VisionFive2 Linux kernel

StarFive Tech Linux Kernel for VisionFive (JH7110) boards (mirror)

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ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   1) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   2) #include <linux/export.h>
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   3) #include <linux/generic-radix-tree.h>
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   4) #include <linux/gfp.h>
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700   5) #include <linux/kmemleak.h>
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   6) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   7) #define GENRADIX_ARY		(PAGE_SIZE / sizeof(struct genradix_node *))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   8) #define GENRADIX_ARY_SHIFT	ilog2(GENRADIX_ARY)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700   9) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  10) struct genradix_node {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  11) 	union {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  12) 		/* Interior node: */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  13) 		struct genradix_node	*children[GENRADIX_ARY];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  14) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  15) 		/* Leaf: */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  16) 		u8			data[PAGE_SIZE];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  17) 	};
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  18) };
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  19) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  20) static inline int genradix_depth_shift(unsigned depth)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  21) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  22) 	return PAGE_SHIFT + GENRADIX_ARY_SHIFT * depth;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  23) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  24) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  25) /*
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  26)  * Returns size (of data, in bytes) that a tree of a given depth holds:
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  27)  */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  28) static inline size_t genradix_depth_size(unsigned depth)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  29) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  30) 	return 1UL << genradix_depth_shift(depth);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  31) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  32) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  33) /* depth that's needed for a genradix that can address up to ULONG_MAX: */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  34) #define GENRADIX_MAX_DEPTH	\
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  35) 	DIV_ROUND_UP(BITS_PER_LONG - PAGE_SHIFT, GENRADIX_ARY_SHIFT)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  36) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  37) #define GENRADIX_DEPTH_MASK				\
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  38) 	((unsigned long) (roundup_pow_of_two(GENRADIX_MAX_DEPTH + 1) - 1))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  39) 
e3f4faa42095c (Valdis Kletnieks 2019-09-25 16:46:23 -0700  40) static inline unsigned genradix_root_to_depth(struct genradix_root *r)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  41) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  42) 	return (unsigned long) r & GENRADIX_DEPTH_MASK;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  43) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  44) 
e3f4faa42095c (Valdis Kletnieks 2019-09-25 16:46:23 -0700  45) static inline struct genradix_node *genradix_root_to_node(struct genradix_root *r)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  46) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  47) 	return (void *) ((unsigned long) r & ~GENRADIX_DEPTH_MASK);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  48) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  49) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  50) /*
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  51)  * Returns pointer to the specified byte @offset within @radix, or NULL if not
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  52)  * allocated
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  53)  */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  54) void *__genradix_ptr(struct __genradix *radix, size_t offset)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  55) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  56) 	struct genradix_root *r = READ_ONCE(radix->root);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  57) 	struct genradix_node *n = genradix_root_to_node(r);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  58) 	unsigned level		= genradix_root_to_depth(r);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  59) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  60) 	if (ilog2(offset) >= genradix_depth_shift(level))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  61) 		return NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  62) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  63) 	while (1) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  64) 		if (!n)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  65) 			return NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  66) 		if (!level)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  67) 			break;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  68) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  69) 		level--;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  70) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  71) 		n = n->children[offset >> genradix_depth_shift(level)];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  72) 		offset &= genradix_depth_size(level) - 1;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  73) 	}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  74) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  75) 	return &n->data[offset];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  76) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  77) EXPORT_SYMBOL(__genradix_ptr);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700  78) 
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  79) static inline struct genradix_node *genradix_alloc_node(gfp_t gfp_mask)
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  80) {
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  81) 	struct genradix_node *node;
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  82) 
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  83) 	node = (struct genradix_node *)__get_free_page(gfp_mask|__GFP_ZERO);
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  84) 
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  85) 	/*
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  86) 	 * We're using pages (not slab allocations) directly for kernel data
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  87) 	 * structures, so we need to explicitly inform kmemleak of them in order
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  88) 	 * to avoid false positive memory leak reports.
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  89) 	 */
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  90) 	kmemleak_alloc(node, PAGE_SIZE, 1, gfp_mask);
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  91) 	return node;
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  92) }
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  93) 
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  94) static inline void genradix_free_node(struct genradix_node *node)
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  95) {
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  96) 	kmemleak_free(node);
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  97) 	free_page((unsigned long)node);
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  98) }
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700  99) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 100) /*
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 101)  * Returns pointer to the specified byte @offset within @radix, allocating it if
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 102)  * necessary - newly allocated slots are always zeroed out:
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 103)  */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 104) void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 105) 			   gfp_t gfp_mask)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 106) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 107) 	struct genradix_root *v = READ_ONCE(radix->root);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 108) 	struct genradix_node *n, *new_node = NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 109) 	unsigned level;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 110) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 111) 	/* Increase tree depth if necessary: */
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 112) 	while (1) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 113) 		struct genradix_root *r = v, *new_root;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 114) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 115) 		n	= genradix_root_to_node(r);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 116) 		level	= genradix_root_to_depth(r);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 117) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 118) 		if (n && ilog2(offset) < genradix_depth_shift(level))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 119) 			break;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 120) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 121) 		if (!new_node) {
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700 122) 			new_node = genradix_alloc_node(gfp_mask);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 123) 			if (!new_node)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 124) 				return NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 125) 		}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 126) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 127) 		new_node->children[0] = n;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 128) 		new_root = ((struct genradix_root *)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 129) 			    ((unsigned long) new_node | (n ? level + 1 : 0)));
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 130) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 131) 		if ((v = cmpxchg_release(&radix->root, r, new_root)) == r) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 132) 			v = new_root;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 133) 			new_node = NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 134) 		}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 135) 	}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 136) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 137) 	while (level--) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 138) 		struct genradix_node **p =
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 139) 			&n->children[offset >> genradix_depth_shift(level)];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 140) 		offset &= genradix_depth_size(level) - 1;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 141) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 142) 		n = READ_ONCE(*p);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 143) 		if (!n) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 144) 			if (!new_node) {
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700 145) 				new_node = genradix_alloc_node(gfp_mask);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 146) 				if (!new_node)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 147) 					return NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 148) 			}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 149) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 150) 			if (!(n = cmpxchg_release(p, NULL, new_node)))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 151) 				swap(n, new_node);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 152) 		}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 153) 	}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 154) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 155) 	if (new_node)
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700 156) 		genradix_free_node(new_node);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 157) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 158) 	return &n->data[offset];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 159) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 160) EXPORT_SYMBOL(__genradix_ptr_alloc);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 161) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 162) void *__genradix_iter_peek(struct genradix_iter *iter,
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 163) 			   struct __genradix *radix,
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 164) 			   size_t objs_per_page)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 165) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 166) 	struct genradix_root *r;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 167) 	struct genradix_node *n;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 168) 	unsigned level, i;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 169) restart:
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 170) 	r = READ_ONCE(radix->root);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 171) 	if (!r)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 172) 		return NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 173) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 174) 	n	= genradix_root_to_node(r);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 175) 	level	= genradix_root_to_depth(r);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 176) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 177) 	if (ilog2(iter->offset) >= genradix_depth_shift(level))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 178) 		return NULL;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 179) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 180) 	while (level) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 181) 		level--;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 182) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 183) 		i = (iter->offset >> genradix_depth_shift(level)) &
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 184) 			(GENRADIX_ARY - 1);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 185) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 186) 		while (!n->children[i]) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 187) 			i++;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 188) 			iter->offset = round_down(iter->offset +
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 189) 					   genradix_depth_size(level),
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 190) 					   genradix_depth_size(level));
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 191) 			iter->pos = (iter->offset >> PAGE_SHIFT) *
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 192) 				objs_per_page;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 193) 			if (i == GENRADIX_ARY)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 194) 				goto restart;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 195) 		}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 196) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 197) 		n = n->children[i];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 198) 	}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 199) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 200) 	return &n->data[iter->offset & (PAGE_SIZE - 1)];
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 201) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 202) EXPORT_SYMBOL(__genradix_iter_peek);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 203) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 204) static void genradix_free_recurse(struct genradix_node *n, unsigned level)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 205) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 206) 	if (level) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 207) 		unsigned i;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 208) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 209) 		for (i = 0; i < GENRADIX_ARY; i++)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 210) 			if (n->children[i])
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 211) 				genradix_free_recurse(n->children[i], level - 1);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 212) 	}
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 213) 
3c52b0af059e1 (Eric Biggers     2019-10-14 14:11:54 -0700 214) 	genradix_free_node(n);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 215) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 216) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 217) int __genradix_prealloc(struct __genradix *radix, size_t size,
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 218) 			gfp_t gfp_mask)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 219) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 220) 	size_t offset;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 221) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 222) 	for (offset = 0; offset < size; offset += PAGE_SIZE)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 223) 		if (!__genradix_ptr_alloc(radix, offset, gfp_mask))
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 224) 			return -ENOMEM;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 225) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 226) 	return 0;
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 227) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 228) EXPORT_SYMBOL(__genradix_prealloc);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 229) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 230) void __genradix_free(struct __genradix *radix)
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 231) {
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 232) 	struct genradix_root *r = xchg(&radix->root, NULL);
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 233) 
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 234) 	genradix_free_recurse(genradix_root_to_node(r),
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 235) 			      genradix_root_to_depth(r));
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 236) }
ba20ba2e3743b (Kent Overstreet  2019-03-11 23:31:14 -0700 237) EXPORT_SYMBOL(__genradix_free);