diff options
Diffstat (limited to 'kernel/syscall.c')
| -rw-r--r-- | kernel/syscall.c | 99 |
1 files changed, 98 insertions, 1 deletions
diff --git a/kernel/syscall.c b/kernel/syscall.c index 44ebfa0..8ed7631 100644 --- a/kernel/syscall.c +++ b/kernel/syscall.c @@ -3,6 +3,7 @@ #include <comus/user.h> #include <comus/cpu.h> #include <comus/syscalls.h> +#include <comus/input.h> #include <comus/drivers/acpi.h> #include <comus/drivers/gpu.h> #include <comus/drivers/pit.h> @@ -482,6 +483,99 @@ static int sys_ticks(void) return 0; } +static int sys_popsharedmem(void) +{ + RET(void *, res_mem); + *res_mem = NULL; + + if (pcb->shared_mem == NULL) { + return 1; + } + + struct pcb *const sharer = pcb_find_pid(pcb->shared_mem_source); + if (sharer == NULL) { + // process died or something since sharing + pcb->shared_mem = NULL; + return 1; + } + + void *result = + mem_mapaddr(pcb->memctx, mem_get_phys(sharer->memctx, pcb->shared_mem), + pcb->shared_mem, pcb->shared_mem_pages * PAGE_SIZE, + F_WRITEABLE | F_UNPRIVILEGED); + + // if (!result) { + // alert the other process that we cannot get its allocation? + // mem_free_pages(pcb->memctx, alloced); + // return 1; + // } + + *res_mem = result; + + pcb->shared_mem = NULL; + + return 0; +} + +static int sys_allocshared(void) +{ + ARG1(size_t, num_pages); + ARG2(unsigned short, otherpid); // same as pid_t + RET(void *, res_mem); + *res_mem = NULL; + assert(sizeof(unsigned short) == sizeof(pid_t), + "out of date sys_memshare syscall, pid_t changed?"); + + if (otherpid == pcb->pid || otherpid == 0) { + return 1; + } + + struct pcb *const otherpcb = pcb_find_pid(otherpid); + if (otherpcb == NULL) { + // no such target process exists + return 1; + } + if (otherpcb->shared_mem != NULL) { + // it has yet to consume the last allocshared given to it + return 1; + } + + void *alloced = + mem_alloc_pages(pcb->memctx, num_pages, F_WRITEABLE | F_UNPRIVILEGED); + + if (!alloced) { + return 1; + } + + otherpcb->shared_mem = alloced; + otherpcb->shared_mem_source = pcb->pid; + otherpcb->shared_mem_pages = num_pages; + + *res_mem = alloced; + + return 0; +} + +// NOTE: observes AND consumes the key event +static int sys_keypoll(void) +{ + ARG1(struct keycode *, keyev); + RET(int, waspressed); + + void *ouraddr = kmapuseraddr(pcb->memctx, keyev, sizeof(struct keycode)); + + if (keycode_pop(ouraddr)) { + kunmapaddr(ouraddr); + *waspressed = false; + return 0; + } + + kunmapaddr(ouraddr); + + *waspressed = true; + return 0; +} + static int sys_seek(void) { RET(long int, ret); @@ -498,6 +592,7 @@ static int sys_seek(void) return 0; } +// clang-format off static int (*syscall_tbl[N_SYSCALLS])(void) = { [SYS_exit] = sys_exit, [SYS_waitpid] = sys_waitpid, [SYS_fork] = sys_fork, [SYS_exec] = sys_exec, @@ -509,8 +604,10 @@ static int (*syscall_tbl[N_SYSCALLS])(void) = { [SYS_sleep] = sys_sleep, [SYS_brk] = sys_brk, [SYS_sbrk] = sys_sbrk, [SYS_poweroff] = sys_poweroff, [SYS_drm] = sys_drm, [SYS_ticks] = sys_ticks, - [SYS_seek] = sys_seek, + [SYS_seek] = sys_seek, [SYS_allocshared] = sys_allocshared, + [SYS_popsharedmem] = sys_popsharedmem, [SYS_keypoll] = sys_keypoll, }; +// clang-format on void syscall_handler(void) { |