#include <linux/log2.h>
#include <linux/rcupdate.h>
#include <linux/cred.h>
+#include <linux/sched/mm.h>
+#include <linux/mmu_context.h>
#include <asm/switch_to.h>
#include <asm/ppc-opcode.h>
#include "vas.h"
rxwin->user_win = rxattr->user_win;
rxwin->cop = cop;
rxwin->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
- if (rxattr->user_win)
- rxwin->pid = task_pid_vnr(current);
init_winctx_for_rxwin(rxwin, rxattr, &winctx);
init_winctx_regs(rxwin, &winctx);
txwin->tx_win = 1;
txwin->rxwin = rxwin;
txwin->nx_win = txwin->rxwin->nx_win;
- txwin->pid = attr->pid;
txwin->user_win = attr->user_win;
txwin->wcreds_max = attr->wcreds_max ?: VAS_WCREDS_DEFAULT;
rc = set_thread_uses_vas();
if (rc)
goto free_window;
+
+ /*
+ * Window opened by a child thread may not be closed when
+ * it exits. So take reference to its pid and release it
+ * when the window is free by parent thread.
+ * Acquire a reference to the task's pid to make sure
+ * pid will not be re-used - needed only for multithread
+ * applications.
+ */
+ txwin->pid = get_task_pid(current, PIDTYPE_PID);
+ /*
+ * Acquire a reference to the task's mm.
+ */
+ txwin->mm = get_task_mm(current);
+
+ if (!txwin->mm) {
+ put_pid(txwin->pid);
+ pr_err("VAS: pid(%d): mm_struct is not found\n",
+ current->pid);
+ rc = -EPERM;
+ goto free_window;
+ }
+
+ mmgrab(txwin->mm);
+ mmput(txwin->mm);
+ mm_context_add_copro(txwin->mm);
+ /*
+ * Process closes window during exit. In the case of
+ * multithread application, the child thread can open
+ * window and can exit without closing it. Expects parent
+ * thread to use and close the window. So do not need
+ * to take pid reference for parent thread.
+ */
+ txwin->tgid = find_get_pid(task_tgid_vnr(current));
}
set_vinst_win(vinst, txwin);
poll_window_castout(window);
/* if send window, drop reference to matching receive window */
- if (window->tx_win)
+ if (window->tx_win) {
+ if (window->user_win) {
+ /* Drop references to pid and mm */
+ put_pid(window->pid);
+ if (window->mm) {
+ mm_context_remove_copro(window->mm);
+ mmdrop(window->mm);
+ }
+ }
put_rx_win(window->rxwin);
+ }
vas_window_free(window);
bool user_win; /* True if user space window */
void *hvwc_map; /* HV window context */
void *uwc_map; /* OS/User window context */
- pid_t pid; /* Linux process id of owner */
+ struct pid *pid; /* Linux process id of owner */
+ struct pid *tgid; /* Thread group ID of owner */
+ struct mm_struct *mm; /* Linux process mm_struct */
int wcreds_max; /* Window credits */
char *dbgname;
extern void vas_window_free_dbgdir(struct vas_window *win);
extern int vas_setup_fault_window(struct vas_instance *vinst);
+static inline int vas_window_pid(struct vas_window *window)
+{
+ return pid_vnr(window->pid);
+}
+
static inline void vas_log_write(struct vas_window *win, char *name,
void *regptr, u64 val)
{