diff options
Diffstat (limited to 'src/kernel/syscalls.c')
| -rw-r--r-- | src/kernel/syscalls.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c index 4d64d32..540611e 100644 --- a/src/kernel/syscalls.c +++ b/src/kernel/syscalls.c @@ -250,34 +250,42 @@ int _syscall_fs_respond(char __user *buf, int ret) { SYSCALL_RETURN(0); } -int _syscall_memflag(void __user *addr, size_t len, int flags) { - userptr_t goal = addr + len; +void __user *_syscall_memflag(void __user *addr, size_t len, int flags) { struct pagedir *pages = process_current->pages; void *phys; - addr = (userptr_t)((int __force)addr & ~PAGE_MASK); // align to page boundary - for (; addr < goal; addr += PAGE_SIZE) { - if (pagedir_iskern(pages, addr)) { + + if (flags & MEMFLAG_FINDFREE) { + addr = pagedir_findfree(pages, addr, len); + if (!(flags & MEMFLAG_PRESENT)) goto ret; + } + + + for (userptr_t iter = addr; iter < addr + len; iter += PAGE_SIZE) { + if (pagedir_iskern(pages, iter)) { // TODO reflect failure in return value continue; } - phys = pagedir_virt2phys(pages, addr, false, false); + phys = pagedir_virt2phys(pages, iter, false, false); if (!(flags & MEMFLAG_PRESENT)) { if (phys) - page_free(pagedir_unmap(pages, addr), 1); + page_free(pagedir_unmap(pages, iter), 1); continue; } if (!phys) { phys = page_alloc(1); memset(phys, 0, PAGE_SIZE); // TODO somehow test this - pagedir_map(pages, addr, phys, true, true); + pagedir_map(pages, iter, phys, true, true); } } - SYSCALL_RETURN(-1); +ret: // the macro is too stupid to handle returning pointers + assert(process_current->state == PS_RUNNING); // TODO move to regs_savereturn + regs_savereturn(&process_current->regs, (uintptr_t)addr); + return addr; } int _syscall(int num, int a, int b, int c, int d) { @@ -303,7 +311,8 @@ int _syscall(int num, int a, int b, int c, int d) { case _SYSCALL_FS_RESPOND: return _syscall_fs_respond((userptr_t)a, b); case _SYSCALL_MEMFLAG: - return _syscall_memflag((userptr_t)a, b, c); + _syscall_memflag((userptr_t)a, b, c); + return -1; // unused anyways default: kprintf("unknown syscall "); panic_unimplemented(); // TODO fail gracefully |