#include <linux/slab.h>
#include <linux/io.h>
#include <linux/log2.h>
+#include <linux/rcupdate.h>
+#include <linux/cred.h>
#include "vas.h"
vas_release_window_id(&vinst->ida, winid);
}
-struct vas_window *vas_window_alloc(struct vas_instance *vinst)
+static struct vas_window *vas_window_alloc(struct vas_instance *vinst)
{
int winid;
struct vas_window *window;
return ERR_PTR(-ENOMEM);
}
+/*
+ * Get the VAS receive window associated with NX engine identified
+ * by @cop and if applicable, @pswid.
+ *
+ * See also function header of set_vinst_win().
+ */
+struct vas_window *get_vinst_rxwin(struct vas_instance *vinst,
+ enum vas_cop_type cop, u32 pswid)
+{
+ struct vas_window *rxwin;
+
+ mutex_lock(&vinst->mutex);
+
+ if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI)
+ rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);
+ else
+ rxwin = ERR_PTR(-EINVAL);
+
+ if (!IS_ERR(rxwin))
+ atomic_inc(&rxwin->num_txwins);
+
+ mutex_unlock(&vinst->mutex);
+
+ return rxwin;
+}
+
+/*
+ * We have two tables of windows in a VAS instance. The first one,
+ * ->windows[], contains all the windows in the instance and allows
+ * looking up a window by its id. It is used to look up send windows
+ * during fault handling and receive windows when pairing user space
+ * send/receive windows.
+ *
+ * The second table, ->rxwin[], contains receive windows that are
+ * associated with NX engines. This table has VAS_COP_TYPE_MAX
+ * entries and is used to look up a receive window by its
+ * coprocessor type.
+ *
+ * Here, we save @window in the ->windows[] table. If it is a receive
+ * window, we also save the window in the ->rxwin[] table.
+ */
+static void set_vinst_win(struct vas_instance *vinst,
+ struct vas_window *window)
+{
+ int id = window->winid;
+
+ mutex_lock(&vinst->mutex);
+
+ /*
+ * There should only be one receive window for a coprocessor type
+ * unless its a user (FTW) window.
+ */
+ if (!window->user_win && !window->tx_win) {
+ WARN_ON_ONCE(vinst->rxwin[window->cop]);
+ vinst->rxwin[window->cop] = window;
+ }
+
+ WARN_ON_ONCE(vinst->windows[id] != NULL);
+ vinst->windows[id] = window;
+
+ mutex_unlock(&vinst->mutex);
+}
+
+/*
+ * Clear this window from the table(s) of windows for this VAS instance.
+ * See also function header of set_vinst_win().
+ */
+void clear_vinst_win(struct vas_window *window)
+{
+ int id = window->winid;
+ struct vas_instance *vinst = window->vinst;
+
+ mutex_lock(&vinst->mutex);
+
+ if (!window->user_win && !window->tx_win) {
+ WARN_ON_ONCE(!vinst->rxwin[window->cop]);
+ vinst->rxwin[window->cop] = NULL;
+ }
+
+ WARN_ON_ONCE(vinst->windows[id] != window);
+ vinst->windows[id] = NULL;
+
+ mutex_unlock(&vinst->mutex);
+}
+
+static void init_winctx_for_rxwin(struct vas_window *rxwin,
+ struct vas_rx_win_attr *rxattr,
+ struct vas_winctx *winctx)
+{
+ /*
+ * We first zero (memset()) all fields and only set non-zero fields.
+ * Following fields are 0/false but maybe deserve a comment:
+ *
+ * ->notify_os_intr_reg In powerNV, send intrs to HV
+ * ->notify_disable False for NX windows
+ * ->intr_disable False for Fault Windows
+ * ->xtra_write False for NX windows
+ * ->notify_early NA for NX windows
+ * ->rsvd_txbuf_count NA for Rx windows
+ * ->lpid, ->pid, ->tid NA for Rx windows
+ */
+
+ memset(winctx, 0, sizeof(struct vas_winctx));
+
+ winctx->rx_fifo = rxattr->rx_fifo;
+ winctx->rx_fifo_size = rxattr->rx_fifo_size;
+ winctx->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+ winctx->pin_win = rxattr->pin_win;
+
+ winctx->nx_win = rxattr->nx_win;
+ winctx->fault_win = rxattr->fault_win;
+ winctx->rx_word_mode = rxattr->rx_win_ord_mode;
+ winctx->tx_word_mode = rxattr->tx_win_ord_mode;
+ winctx->rx_wcred_mode = rxattr->rx_wcred_mode;
+ winctx->tx_wcred_mode = rxattr->tx_wcred_mode;
+
+ if (winctx->nx_win) {
+ winctx->data_stamp = true;
+ winctx->intr_disable = true;
+ winctx->pin_win = true;
+
+ WARN_ON_ONCE(winctx->fault_win);
+ WARN_ON_ONCE(!winctx->rx_word_mode);
+ WARN_ON_ONCE(!winctx->tx_word_mode);
+ WARN_ON_ONCE(winctx->notify_after_count);
+ } else if (winctx->fault_win) {
+ winctx->notify_disable = true;
+ } else if (winctx->user_win) {
+ /*
+ * Section 1.8.1 Low Latency Core-Core Wake up of
+ * the VAS workbook:
+ *
+ * - disable credit checks ([tr]x_wcred_mode = false)
+ * - disable FIFO writes
+ * - enable ASB_Notify, disable interrupt
+ */
+ winctx->fifo_disable = true;
+ winctx->intr_disable = true;
+ winctx->rx_fifo = NULL;
+ }
+
+ winctx->lnotify_lpid = rxattr->lnotify_lpid;
+ winctx->lnotify_pid = rxattr->lnotify_pid;
+ winctx->lnotify_tid = rxattr->lnotify_tid;
+ winctx->pswid = rxattr->pswid;
+ winctx->dma_type = VAS_DMA_TYPE_INJECT;
+ winctx->tc_mode = rxattr->tc_mode;
+
+ winctx->min_scope = VAS_SCOPE_LOCAL;
+ winctx->max_scope = VAS_SCOPE_VECTORED_GROUP;
+}
+
+static bool rx_win_args_valid(enum vas_cop_type cop,
+ struct vas_rx_win_attr *attr)
+{
+ dump_rx_win_attr(attr);
+
+ if (cop >= VAS_COP_TYPE_MAX)
+ return false;
+
+ if (cop != VAS_COP_TYPE_FTW &&
+ attr->rx_fifo_size < VAS_RX_FIFO_SIZE_MIN)
+ return false;
+
+ if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX)
+ return false;
+
+ if (attr->nx_win) {
+ /* cannot be fault or user window if it is nx */
+ if (attr->fault_win || attr->user_win)
+ return false;
+ /*
+ * Section 3.1.4.32: NX Windows must not disable notification,
+ * and must not enable interrupts or early notification.
+ */
+ if (attr->notify_disable || !attr->intr_disable ||
+ attr->notify_early)
+ return false;
+ } else if (attr->fault_win) {
+ /* cannot be both fault and user window */
+ if (attr->user_win)
+ return false;
+
+ /*
+ * Section 3.1.4.32: Fault windows must disable notification
+ * but not interrupts.
+ */
+ if (!attr->notify_disable || attr->intr_disable)
+ return false;
+
+ } else if (attr->user_win) {
+ /*
+ * User receive windows are only for fast-thread-wakeup
+ * (FTW). They don't need a FIFO and must disable interrupts
+ */
+ if (attr->rx_fifo || attr->rx_fifo_size || !attr->intr_disable)
+ return false;
+ } else {
+ /* Rx window must be one of NX or Fault or User window. */
+ return false;
+ }
+
+ return true;
+}
+
+void vas_init_rx_win_attr(struct vas_rx_win_attr *rxattr, enum vas_cop_type cop)
+{
+ memset(rxattr, 0, sizeof(*rxattr));
+
+ if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI) {
+ rxattr->pin_win = true;
+ rxattr->nx_win = true;
+ rxattr->fault_win = false;
+ rxattr->intr_disable = true;
+ rxattr->rx_wcred_mode = true;
+ rxattr->tx_wcred_mode = true;
+ rxattr->rx_win_ord_mode = true;
+ rxattr->tx_win_ord_mode = true;
+ } else if (cop == VAS_COP_TYPE_FAULT) {
+ rxattr->pin_win = true;
+ rxattr->fault_win = true;
+ rxattr->notify_disable = true;
+ rxattr->rx_wcred_mode = true;
+ rxattr->tx_wcred_mode = true;
+ rxattr->rx_win_ord_mode = true;
+ rxattr->tx_win_ord_mode = true;
+ } else if (cop == VAS_COP_TYPE_FTW) {
+ rxattr->user_win = true;
+ rxattr->intr_disable = true;
+
+ /*
+ * As noted in the VAS Workbook we disable credit checks.
+ * If we enable credit checks in the future, we must also
+ * implement a mechanism to return the user credits or new
+ * paste operations will fail.
+ */
+ }
+}
+EXPORT_SYMBOL_GPL(vas_init_rx_win_attr);
+
+struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
+ struct vas_rx_win_attr *rxattr)
+{
+ struct vas_window *rxwin;
+ struct vas_winctx winctx;
+ struct vas_instance *vinst;
+
+ if (!rx_win_args_valid(cop, rxattr))
+ return ERR_PTR(-EINVAL);
+
+ vinst = find_vas_instance(vasid);
+ if (!vinst) {
+ pr_devel("vasid %d not found!\n", vasid);
+ return ERR_PTR(-EINVAL);
+ }
+ pr_devel("Found instance %d\n", vasid);
+
+ rxwin = vas_window_alloc(vinst);
+ if (IS_ERR(rxwin)) {
+ pr_devel("Unable to allocate memory for Rx window\n");
+ return rxwin;
+ }
+
+ rxwin->tx_win = false;
+ rxwin->nx_win = rxattr->nx_win;
+ rxwin->user_win = rxattr->user_win;
+ rxwin->cop = cop;
+ if (rxattr->user_win)
+ rxwin->pid = task_pid_vnr(current);
+
+ init_winctx_for_rxwin(rxwin, rxattr, &winctx);
+ init_winctx_regs(rxwin, &winctx);
+
+ set_vinst_win(vinst, rxwin);
+
+ return rxwin;
+}
+EXPORT_SYMBOL_GPL(vas_rx_win_open);
+
/* stub for now */
int vas_win_close(struct vas_window *window)
{
projects / mirror_ubuntu-jammy-kernel.git / commitdiff