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-rw-r--r--common/vmem.c378
1 files changed, 0 insertions, 378 deletions
diff --git a/common/vmem.c b/common/vmem.c
deleted file mode 100644
index f52f43e..0000000
--- a/common/vmem.c
+++ /dev/null
@@ -1,378 +0,0 @@
-/* SPDX-License-Identifier: copyleft-next-0.3.1 */
-/* Copyright 2021 - 2022, Kim Kuparinen < kimi.h.kuparinen@gmail.com > */
-
-/**
- * @file vmem.c
- * Virtual memory handling, mainly userspace virtual memory.
- */
-
-#include <kmi/mem_regions.h>
-#include <kmi/assert.h>
-#include <kmi/string.h>
-#include <kmi/debug.h>
-#include <kmi/bits.h>
-#include <kmi/vmem.h>
-#include <arch/vmem.h>
-
-stat_t init_uvmem(struct tcb *t, vm_t base, vm_t top)
-{
- return init_region(&t->sp_r, base, top);
-}
-
-/**
- * Clone process memory region.
- *
- * @param d Destination tcb.
- * @param s Source tcb.
- * @param m Memory region to clone.
- * @return \ref ERR_MISC if clone failed, otherwise \ref OK.
- *
- * @todo check shared memory regions.
- */
-static stat_t __clone_mapped_region(struct tcb *d, struct tcb *s,
- struct mem_region *m)
-{
- vm_t start = m->start * order_size(BASE_PAGE);
- vm_t end = m->end * order_size(BASE_PAGE);
-
- size_t size = end - start, actual_size = 0;
- vm_t va = alloc_fixed_region(&d->sp_r, start, size,
- &actual_size, m->flags);
-
- catastrophic_assert(va == start);
-
- if (!copy_allocd_region(d->proc.vmem, va, size, m->flags, s->proc.vmem))
- return ERR_MISC;
-
- return OK;
-}
-
-/**
- * Unmap and free private memory region.
- *
- * @param t Current thread.
- * @param m Memory region to free.
- * @return \see unmap_freed_region().
- */
-static stat_t __free_mapped_private_region(struct tcb *t, struct mem_region *m)
-{
- stat_t status = OK;
- pm_t start = __addr(m->start);
- pm_t end = __addr(m->end);
- if (!unmap_freed_region(t->proc.vmem, start, end - start, m->flags,
- &status))
- return ERR_MISC;
-
- return status;
-}
-
-/**
- * Check whether process associated with shared memory is still using it.
- *
- * @param pid Process to check.
- * @param start Start of memory region
- * @return \ref true if it is still in use, \ref false otherwise.
- */
-static bool __proc_has_region(id_t pid, vm_t start)
-{
- /** @todo this has a slight potential to have a race condition, where
- * both threads want to free the same shared region at the same time. */
- struct tcb *p = get_tcb(pid);
- if (!p)
- return false;
-
- struct mem_region *m = find_used_region(&p->sp_r, start);
- if (!m)
- return false;
-
- return true;
-}
-
-/**
- * Unmap shared region and free associated physical pages if they're not being
- * used by the other process.
- *
- * @param t Current thread.
- * @param m Memory region to free.
- * @return \see unmap_vpage().
- */
-static stat_t __free_mapped_shared_region(struct tcb *t, struct mem_region *m)
-{
- vm_t start = __addr(m->start);
- bool in_use = __proc_has_region(m->pid, m->alt_va);
-
- size_t osize = order_size(BASE_PAGE);
- size_t pages = m->start - m->end;
-
- stat_t status = OK;
- for (size_t i = 0; i < pages; ++i) {
- vm_t va = start + i * osize;
-
- pm_t pa = 0;
- stat_vpage(t->proc.vmem, va, &pa, 0, 0);
- status = unmap_vpage(t->proc.vmem, va);
-
- if (!in_use)
- free_page(pa, BASE_PAGE);
- }
-
- return status;
-}
-
-/**
- * Convenience function for freeing mapped regions.
- *
- * @param t Thread to work in.
- * @param m Memory region to free.
- * @return \ref OK
- */
-static stat_t __free_mapped_region(struct tcb *t, struct mem_region *m)
-{
- if (m->pid != 0)
- return __free_mapped_shared_region(t, m);
-
- return __free_mapped_private_region(t, m);
-}
-
-stat_t clear_uvmem(struct tcb *t)
-{
- struct mem_region *m = find_first_region(&t->sp_r);
- while (m) {
- if (!is_region_kept(m))
- __free_mapped_region(t, m);
-
- m = m->next;
- }
-
- return OK;
-}
-
-stat_t purge_uvmem(struct tcb *t)
-{
- struct mem_region *m = find_first_region(&t->sp_r);
- while (m) {
- __free_mapped_region(t, m);
- m = m->next;
- }
-
- return OK;
-}
-
-stat_t destroy_uvmem(struct tcb *t)
-{
- /* force clear all regions */
- purge_uvmem(t);
- /* destroy region tree itself */
- return destroy_region(&t->sp_r);
-}
-
-stat_t clone_mem_regions(struct tcb *d, struct tcb *s)
-{
- /** @todo implement some way to only iterate used regions, this loops
- * through all regions which is likely a slight bit slower. */
- struct mem_region *m = find_first_region(&s->sp_r);
- while (m) {
- if (is_region_used(m))
- __clone_mapped_region(d, s, m);
-
- m = m->next;
- }
-
- return OK;
-}
-
-vm_t alloc_uvmem(struct tcb *t, size_t size, vmflags_t flags)
-{
- /* t exists and is the process tcb of the current process */
- hard_assert(t && is_proc(t), ERR_INVAL);
-
- stat_t status = OK;
- const vm_t v = alloc_region(&t->sp_r, size, &size, flags);
- const vm_t w = map_allocd_region(t->proc.vmem, v, size, flags, &status);
- return w;
-}
-
-vm_t alloc_uvpage(struct tcb *t, size_t size, vmflags_t flags, size_t *asize,
- pm_t *paddr)
-{
- hard_assert(t && is_proc(t), ERR_INVAL);
-
- enum mm_order order = nearest_order(size);
- size_t actual_size = order_size(order);
- stat_t status = OK;
-
- const vm_t v = alloc_region(&t->sp_r, size, &size, flags);
- const vm_t w = __addr(__page(v));
-
- pm_t addr = alloc_page(order);
- /** @todo should free region */
- if (!addr)
- return NULL;
-
- status = map_vpage(t->proc.vmem, addr, w, flags, order);
- if (status)
- return NULL;
-
- if (asize)
- *asize = actual_size;
-
- if (paddr)
- *paddr = addr;
-
- return w;
-}
-
-vm_t alloc_fixed_uvmem(struct tcb *t, vm_t start, size_t size, vmflags_t flags)
-{
- hard_assert(t && is_proc(t), ERR_INVAL);
-
- stat_t status = OK;
- const vm_t v = alloc_fixed_region(&t->sp_r, start, size, &size, flags);
- const vm_t w = map_allocd_region(t->proc.vmem, v, size, flags, &status);
- return w;
-}
-
-/* free_shared_uvmem shouldn't be needed, likely to work with free_uvmem */
-stat_t alloc_shared_uvmem(struct tcb *s, struct tcb *c,
- size_t size, vmflags_t sflags, vmflags_t cflags,
- vm_t *sstart, vm_t *cstart)
-{
- hard_assert(sstart, ERR_INVAL);
- hard_assert(cstart, ERR_INVAL);
- hard_assert(s && is_proc(s), ERR_INVAL);
- hard_assert(c && is_proc(c), ERR_INVAL);
-
- size_t ssize, csize;
- vm_t sv = alloc_shared_region(&s->sp_r, size, &ssize, sflags, c->rid);
- vm_t cv = alloc_shared_region(&c->sp_r, size, &csize, cflags, s->rid);
-
- /* not exactly optimal but good enough for now, I can start worrying
- * about hyperoptimizations whenever. */
- set_alt_region_addr(&s->sp_r, sv, cv);
- set_alt_region_addr(&c->sp_r, cv, sv);
-
- if (csize != ssize) {
- /** @todo cleanup, better errors? */
- return ERR_INVAL;
- }
-
- stat_t cstatus = OK, sstatus = OK;
- size_t osize = order_size(BASE_PAGE);
- size_t pages = ssize / osize;
- for (size_t i = 0; i < pages; ++i) {
- pm_t p = alloc_page(BASE_PAGE);
- sstatus = map_vpage(s->proc.vmem, p, sv + i * osize, sflags,
- BASE_PAGE);
- cstatus = map_vpage(c->proc.vmem, p, cv + i * osize, cflags,
- BASE_PAGE);
- }
-
- *sstart = sv;
- *cstart = cv;
-
- if (sstatus)
- return sstatus;
-
- if (cstatus)
- return cstatus;
-
- return OK;
-}
-
-stat_t free_uvmem(struct tcb *r, vm_t va)
-{
- /** \todo assume tcb is root tcb? */
- struct mem_region *m = find_used_region(&r->sp_r, va);
- if (!m)
- return ERR_NF;
-
- stat_t status = __free_mapped_region(r, m);
- if (status)
- return ERR_MISC;
-
- return free_known_region(&r->sp_r, m);
-}
-
-stat_t alloc_uvmem_wrapper(struct vmem *b, pm_t *offset, vm_t vaddr,
- vmflags_t flags, enum mm_order order, void *data)
-{
- *offset = alloc_page(order);
- if (!*offset)
- return INFO_TRGN; /* try again */
-
- stat_t *status = (stat_t *)data, ret;
- ret = map_vpage(b, *offset, vaddr, flags, order);
- if (status)
- *status = ret;
-
- return ret;
-}
-
-stat_t alloc_shared_wrapper(struct vmem *b, pm_t *offset, vm_t vaddr,
- vmflags_t flags, enum mm_order order, void *data)
-{
- if (order != MM_O0)
- return INFO_TRGN;
-
- *offset = alloc_page(MM_O0);
-
- stat_t *status = (stat_t *)data, ret;
- ret = map_vpage(b, *offset, vaddr, flags, order);
- if (status)
- *status = ret;
-
- return ret;
-}
-
-stat_t copy_allocd_wrapper(struct vmem *b, pm_t *offset, vm_t vaddr,
- vmflags_t flags, enum mm_order order, void *data)
-{
- struct vmem *s = (struct vmem *)data;
-
- pm_t paddr = 0;
- enum mm_order v_order = 0;
- stat_vpage(s, vaddr, &paddr, &v_order, 0);
- /** @todo what if we could combine multiple pages into one in the new
- * process? */
- if (order > v_order)
- return INFO_TRGN;
-
- pm_t new_page = alloc_page(order);
- if (!new_page)
- return INFO_TRGN;
-
- map_vpage(b, new_page, vaddr, flags, order);
- memcpy((void *)new_page, (void *)(paddr + *offset), order_size(order));
-
- if (v_order > order)
- *offset += order_size(order);
- else
- *offset = 0;
-
- return OK;
-}
-
-stat_t free_uvmem_wrapper(struct vmem *b, pm_t *offset, vm_t vaddr,
- vmflags_t flags, enum mm_order order, void *data)
-{
- UNUSED(flags);
- UNUSED(offset);
-
- pm_t paddr = 0;
- enum mm_order v_order = 0;
- stat_vpage(b, vaddr, &paddr, &v_order, 0);
- if (order != v_order)
- return INFO_TRGN;
-
- /** @todo we might need to cause an ipi to flush the tlb for other
- * cores */
-
- stat_t *status = (stat_t *)data, ret;
- ret = unmap_vpage(b, vaddr);
- if (status)
- *status = ret;
-
- free_page(order, paddr);
-
- return ret;
-}
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