diff options
| author | Alex Auvolat <alex.auvolat@ens.fr> | 2015-02-14 23:13:51 +0100 |
|---|---|---|
| committer | Alex Auvolat <alex.auvolat@ens.fr> | 2015-02-14 23:13:51 +0100 |
| commit | 817b7848dca5b7080ba53666eb2dd8f37b05453a (patch) | |
| tree | 73b5e37afe39e1bc05904685095d83a44d4bd353 /src/kernel/core/paging.c | |
| parent | 73cf3eddd480f2bd7e987c58da82c243861a5314 (diff) | |
| download | kogata-817b7848dca5b7080ba53666eb2dd8f37b05453a.tar.gz kogata-817b7848dca5b7080ba53666eb2dd8f37b05453a.zip | |
Fix mchmap. Lesson : invalid pointer dereferences happen! with unexpected results.
Diffstat (limited to 'src/kernel/core/paging.c')
| -rw-r--r-- | src/kernel/core/paging.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/src/kernel/core/paging.c b/src/kernel/core/paging.c index 69fb98f..0b46be1 100644 --- a/src/kernel/core/paging.c +++ b/src/kernel/core/paging.c @@ -7,8 +7,8 @@ #include <thread.h> #include <malloc.h> -#define PAGE_OF_ADDR(x) (((size_t)x >> PAGE_SHIFT) % N_PAGES_IN_PT) -#define PT_OF_ADDR(x) ((size_t)x >> (PAGE_SHIFT + PT_SHIFT)) +#define PAGE_OF_ADDR(x) (((size_t)(x) >> PAGE_SHIFT) % N_PAGES_IN_PT) +#define PT_OF_ADDR(x) ((size_t)(x) >> (PAGE_SHIFT + PT_SHIFT)) typedef struct page_table { uint32_t page[1024]; @@ -197,14 +197,16 @@ uint32_t pd_get_frame(void* vaddr) { } bool pd_map_page(void* vaddr, uint32_t frame_id, bool rw) { - uint32_t pt = PT_OF_ADDR(vaddr); - uint32_t page = PAGE_OF_ADDR(vaddr); + const uint32_t pt = PT_OF_ADDR(vaddr); + const uint32_t page = PAGE_OF_ADDR(vaddr); ASSERT((size_t)vaddr < PD_MIRROR_ADDR); - pagedir_t *pdd = ((size_t)vaddr >= K_HIGHHALF_ADDR || current_thread == 0 - ? &kernel_pd_d : current_thread->current_pd_d); - pagetable_t *pd = ((size_t)vaddr >= K_HIGHHALF_ADDR ? &kernel_pd : current_pd); + bool on_kernel_pd = (size_t)vaddr >= K_HIGHHALF_ADDR || current_thread == 0; + + pagedir_t *pdd = (on_kernel_pd ? &kernel_pd_d : current_thread->current_pd_d); + pagetable_t *pd = (on_kernel_pd ? &kernel_pd : current_pd); + mutex_lock(&pdd->mutex); if (!(pd->page[pt] & PTE_PRESENT)) { |