Improved header dependency tree

1 files changed, 458 insertions, 0 deletions

diff --git a/common/mem_regions.c b/common/mem_regions.c
new file mode 100644
index 0000000..ebcff50
--- /dev/null
+++ b/common/mem_regions.c
@@ -0,0 +1,458 @@
+#include <apos/mem_regions.h>
+#include <apos/mem_nodes.h>
+#include <apos/pmem.h>
+#include <apos/mem.h>
+
+#define mark_region_used(r) ((r) = 1)
+#define mark_region_unused(r) ((r) = 0)
+#define is_region_used(r) (r)
+
+static size_t __uvmem_size = 0;
+
+/* pretty major slowdown when we get to some really massive numbers, not
+ * entirely sure why. Will need to check up on this at some point, have I
+ * somehow managed to come up with a _very_ bad situation for my sp_trees?
+ *
+ * EDIT: apparently, yeah. Max depth of 106 with a million entries, interesting.
+ * I guess since in this scenario all sizes are 1, and I just shove everything
+ * to the right? Maybe?
+ *
+ * EDIT upon EDIT: yeah, when taking the start position of the region into
+ * account we get a much more sensible max depth of 39 for 5 million entries.
+ * Seems I have found a weakness in sp_trees :D
+ *
+ * Duplicate entries don't work well with any trees, I think. Good to know,
+ * maybe not even anything with sp_trees but more a weakness of binary trees in
+ * general?
+ */
+static struct sp_mem *sp_free_insert_region(struct sp_reg_root *r, struct sp_mem *m)
+{
+	struct sp_node *n = sp_root(r->free_regions), *p = NULL;
+	size_t start = m->start;
+	size_t size = m->end - m->start;
+	enum sp_dir d = LEFT;
+
+	m->sp_n = (struct sp_node){0};
+
+	while(n){
+		struct sp_mem *t = mem_container(n);
+		size_t nsize = t->end - t->start;
+		p = n;
+
+		if(size < nsize){
+			n = sp_left(n);
+			d = LEFT;
+		}
+
+		else if(size > nsize) {
+			n = sp_right(n);
+			d = RIGHT;
+		}
+
+		else if (start < t->start){
+			n = sp_left(n);
+			d = LEFT;
+		}
+
+		else {
+			n = sp_right(n);
+			d = RIGHT;
+		}
+	}
+
+	if(sp_root(r->free_regions))
+		sp_insert(&sp_root(r->free_regions), p, &m->sp_n, d);
+	else
+		sp_root(r->free_regions) = &m->sp_n;
+
+	return m;
+}
+
+static struct sp_mem *sp_used_insert_region(struct sp_reg_root *r, struct sp_mem *m)
+{
+	struct sp_node *n = sp_root(r->used_regions), *p = NULL;
+	vm_t start = m->start;
+	enum sp_dir d = LEFT;
+
+	m->sp_n = (struct sp_node){0};
+
+	while(n){
+		struct sp_mem *t = mem_container(n);
+
+		p = n;
+
+		if(start < t->start){
+			n = sp_left(n);
+			d = LEFT;
+		}
+
+		else {
+			/* we should never encounter a situation where start =
+			 * t->start */
+			n = sp_right(n);
+			d = RIGHT;
+		}
+	}
+
+	if(sp_root(r->used_regions))
+		sp_insert(&sp_root(r->used_regions), p, &m->sp_n, d);
+	else
+		sp_root(r->used_regions) = &m->sp_n;
+
+	return m;
+}
+
+stat_t sp_mem_init(struct sp_reg_root *r, vm_t start, size_t arena_size)
+{
+	/* convert bytes to pages */
+	start = __page(start);
+	arena_size = __page(arena_size);
+	struct sp_mem *m = get_mem_node();
+	m->start = start;
+	m->end = start + arena_size;
+	sp_free_insert_region(r, m);
+
+	return OK;
+}
+
+static void __sp_mem_destroy(struct sp_node *n)
+{
+	if(!n)
+		return;
+
+	__sp_mem_destroy(sp_left(n));
+	__sp_mem_destroy(sp_right(n));
+
+	struct sp_mem *m = mem_container(n);
+	free_mem_node(m);
+}
+
+void sp_mem_destroy(struct sp_reg_root *r)
+{
+	__sp_mem_destroy(sp_root(r->free_regions));
+	__sp_mem_destroy(sp_root(r->used_regions));
+}
+
+/* interestingly this is now the main bottleneck :D
+ *
+ * eh, it's not a massive thing I guess, maybe the code could be a bit quicker
+ * but I mean 10 000 000 memory allocations in 20 s is good enough for now
+ * */
+struct sp_mem *sp_used_find(struct sp_reg_root *r, vm_t start)
+{
+	struct sp_node *n = sp_root(r->used_regions);
+	while(n){
+		struct sp_mem *t = mem_container(n);
+		if(start == t->start)
+			return t;
+
+		if(start < t->start)
+			n = sp_left(n);
+		else
+			n = sp_right(n);
+	}
+
+	return 0;
+}
+
+static struct sp_mem *sp_mem_create_region(vm_t start, vm_t end,
+		struct sp_mem *prev, struct sp_mem *next)
+{
+	struct sp_mem *m = get_mem_node();
+	m->start = start;
+	m->end = end;
+	m->prev = prev;
+	m->next = next;
+	return m;
+}
+
+/* TODO: should probably check if this actually works :D seems to do, but that's
+ * just from really quick checking */
+static size_t po_align(size_t s)
+{
+	for(size_t o = __mm_max_order; o > 0; --o){
+		if(s >= __o_size(o))
+			return __o_size(o);
+	}
+
+	return 0;
+}
+
+struct sp_mem *sp_find_used_closest(struct sp_reg_root *r, vm_t start)
+{
+	struct sp_mem *closest = 0;
+	size_t md = (size_t)(-1);
+	struct sp_node *n = sp_root(r->used_regions);
+	if(!n)
+		return mem_container(sp_root(r->free_regions));
+
+	while(n){
+		struct sp_mem *t = mem_container(n);
+		size_t d = ABS((ssize_t)start - (ssize_t)t->start);
+
+		if(d == 0) /* exact match */
+			return t;
+
+		if(d < md){ /* closest so far */
+			closest = t;
+			md = d;
+		}
+
+		if(start < t->start)
+			n = sp_left(n);
+		else
+			n = sp_right(n);
+	}
+
+	return closest;
+}
+
+/* should probably document this a bit better but in short, look for the "best"
+ * free block, meaning one that is hopefully aligned so as to allow us to later
+ * map it to higher order pages. If no block is found such that that is
+ * possible, also keep track of the smallest block that we found that the region
+ * still fits in, unaligned. If none of these criteria are met, a NULL is
+ * returned. Note that this does not check *all* possible memory blocks, only
+ * going up in increasing size so as to save time. */
+struct sp_mem *sp_find_free(struct sp_reg_root *r, size_t size, size_t *align)
+{
+	*align = 0;
+	size_t offset = __page(po_align(__addr(size)));
+	struct sp_mem *quick_best = 0;
+	struct sp_node *n = sp_root(r->free_regions);
+	while(n){
+		struct sp_mem *t = mem_container(n);
+		vm_t start = align_up(t->start, offset);
+
+		size_t qsize = t->end - t->start;
+		size_t bsize = t->end - start;
+
+		if(!quick_best && size <= qsize)
+			quick_best = t;
+
+		if(size <= bsize){
+			*align = start - t->start;
+			return t;
+		}
+
+		n = sp_right(n);
+	}
+
+	return quick_best;
+}
+
+static size_t sp_use_region(struct sp_reg_root *r, struct sp_mem *m,
+		size_t pages, size_t align)
+{
+	sp_remove(&sp_root(r->free_regions), &m->sp_n);
+
+	vm_t pre_start = m->start;
+	vm_t pre_end = pre_start + align;
+	
+	vm_t start = pre_end;
+	vm_t end = start + pages;
+
+	vm_t post_start = end;
+	vm_t post_end = m->end;
+
+	if(pre_start != pre_end){
+		struct sp_mem *n = sp_mem_create_region(pre_start, pre_end, m->prev, m);
+		m->prev = n;
+		if(n->prev)
+			n->prev->next = n;
+
+		sp_free_insert_region(r, n);
+	}
+
+	if(post_start != post_end){
+		struct sp_mem *n = sp_mem_create_region(post_start, post_end, m, m->next);
+		m->next = n;
+		if(n->next)
+			n->next->prev = n;
+
+		sp_free_insert_region(r, n);
+	}
+
+	m->end = end;
+	m->start = start;
+	mark_region_used(m->flags);
+	sp_used_insert_region(r, m);
+	return __addr(start);
+}
+
+/* apparently Linux doesn't necessarily give a shit about mmap hints, so I'll
+ * just ignore them for now. Note that alloc_region should only be used when
+ * mmap is called with MAP_ANON, all other situations should be handled in some
+ * fs server */
+vm_t alloc_region(struct sp_reg_root *r,
+		size_t size, size_t *actual_size)
+{
+	*actual_size = align_up(size, BASE_PAGE_SIZE);
+	size_t pages = __page(*actual_size);
+
+	/* find best fitting, alignment etc. */
+	size_t align = 0;
+	struct sp_mem *m = sp_find_free(r, pages, &align);
+	if(!m)
+		return 0;
+
+	return sp_use_region(r, m, pages, align);
+}
+
+
+vm_t alloc_fixed_region(struct sp_reg_root *r,
+		vm_t start, size_t size, size_t *actual_size)
+{
+	size_t asize = align_up(size, BASE_PAGE_SIZE);
+	if(actual_size)
+		*actual_size = asize;
+
+	size_t pages = __page(asize);
+	start = __page(start);
+
+	struct sp_mem *m = sp_find_used_closest(r, start);
+	if(!m)
+		return 0;
+
+	/* locate actual region where start is between the region start and end */
+	while(!((m->start <= start) && (start <= m->end))){
+		if(start > m->start)
+			m = m->next;
+		else
+			m = m->prev;
+	}
+
+	/* if region is already in use, forget it */
+	if(is_region_used(m->flags))
+		return 0;
+
+	/* region is too small */
+	if(start + pages > m->end)
+		return 0;
+
+	/* actually start marking region used */
+	return sp_use_region(r, m, pages, start - m->start);
+}
+
+static void __sp_try_coalesce_prev(struct sp_reg_root *r, struct sp_mem *m)
+{
+	while(m){
+		if(!m || is_region_used(m->flags))
+			return;
+
+		struct sp_mem *p = m->prev;
+		if(!p || is_region_used(p->flags))
+			return;
+
+		m->start = p->start;
+		m->prev = p->prev;
+
+		if(m->prev)
+			m->prev->next = m;
+
+		sp_remove(&sp_root(r->free_regions), &p->sp_n);
+		free_mem_node(p);
+
+		m = m->prev;
+	}
+}
+
+static void __sp_try_coalesce_next(struct sp_reg_root *r, struct sp_mem *m)
+{
+	while(m){
+		if(!m || is_region_used(m->flags))
+			return;
+
+		struct sp_mem *n = m->next;
+		if(!n || is_region_used(n->flags))
+			return;
+
+		m->end = n->end;
+		m->next = n->next;
+
+		if(m->next)
+			m->next->prev = m;
+
+		sp_remove(&sp_root(r->free_regions), &n->sp_n);
+		free_mem_node(n);
+
+		m = m->next;
+	}
+}
+
+static void sp_mem_try_coalesce(struct sp_reg_root *r, struct sp_mem *m)
+{
+	__sp_try_coalesce_prev(r, m);
+	__sp_try_coalesce_next(r, m);
+}
+
+stat_t free_region(struct sp_reg_root *r, vm_t start)
+{
+	/* addr not aligned to page boundary, corrupted or incorrect pointer */
+	if(!aligned(start, BASE_PAGE_SIZE))
+		return ERR_ALIGN;
+
+	struct sp_mem *m = sp_used_find(r, __page(start));
+	if(!m)
+		return ERR_NF;
+
+	sp_remove(&sp_root(r->used_regions), &m->sp_n);
+	mark_region_unused(m->flags);
+
+	sp_mem_try_coalesce(r, m);
+	sp_free_insert_region(r, m);
+	return OK;
+}
+
+void set_uvmem_size(size_t s)
+{
+	__uvmem_size = s;
+}
+
+size_t uvmem_size()
+{
+	return __uvmem_size;
+}
+
+/* assuming start is chosen to start on an aligned border, this should choose
+ * the 'optimal' fit for the mapping.
+ *
+ * NOTE: not actually optimal, this doesn't bother to go through possible
+ * permutations etc. which would be slow and I don't want to implement it.
+ */
+vm_t map_fill_region(struct vm_branch *b,
+		stat_t (*vmem_handler)(struct vm_branch *, pm_t *, vm_t, uint8_t, enum mm_order),
+		pm_t offset, vm_t start, size_t bytes, uint8_t flags)
+{
+	pm_t runner = __page(start);
+	size_t pages = __pages(bytes);
+	enum mm_order top = __mm_max_order;
+
+	/* actual start might not be the same as the user specified start */
+	start = __addr(runner);
+
+	for(; pages; top--){
+		size_t o_size = __o_size(top);
+		size_t o_pages = __pages(o_size);
+
+		/* NULL does pass this check, so technically all NULL pages are
+		 * aligned, but they're caught in the while expr so this should
+		 * work even if someone tries to map NULL */
+		if(!aligned(runner, o_pages))
+			continue;
+
+		while(pages >= o_pages){
+			int res = vmem_handler(b, &offset, __addr(runner), flags, top);
+			if(res > 0)
+				break;
+
+			if(res < 0)
+				return 0;
+
+			pages -= o_pages;
+			runner += o_pages;
+		}
+	}
+
+	return start;
+}