Merge tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "A bit of a small release, I suspect in part due to me travelling for
  KS. But my backlog of patches to review is smaller than usual, so I
  think in part folks just didn't send as much this cycle.

  Non-highlights:

   - Five fixes for the >128T address space handling, both to fix bugs
     in our implementation and to bring the semantics exactly into line
     with x86.

  Highlights:

   - Support for a new OPAL call on bare metal machines which gives us a
     true NMI (ie. is not masked by MSR[EE]=0) for debugging etc.

   - Support for Power9 DD2 in the CXL driver.

   - Improvements to machine check handling so that uncorrectable errors
     can be reported into the generic memory_failure() machinery.

   - Some fixes and improvements for VPHN, which is used under PowerVM
     to notify the Linux partition of topology changes.

   - Plumbing to enable TM (transactional memory) without suspend on
     some Power9 processors (PPC_FEATURE2_HTM_NO_SUSPEND).

   - Support for emulating vector loads form cache-inhibited memory, on
     some Power9 revisions.

   - Disable the fast-endian switch "syscall" by default (behind a
     CONFIG), we believe it has never had any users.

   - A major rework of the API drivers use when initiating and waiting
     for long running operations performed by OPAL firmware, and changes
     to the powernv_flash driver to use the new API.

   - Several fixes for the handling of FP/VMX/VSX while processes are
     using transactional memory.

   - Optimisations of TLB range flushes when using the radix MMU on
     Power9.

   - Improvements to the VAS facility used to access coprocessors on
     Power9, and related improvements to the way the NX crypto driver
     handles requests.

   - Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit.

  Thanks to: Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew
  Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin
  Herrenschmidt, Breno Leitao, Christophe Leroy, Christophe Lombard,
  Cyril Bur, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven,
  Guilherme G. Piccoli, Gustavo Romero, Haren Myneni, Joel Stanley,
  Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami Hiramatsu,
  Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao,
  Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia
  Franco de Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee,
  Shriya, Stephen Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel
  Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, and William A.
  Kennington III"

* tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (151 commits)
  powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature
  powerpc/64s: Fix masking of SRR1 bits on instruction fault
  powerpc/64s: mm_context.addr_limit is only used on hash
  powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation
  powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary
  powerpc/64s/hash: Fix fork() with 512TB process address space
  powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation
  powerpc/64s/hash: Fix 512T hint detection to use >= 128T
  powerpc: Fix DABR match on hash based systems
  powerpc/signal: Properly handle return value from uprobe_deny_signal()
  powerpc/fadump: use kstrtoint to handle sysfs store
  powerpc/lib: Implement UACCESS_FLUSHCACHE API
  powerpc/lib: Implement PMEM API
  powerpc/powernv/npu: Don't explicitly flush nmmu tlb
  powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm()
  powerpc/powernv/idle: Round up latency and residency values
  powerpc/kprobes: refactor kprobe_lookup_name for safer string operations
  powerpc/kprobes: Blacklist emulate_update_regs() from kprobes
  powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace
  powerpc/kprobes: Disable preemption before invoking probe handler for optprobes
  ...

1 files changed, 198 insertions, 44 deletions

diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c
index 5aae845b8cd9..2b3eb01ab110 100644
--- a/arch/powerpc/platforms/powernv/vas-window.c
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -16,7 +16,8 @@
 #include <linux/log2.h>
 #include <linux/rcupdate.h>
 #include <linux/cred.h>
-
+#include <asm/switch_to.h>
+#include <asm/ppc-opcode.h>
 #include "vas.h"
 #include "copy-paste.h"
 
@@ -40,6 +41,16 @@ static void compute_paste_address(struct vas_window *window, u64 *addr, int *len
 	pr_debug("Txwin #%d: Paste addr 0x%llx\n", winid, *addr);
 }
 
+u64 vas_win_paste_addr(struct vas_window *win)
+{
+	u64 addr;
+
+	compute_paste_address(win, &addr, NULL);
+
+	return addr;
+}
+EXPORT_SYMBOL(vas_win_paste_addr);
+
 static inline void get_hvwc_mmio_bar(struct vas_window *window,
 			u64 *start, int *len)
 {
@@ -145,23 +156,37 @@ static void unmap_paste_region(struct vas_window *window)
 }
 
 /*
- * Unmap the MMIO regions for a window.
+ * Unmap the MMIO regions for a window. Hold the vas_mutex so we don't
+ * unmap when the window's debugfs dir is in use. This serializes close
+ * of a window even on another VAS instance but since its not a critical
+ * path, just minimize the time we hold the mutex for now. We can add
+ * a per-instance mutex later if necessary.
  */
 static void unmap_winctx_mmio_bars(struct vas_window *window)
 {
 	int len;
+	void *uwc_map;
+	void *hvwc_map;
 	u64 busaddr_start;
 
-	if (window->hvwc_map) {
+	mutex_lock(&vas_mutex);
+
+	hvwc_map = window->hvwc_map;
+	window->hvwc_map = NULL;
+
+	uwc_map = window->uwc_map;
+	window->uwc_map = NULL;
+
+	mutex_unlock(&vas_mutex);
+
+	if (hvwc_map) {
 		get_hvwc_mmio_bar(window, &busaddr_start, &len);
-		unmap_region(window->hvwc_map, busaddr_start, len);
-		window->hvwc_map = NULL;
+		unmap_region(hvwc_map, busaddr_start, len);
 	}
 
-	if (window->uwc_map) {
+	if (uwc_map) {
 		get_uwc_mmio_bar(window, &busaddr_start, &len);
-		unmap_region(window->uwc_map, busaddr_start, len);
-		window->uwc_map = NULL;
+		unmap_region(uwc_map, busaddr_start, len);
 	}
 }
 
@@ -528,6 +553,9 @@ static void vas_window_free(struct vas_window *window)
 	struct vas_instance *vinst = window->vinst;
 
 	unmap_winctx_mmio_bars(window);
+
+	vas_window_free_dbgdir(window);
+
 	kfree(window);
 
 	vas_release_window_id(&vinst->ida, winid);
@@ -552,6 +580,8 @@ static struct vas_window *vas_window_alloc(struct vas_instance *vinst)
 	if (map_winctx_mmio_bars(window))
 		goto out_free;
 
+	vas_window_init_dbgdir(window);
+
 	return window;
 
 out_free:
@@ -569,6 +599,32 @@ static void put_rx_win(struct vas_window *rxwin)
 }
 
 /*
+ * Find the user space receive window given the @pswid.
+ *      - We must have a valid vasid and it must belong to this instance.
+ *        (so both send and receive windows are on the same VAS instance)
+ *      - The window must refer to an OPEN, FTW, RECEIVE window.
+ *
+ * NOTE: We access ->windows[] table and assume that vinst->mutex is held.
+ */
+static struct vas_window *get_user_rxwin(struct vas_instance *vinst, u32 pswid)
+{
+	int vasid, winid;
+	struct vas_window *rxwin;
+
+	decode_pswid(pswid, &vasid, &winid);
+
+	if (vinst->vas_id != vasid)
+		return ERR_PTR(-EINVAL);
+
+	rxwin = vinst->windows[winid];
+
+	if (!rxwin || rxwin->tx_win || rxwin->cop != VAS_COP_TYPE_FTW)
+		return ERR_PTR(-EINVAL);
+
+	return rxwin;
+}
+
+/*
  * Get the VAS receive window associated with NX engine identified
  * by @cop and if applicable, @pswid.
  *
@@ -581,10 +637,10 @@ static struct vas_window *get_vinst_rxwin(struct vas_instance *vinst,
 
 	mutex_lock(&vinst->mutex);
 
-	if (cop == VAS_COP_TYPE_842 || cop == VAS_COP_TYPE_842_HIPRI)
-		rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);
+	if (cop == VAS_COP_TYPE_FTW)
+		rxwin = get_user_rxwin(vinst, pswid);
 	else
-		rxwin = ERR_PTR(-EINVAL);
+		rxwin = vinst->rxwin[cop] ?: ERR_PTR(-EINVAL);
 
 	if (!IS_ERR(rxwin))
 		atomic_inc(&rxwin->num_txwins);
@@ -674,15 +730,18 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 
 	winctx->rx_fifo = rxattr->rx_fifo;
 	winctx->rx_fifo_size = rxattr->rx_fifo_size;
-	winctx->wcreds_max = rxattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+	winctx->wcreds_max = rxwin->wcreds_max;
 	winctx->pin_win = rxattr->pin_win;
 
 	winctx->nx_win = rxattr->nx_win;
 	winctx->fault_win = rxattr->fault_win;
+	winctx->user_win = rxattr->user_win;
+	winctx->rej_no_credit = rxattr->rej_no_credit;
 	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;
+	winctx->notify_early = rxattr->notify_early;
 
 	if (winctx->nx_win) {
 		winctx->data_stamp = true;
@@ -723,7 +782,10 @@ static void init_winctx_for_rxwin(struct vas_window *rxwin,
 static bool rx_win_args_valid(enum vas_cop_type cop,
 			struct vas_rx_win_attr *attr)
 {
-	dump_rx_win_attr(attr);
+	pr_debug("Rxattr: fault %d, notify %d, intr %d, early %d, fifo %d\n",
+			attr->fault_win, attr->notify_disable,
+			attr->intr_disable, attr->notify_early,
+			attr->rx_fifo_size);
 
 	if (cop >= VAS_COP_TYPE_MAX)
 		return false;
@@ -735,6 +797,9 @@ static bool rx_win_args_valid(enum vas_cop_type cop,
 	if (attr->rx_fifo_size > VAS_RX_FIFO_SIZE_MAX)
 		return false;
 
+	if (attr->wcreds_max > VAS_RX_WCREDS_MAX)
+		return false;
+
 	if (attr->nx_win) {
 		/* cannot be fault or user window if it is nx */
 		if (attr->fault_win || attr->user_win)
@@ -835,6 +900,7 @@ struct vas_window *vas_rx_win_open(int vasid, enum vas_cop_type cop,
 	rxwin->nx_win = rxattr->nx_win;
 	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);
 
@@ -884,21 +950,23 @@ static void init_winctx_for_txwin(struct vas_window *txwin,
 	 */
 	memset(winctx, 0, sizeof(struct vas_winctx));
 
-	winctx->wcreds_max = txattr->wcreds_max ?: VAS_WCREDS_DEFAULT;
+	winctx->wcreds_max = txwin->wcreds_max;
 
 	winctx->user_win = txattr->user_win;
 	winctx->nx_win = txwin->rxwin->nx_win;
 	winctx->pin_win = txattr->pin_win;
+	winctx->rej_no_credit = txattr->rej_no_credit;
+	winctx->rsvd_txbuf_enable = txattr->rsvd_txbuf_enable;
 
 	winctx->rx_wcred_mode = txattr->rx_wcred_mode;
 	winctx->tx_wcred_mode = txattr->tx_wcred_mode;
 	winctx->rx_word_mode = txattr->rx_win_ord_mode;
 	winctx->tx_word_mode = txattr->tx_win_ord_mode;
+	winctx->rsvd_txbuf_count = txattr->rsvd_txbuf_count;
 
-	if (winctx->nx_win) {
+	winctx->intr_disable = true;
+	if (winctx->nx_win)
 		winctx->data_stamp = true;
-		winctx->intr_disable = true;
-	}
 
 	winctx->lpid = txattr->lpid;
 	winctx->pidr = txattr->pidr;
@@ -921,6 +989,9 @@ static bool tx_win_args_valid(enum vas_cop_type cop,
 	if (cop > VAS_COP_TYPE_MAX)
 		return false;
 
+	if (attr->wcreds_max > VAS_TX_WCREDS_MAX)
+		return false;
+
 	if (attr->user_win &&
 			(cop != VAS_COP_TYPE_FTW || attr->rsvd_txbuf_count))
 		return false;
@@ -940,6 +1011,14 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
 	if (!tx_win_args_valid(cop, attr))
 		return ERR_PTR(-EINVAL);
 
+	/*
+	 * If caller did not specify a vasid but specified the PSWID of a
+	 * receive window (applicable only to FTW windows), use the vasid
+	 * from that receive window.
+	 */
+	if (vasid == -1 && attr->pswid)
+		decode_pswid(attr->pswid, &vasid, NULL);
+
 	vinst = find_vas_instance(vasid);
 	if (!vinst) {
 		pr_devel("vasid %d not found!\n", vasid);
@@ -958,11 +1037,13 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
 		goto put_rxwin;
 	}
 
+	txwin->cop = cop;
 	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;
 
 	init_winctx_for_txwin(txwin, attr, &winctx);
 
@@ -984,6 +1065,14 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
 		}
 	}
 
+	/*
+	 * Now that we have a send window, ensure context switch issues
+	 * CP_ABORT for this thread.
+	 */
+	rc = -EINVAL;
+	if (set_thread_uses_vas() < 0)
+		goto free_window;
+
 	set_vinst_win(vinst, txwin);
 
 	return txwin;
@@ -1038,50 +1127,110 @@ int vas_paste_crb(struct vas_window *txwin, int offset, bool re)
 	else
 		rc = -EINVAL;
 
-	print_fifo_msg_count(txwin);
+	pr_debug("Txwin #%d: Msg count %llu\n", txwin->winid,
+			read_hvwc_reg(txwin, VREG(LRFIFO_PUSH)));
 
 	return rc;
 }
 EXPORT_SYMBOL_GPL(vas_paste_crb);
 
+/*
+ * If credit checking is enabled for this window, poll for the return
+ * of window credits (i.e for NX engines to process any outstanding CRBs).
+ * Since NX-842 waits for the CRBs to be processed before closing the
+ * window, we should not have to wait for too long.
+ *
+ * TODO: We retry in 10ms intervals now. We could/should probably peek at
+ *	the VAS_LRFIFO_PUSH_OFFSET register to get an estimate of pending
+ *	CRBs on the FIFO and compute the delay dynamically on each retry.
+ *	But that is not really needed until we support NX-GZIP access from
+ *	user space. (NX-842 driver waits for CSB and Fast thread-wakeup
+ *	doesn't use credit checking).
+ */
+static void poll_window_credits(struct vas_window *window)
+{
+	u64 val;
+	int creds, mode;
+
+	val = read_hvwc_reg(window, VREG(WINCTL));
+	if (window->tx_win)
+		mode = GET_FIELD(VAS_WINCTL_TX_WCRED_MODE, val);
+	else
+		mode = GET_FIELD(VAS_WINCTL_RX_WCRED_MODE, val);
+
+	if (!mode)
+		return;
+retry:
+	if (window->tx_win) {
+		val = read_hvwc_reg(window, VREG(TX_WCRED));
+		creds = GET_FIELD(VAS_TX_WCRED, val);
+	} else {
+		val = read_hvwc_reg(window, VREG(LRX_WCRED));
+		creds = GET_FIELD(VAS_LRX_WCRED, val);
+	}
+
+	if (creds < window->wcreds_max) {
+		val = 0;
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(msecs_to_jiffies(10));
+		goto retry;
+	}
+}
+
+/*
+ * Wait for the window to go to "not-busy" state. It should only take a
+ * short time to queue a CRB, so window should not be busy for too long.
+ * Trying 5ms intervals.
+ */
 static void poll_window_busy_state(struct vas_window *window)
 {
 	int busy;
 	u64 val;
 
 retry:
-	/*
-	 * Poll Window Busy flag
-	 */
 	val = read_hvwc_reg(window, VREG(WIN_STATUS));
 	busy = GET_FIELD(VAS_WIN_BUSY, val);
 	if (busy) {
 		val = 0;
 		set_current_state(TASK_UNINTERRUPTIBLE);
-		schedule_timeout(HZ);
+		schedule_timeout(msecs_to_jiffies(5));
 		goto retry;
 	}
 }
 
+/*
+ * Have the hardware cast a window out of cache and wait for it to
+ * be completed.
+ *
+ * NOTE: It can take a relatively long time to cast the window context
+ *	out of the cache. It is not strictly necessary to cast out if:
+ *
+ *	- we clear the "Pin Window" bit (so hardware is free to evict)
+ *
+ *	- we re-initialize the window context when it is reassigned.
+ *
+ *	We do the former in vas_win_close() and latter in vas_win_open().
+ *	So, ignoring the cast-out for now. We can add it as needed. If
+ *	casting out becomes necessary we should consider offloading the
+ *	job to a worker thread, so the window close can proceed quickly.
+ */
 static void poll_window_castout(struct vas_window *window)
 {
-	int cached;
-	u64 val;
+	/* stub for now */
+}
 
-	/* Cast window context out of the cache */
-retry:
-	val = read_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL));
-	cached = GET_FIELD(VAS_WIN_CACHE_STATUS, val);
-	if (cached) {
-		val = 0ULL;
-		val = SET_FIELD(VAS_CASTOUT_REQ, val, 1);
-		val = SET_FIELD(VAS_PUSH_TO_MEM, val, 0);
-		write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), val);
+/*
+ * Unpin and close a window so no new requests are accepted and the
+ * hardware can evict this window from cache if necessary.
+ */
+static void unpin_close_window(struct vas_window *window)
+{
+	u64 val;
 
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		schedule_timeout(HZ);
-		goto retry;
-	}
+	val = read_hvwc_reg(window, VREG(WINCTL));
+	val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
+	val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
+	write_hvwc_reg(window, VREG(WINCTL), val);
 }
 
 /*
@@ -1098,8 +1247,6 @@ retry:
  */
 int vas_win_close(struct vas_window *window)
 {
-	u64 val;
-
 	if (!window)
 		return 0;
 
@@ -1115,11 +1262,9 @@ int vas_win_close(struct vas_window *window)
 
 	poll_window_busy_state(window);
 
-	/* Unpin window from cache and close it */
-	val = read_hvwc_reg(window, VREG(WINCTL));
-	val = SET_FIELD(VAS_WINCTL_PIN, val, 0);
-	val = SET_FIELD(VAS_WINCTL_OPEN, val, 0);
-	write_hvwc_reg(window, VREG(WINCTL), val);
+	unpin_close_window(window);
+
+	poll_window_credits(window);
 
 	poll_window_castout(window);
 
@@ -1132,3 +1277,12 @@ int vas_win_close(struct vas_window *window)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(vas_win_close);
+
+/*
+ * Return a system-wide unique window id for the window @win.
+ */
+u32 vas_win_id(struct vas_window *win)
+{
+	return encode_pswid(win->vinst->vas_id, win->winid);
+}
+EXPORT_SYMBOL_GPL(vas_win_id);