr++) {
- part = __fa_get_part(fa, part_nr, flags);
- if (!part)
- return -ENOMEM;
- }
- return 0;
-}
-EXPORT_SYMBOL(flex_array_prealloc);
-
-/**
- * flex_array_get - pull data back out of the array
- * @fa: the flex array from which to extract data
- * @element_nr: index of the element to fetch from the array
- *
- * Returns a pointer to the data at index @element_nr. Note
- * that this is a copy of the data that was passed in. If you
- * are using this to store pointers, you'll get back &ptr. You
- * may instead wish to use the flex_array_get_ptr helper.
- *
- * Locking must be provided by the caller.
- */
-void *flex_array_get(struct flex_array *fa, unsigned int element_nr)
-{
- int part_nr = 0;
- struct flex_array_part *part;
-
- if (!fa->element_size)
- return NULL;
- if (element_nr >= fa->total_nr_elements)
- return NULL;
- if (elements_fit_in_base(fa))
- part = (struct flex_array_part *)&fa->parts[0];
- else {
- part_nr = fa_element_to_part_nr(fa, element_nr);
- part = fa->parts[part_nr];
- if (!part)
- return NULL;
- }
- return &part->elements[index_inside_part(fa, element_nr, part_nr)];
-}
-EXPORT_SYMBOL(flex_array_get);
-
-/**
- * flex_array_get_ptr - pull a ptr back out of the array
- * @fa: the flex array from which to extract data
- * @element_nr: index of the element to fetch from the array
- *
- * Returns the pointer placed in the flex array at element_nr using
- * flex_array_put_ptr(). This function should not be called if the
- * element in question was not set using the _put_ptr() helper.
- */
-void *flex_array_get_ptr(struct flex_array *fa, unsigned int element_nr)
-{
- void **tmp;
-
- tmp = flex_array_get(fa, element_nr);
- if (!tmp)
- return NULL;
-
- return *tmp;
-}
-EXPORT_SYMBOL(flex_array_get_ptr);
-
-static int part_is_free(struct flex_array_part *part)
-{
- int i;
-
- for (i = 0; i < sizeof(struct flex_array_part); i++)
- if (part->elements[i] != FLEX_ARRAY_FREE)
- return 0;
- return 1;
-}
-
-/**
- * flex_array_shrink - free unused second-level pages
- * @fa: the flex array to shrink
- *
- * Frees all second-level pages that consist solely of unused
- * elements. Returns the number of pages freed.
- *
- * Locking must be provided by the caller.
- */
-int flex_array_shrink(struct flex_array *fa)
-{
- struct flex_array_part *part;
- int part_nr;
- int ret = 0;
-
- if (!fa->total_nr_elements || !fa->element_size)
- return 0;
- if (elements_fit_in_base(fa))
- return ret;
- for (part_nr = 0; part_nr < FLEX_ARRAY_NR_BASE_PTRS; part_nr++) {
- part = fa->parts[part_nr];
- if (!part)
- continue;
- if (part_is_free(part)) {
- fa->parts[part_nr] = NULL;
- kfree(part);
- ret++;
- }
- }
- return ret;
-}
-EXPORT_SYMBOL(flex_array_shrink);
diff --git a/lib/generic-radix-tree.c b/lib/generic-radix-tree.c
new file mode 100644
index 000000000000..a7bafc413730
--- /dev/null
+++ b/lib/generic-radix-tree.c
@@ -0,0 +1,217 @@
+
+#include <linux/export.h>
+#include <linux/generic-radix-tree.h>
+#include <linux/gfp.h>
+
+#define GENRADIX_ARY (PAGE_SIZE / sizeof(struct genradix_node *))
+#define GENRADIX_ARY_SHIFT ilog2(GENRADIX_ARY)
+
+struct genradix_node {
+ union {
+ /* Interior node: */
+ struct genradix_node *children[GENRADIX_ARY];
+
+ /* Leaf: */
+ u8 data[PAGE_SIZE];
+ };
+};
+
+static inline int genradix_depth_shift(unsigned depth)
+{
+ return PAGE_SHIFT + GENRADIX_ARY_SHIFT * depth;
+}
+
+/*
+ * Returns size (of data, in bytes) that a tree of a given depth holds:
+ */
+static inline size_t genradix_depth_size(unsigned depth)
+{
+ return 1UL << genradix_depth_shift(depth);
+}
+
+/* depth that's needed for a genradix that can address up to ULONG_MAX: */
+#define GENRADIX_MAX_DEPTH \
+ DIV_ROUND_UP(BITS_PER_LONG - PAGE_SHIFT, GENRADIX_ARY_SHIFT)
+
+#define GENRADIX_DEPTH_MASK \
+ ((unsigned long) (roundup_pow_of_two(GENRADIX_MAX_DEPTH + 1) - 1))
+
+unsigned genradix_root_to_depth(struct genradix_root *r)
+{
+ return (unsigned long) r & GENRADIX_DEPTH_MASK;
+}
+
+struct genradix_node *genradix_root_to_node(struct genradix_root *r)
+{
+ return (void *) ((unsigned long) r & ~GENRADIX_DEPTH_MASK);
+}
+
+/*
+ * Returns pointer to the specified byte @offset within @radix, or NULL if not
+ * allocated
+ */
+void *__genradix_ptr(struct __genradix *radix, size_t offset)
+{
+ struct genradix_root *r = READ_ONCE(radix->root);
+ struct genradix_node *n = genradix_root_to_node(r);
+ unsigned level = genradix_root_to_depth(r);
+
+ if (ilog2(offset) >= genradix_depth_shift(level))
+ return NULL;
+
+ while (1) {
+ if (!n)
+ return NULL;
+ if (!level)
+ break;
+
+ level--;
+
+ n = n->children[offset >> genradix_depth_shift(level)];
+ offset &= genradix_depth_size(level) - 1;
+ }
+
+ return &n->data[offset];
+}
+EXPORT_SYMBOL(__genradix_ptr);
+
+/*
+ * Returns pointer to the specified byte @offset within @radix, allocating it if
+ * necessary - newly allocated slots are always zeroed out:
+ */
+void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
+ gfp_t gfp_mask)
+{
+ struct genradix_root *v = READ_ONCE(radix->root);
+ struct genradix_node *n, *new_node = NULL;
+ unsigned level;
+
+ /* Increase tree depth if necessary: */
+ while (1) {
+ struct genradix_root *r = v, *new_root;
+
+ n = genradix_root_to_node(r);
+ level = genradix_root_to_depth(r);
+
+ if (n && ilog2(offset) < genradix_depth_shift(level))
+ break;
+
+ if (!new_node) {
+ new_node = (void *)
+ __get_free_page(gfp_mask|__GFP_ZERO);
+ if (!new_node)
+ return NULL;
+ }
+
+ new_node->children[0] = n;
+ new_root = ((struct genradix_root *)
+ ((unsigned long) new_node | (n ? level + 1 : 0)));
+
+ if ((v = cmpxchg_release(&radix->root, r, new_root)) == r) {
+ v = new_root;
+ new_node = NULL;
+ }
+ }
+
+ while (level--) {
+ struct genradix_node **p =
+ &n->children[offset >> genradix_depth_shift(level)];
+ offset &= genradix_depth_size(level) - 1;
+
+ n = READ_ONCE(*p);
+ if (!n) {
+ if (!new_node) {
+ new_node = (void *)
+ __get_free_page(gfp_mask|__GFP_ZERO);
+ if (!new_node)
+ return NULL;
+ }
+
+ if (!(n = cmpxchg_release(p, NULL, new_node)))
+ swap(n, new_node);
+ }
+ }
+
+ if (new_node)
+ free_page((unsigned long) new_node);
+
+ return &n->data[offset];
+}
+EXPORT_SYMBOL(__genradix_ptr_alloc);
+
+void *__genradix_iter_peek(struct genradix_iter *iter,
+ struct __genradix *radix,
+ size_t objs_per_page)
+{
+ struct genradix_root *r;
+ struct genradix_node *n;
+ unsigned level, i;
+restart:
+ r = READ_ONCE(radix->root);
+ if (!r)
+ return NULL;
+
+ n = genradix_root_to_node(r);
+ level = genradix_root_to_depth(r);
+
+ if (ilog2(iter->offset) >= genradix_depth_shift(level))
+ return NULL;
+
+ while (level) {
+ level--;
+
+ i = (iter->offset >> genradix_depth_shift(level)) &
+ (GENRADIX_ARY - 1);
+
+ while (!n->children[i]) {
+ i++;
+ iter->offset = round_down(iter->offset +
+ genradix_depth_size(level),
+ genradix_depth_size(level));
+ iter->pos = (iter->offset >> PAGE_SHIFT) *
+ objs_per_page;
+ if (i == GENRADIX_ARY)
+ goto restart;
+ }
+
+ n = n->children[i];
+ }
+
+ return &n->data[iter->offset & (PAGE_SIZE - 1)];
+}
+EXPORT_SYMBOL(__genradix_iter_peek);
+
+static void genradix_free_recurse(struct genradix_node *n, unsigned level)
+{
+ if (level) {
+ unsigned i;
+
+ for (i = 0; i < GENRADIX_ARY; i++)
+ if (n->children[i])
+ genradix_free_recurse(n->children[i], level - 1);
+ }
+
+ free_page((unsigned long) n);
+}
+
+int __genradix_prealloc(struct __genradix *radix, size_t size,
+ gfp_t gfp_mask)
+{
+ size_t offset;
+
+ for (offset = 0; offset < size; offset += PAGE_SIZE)
+ if (!__genradix_ptr_alloc(radix, offset, gfp_mask))
+ return -ENOMEM;
+
+ return 0;
+}
+EXPORT_SYMBOL(__genradix_prealloc);
+
+void __genradix_free(struct __genradix *radix)
+{
+ struct genradix_root *r = xchg(&radix->root, NULL);
+
+ genradix_free_recurse(genradix_root_to_node(r),
+ genradix_root_to_depth(r));
+}
+EXPORT_SYMBOL(__genradix_free);