Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 446 insertions, 0 deletions

diff --git a/drivers/scsi/mac_esp.c b/drivers/scsi/mac_esp.c
new file mode 100644
index 000000000..a0ceaa242
--- /dev/null
+++ b/drivers/scsi/mac_esp.c
@@ -0,0 +1,446 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* mac_esp.c: ESP front-end for Macintosh Quadra systems.
+ *
+ * Adapted from jazz_esp.c and the old mac_esp.c.
+ *
+ * The pseudo DMA algorithm is based on the one used in NetBSD.
+ * See sys/arch/mac68k/obio/esp.c for some background information.
+ *
+ * Copyright (C) 2007-2008 Finn Thain
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/nubus.h>
+#include <linux/slab.h>
+
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <asm/macints.h>
+#include <asm/macintosh.h>
+#include <asm/mac_via.h>
+
+#include <scsi/scsi_host.h>
+
+#include "esp_scsi.h"
+
+#define DRV_MODULE_NAME     "mac_esp"
+#define PFX                 DRV_MODULE_NAME ": "
+#define DRV_VERSION         "1.000"
+#define DRV_MODULE_RELDATE  "Sept 15, 2007"
+
+#define MAC_ESP_IO_BASE          0x50F00000
+#define MAC_ESP_REGS_QUADRA      (MAC_ESP_IO_BASE + 0x10000)
+#define MAC_ESP_REGS_QUADRA2     (MAC_ESP_IO_BASE + 0xF000)
+#define MAC_ESP_REGS_QUADRA3     (MAC_ESP_IO_BASE + 0x18000)
+#define MAC_ESP_REGS_SPACING     0x402
+#define MAC_ESP_PDMA_REG         0xF9800024
+#define MAC_ESP_PDMA_REG_SPACING 0x4
+#define MAC_ESP_PDMA_IO_OFFSET   0x100
+
+#define esp_read8(REG)		mac_esp_read8(esp, REG)
+#define esp_write8(VAL, REG)	mac_esp_write8(esp, VAL, REG)
+
+struct mac_esp_priv {
+	struct esp *esp;
+	void __iomem *pdma_regs;
+	void __iomem *pdma_io;
+};
+static struct esp *esp_chips[2];
+static DEFINE_SPINLOCK(esp_chips_lock);
+
+#define MAC_ESP_GET_PRIV(esp) ((struct mac_esp_priv *) \
+			       dev_get_drvdata((esp)->dev))
+
+static inline void mac_esp_write8(struct esp *esp, u8 val, unsigned long reg)
+{
+	nubus_writeb(val, esp->regs + reg * 16);
+}
+
+static inline u8 mac_esp_read8(struct esp *esp, unsigned long reg)
+{
+	return nubus_readb(esp->regs + reg * 16);
+}
+
+static void mac_esp_reset_dma(struct esp *esp)
+{
+	/* Nothing to do. */
+}
+
+static void mac_esp_dma_drain(struct esp *esp)
+{
+	/* Nothing to do. */
+}
+
+static void mac_esp_dma_invalidate(struct esp *esp)
+{
+	/* Nothing to do. */
+}
+
+static int mac_esp_dma_error(struct esp *esp)
+{
+	return esp->send_cmd_error;
+}
+
+static inline int mac_esp_wait_for_empty_fifo(struct esp *esp)
+{
+	int i = 500000;
+
+	do {
+		if (!(esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES))
+			return 0;
+
+		if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
+			return 1;
+
+		udelay(2);
+	} while (--i);
+
+	printk(KERN_ERR PFX "FIFO is not empty (sreg %02x)\n",
+	       esp_read8(ESP_STATUS));
+	esp->send_cmd_error = 1;
+	return 1;
+}
+
+static inline int mac_esp_wait_for_dreq(struct esp *esp)
+{
+	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
+	int i = 500000;
+
+	do {
+		if (mep->pdma_regs == NULL) {
+			if (via2_scsi_drq_pending())
+				return 0;
+		} else {
+			if (nubus_readl(mep->pdma_regs) & 0x200)
+				return 0;
+		}
+
+		if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
+			return 1;
+
+		udelay(2);
+	} while (--i);
+
+	printk(KERN_ERR PFX "PDMA timeout (sreg %02x)\n",
+	       esp_read8(ESP_STATUS));
+	esp->send_cmd_error = 1;
+	return 1;
+}
+
+#define MAC_ESP_PDMA_LOOP(operands) \
+	asm volatile ( \
+	     "       tstw %1                   \n" \
+	     "       jbeq 20f                  \n" \
+	     "1:     movew " operands "        \n" \
+	     "2:     movew " operands "        \n" \
+	     "3:     movew " operands "        \n" \
+	     "4:     movew " operands "        \n" \
+	     "5:     movew " operands "        \n" \
+	     "6:     movew " operands "        \n" \
+	     "7:     movew " operands "        \n" \
+	     "8:     movew " operands "        \n" \
+	     "9:     movew " operands "        \n" \
+	     "10:    movew " operands "        \n" \
+	     "11:    movew " operands "        \n" \
+	     "12:    movew " operands "        \n" \
+	     "13:    movew " operands "        \n" \
+	     "14:    movew " operands "        \n" \
+	     "15:    movew " operands "        \n" \
+	     "16:    movew " operands "        \n" \
+	     "       subqw #1,%1               \n" \
+	     "       jbne 1b                   \n" \
+	     "20:    tstw %2                   \n" \
+	     "       jbeq 30f                  \n" \
+	     "21:    movew " operands "        \n" \
+	     "       subqw #1,%2               \n" \
+	     "       jbne 21b                  \n" \
+	     "30:    tstw %3                   \n" \
+	     "       jbeq 40f                  \n" \
+	     "31:    moveb " operands "        \n" \
+	     "32:    nop                       \n" \
+	     "40:                              \n" \
+	     "                                 \n" \
+	     "       .section __ex_table,\"a\" \n" \
+	     "       .align  4                 \n" \
+	     "       .long   1b,40b            \n" \
+	     "       .long   2b,40b            \n" \
+	     "       .long   3b,40b            \n" \
+	     "       .long   4b,40b            \n" \
+	     "       .long   5b,40b            \n" \
+	     "       .long   6b,40b            \n" \
+	     "       .long   7b,40b            \n" \
+	     "       .long   8b,40b            \n" \
+	     "       .long   9b,40b            \n" \
+	     "       .long  10b,40b            \n" \
+	     "       .long  11b,40b            \n" \
+	     "       .long  12b,40b            \n" \
+	     "       .long  13b,40b            \n" \
+	     "       .long  14b,40b            \n" \
+	     "       .long  15b,40b            \n" \
+	     "       .long  16b,40b            \n" \
+	     "       .long  21b,40b            \n" \
+	     "       .long  31b,40b            \n" \
+	     "       .long  32b,40b            \n" \
+	     "       .previous                 \n" \
+	     : "+a" (addr), "+r" (count32), "+r" (count2) \
+	     : "g" (count1), "a" (mep->pdma_io))
+
+static void mac_esp_send_pdma_cmd(struct esp *esp, u32 addr, u32 esp_count,
+				  u32 dma_count, int write, u8 cmd)
+{
+	struct mac_esp_priv *mep = MAC_ESP_GET_PRIV(esp);
+
+	esp->send_cmd_error = 0;
+
+	if (!write)
+		scsi_esp_cmd(esp, ESP_CMD_FLUSH);
+
+	esp_write8((esp_count >> 0) & 0xFF, ESP_TCLOW);
+	esp_write8((esp_count >> 8) & 0xFF, ESP_TCMED);
+
+	scsi_esp_cmd(esp, cmd);
+
+	do {
+		unsigned int count32 = esp_count >> 5;
+		unsigned int count2 = (esp_count & 0x1F) >> 1;
+		unsigned int count1 = esp_count & 1;
+		unsigned int start_addr = addr;
+
+		if (mac_esp_wait_for_dreq(esp))
+			break;
+
+		if (write) {
+			MAC_ESP_PDMA_LOOP("%4@,%0@+");
+
+			esp_count -= addr - start_addr;
+		} else {
+			unsigned int n;
+
+			MAC_ESP_PDMA_LOOP("%0@+,%4@");
+
+			if (mac_esp_wait_for_empty_fifo(esp))
+				break;
+
+			n = (esp_read8(ESP_TCMED) << 8) + esp_read8(ESP_TCLOW);
+			addr = start_addr + esp_count - n;
+			esp_count = n;
+		}
+	} while (esp_count);
+}
+
+static int mac_esp_irq_pending(struct esp *esp)
+{
+	if (esp_read8(ESP_STATUS) & ESP_STAT_INTR)
+		return 1;
+	return 0;
+}
+
+static u32 mac_esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
+{
+	return dma_len > 0xFFFF ? 0xFFFF : dma_len;
+}
+
+static irqreturn_t mac_scsi_esp_intr(int irq, void *dev_id)
+{
+	int got_intr;
+
+	/*
+	 * This is an edge triggered IRQ, so we have to be careful to
+	 * avoid missing a transition when it is shared by two ESP devices.
+	 */
+
+	do {
+		got_intr = 0;
+		if (esp_chips[0] &&
+		    (mac_esp_read8(esp_chips[0], ESP_STATUS) & ESP_STAT_INTR)) {
+			(void)scsi_esp_intr(irq, esp_chips[0]);
+			got_intr = 1;
+		}
+		if (esp_chips[1] &&
+		    (mac_esp_read8(esp_chips[1], ESP_STATUS) & ESP_STAT_INTR)) {
+			(void)scsi_esp_intr(irq, esp_chips[1]);
+			got_intr = 1;
+		}
+	} while (got_intr);
+
+	return IRQ_HANDLED;
+}
+
+static struct esp_driver_ops mac_esp_ops = {
+	.esp_write8       = mac_esp_write8,
+	.esp_read8        = mac_esp_read8,
+	.irq_pending      = mac_esp_irq_pending,
+	.dma_length_limit = mac_esp_dma_length_limit,
+	.reset_dma        = mac_esp_reset_dma,
+	.dma_drain        = mac_esp_dma_drain,
+	.dma_invalidate   = mac_esp_dma_invalidate,
+	.send_dma_cmd     = mac_esp_send_pdma_cmd,
+	.dma_error        = mac_esp_dma_error,
+};
+
+static int esp_mac_probe(struct platform_device *dev)
+{
+	const struct scsi_host_template *tpnt = &scsi_esp_template;
+	struct Scsi_Host *host;
+	struct esp *esp;
+	int err;
+	struct mac_esp_priv *mep;
+
+	if (!MACH_IS_MAC)
+		return -ENODEV;
+
+	if (dev->id > 1)
+		return -ENODEV;
+
+	host = scsi_host_alloc(tpnt, sizeof(struct esp));
+
+	err = -ENOMEM;
+	if (!host)
+		goto fail;
+
+	host->max_id = 8;
+	host->dma_boundary = PAGE_SIZE - 1;
+	esp = shost_priv(host);
+
+	esp->host = host;
+	esp->dev = &dev->dev;
+
+	esp->command_block = kzalloc(16, GFP_KERNEL);
+	if (!esp->command_block)
+		goto fail_unlink;
+	esp->command_block_dma = (dma_addr_t)esp->command_block;
+
+	esp->scsi_id = 7;
+	host->this_id = esp->scsi_id;
+	esp->scsi_id_mask = 1 << esp->scsi_id;
+
+	mep = kzalloc_obj(struct mac_esp_priv);
+	if (!mep)
+		goto fail_free_command_block;
+	mep->esp = esp;
+	platform_set_drvdata(dev, mep);
+
+	switch (macintosh_config->scsi_type) {
+	case MAC_SCSI_QUADRA:
+		esp->cfreq     = 16500000;
+		esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA;
+		mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
+		mep->pdma_regs = NULL;
+		break;
+	case MAC_SCSI_QUADRA2:
+		esp->cfreq     = 25000000;
+		esp->regs      = (void __iomem *)(MAC_ESP_REGS_QUADRA2 +
+				 dev->id * MAC_ESP_REGS_SPACING);
+		mep->pdma_io   = esp->regs + MAC_ESP_PDMA_IO_OFFSET;
+		mep->pdma_regs = (void __iomem *)(MAC_ESP_PDMA_REG +
+				 dev->id * MAC_ESP_PDMA_REG_SPACING);
+		nubus_writel(0x1d1, mep->pdma_regs);
+		break;
+	case MAC_SCSI_QUADRA3:
+		/* These quadras have a real DMA controller (the PSC) but we
+		 * don't know how to drive it so we must use PIO instead.
+		 */
+		esp->cfreq     = 25000000;
+		esp->regs      = (void __iomem *)MAC_ESP_REGS_QUADRA3;
+		mep->pdma_io   = NULL;
+		mep->pdma_regs = NULL;
+		break;
+	}
+	esp->fifo_reg = esp->regs + ESP_FDATA * 16;
+
+	esp->ops = &mac_esp_ops;
+	esp->flags = ESP_FLAG_NO_DMA_MAP;
+	if (mep->pdma_io == NULL) {
+		printk(KERN_INFO PFX "using PIO for controller %d\n", dev->id);
+		esp_write8(0, ESP_TCLOW);
+		esp_write8(0, ESP_TCMED);
+		esp->flags |= ESP_FLAG_DISABLE_SYNC;
+		mac_esp_ops.send_dma_cmd = esp_send_pio_cmd;
+	} else {
+		printk(KERN_INFO PFX "using PDMA for controller %d\n", dev->id);
+	}
+
+	host->irq = IRQ_MAC_SCSI;
+
+	/* The request_irq() call is intended to succeed for the first device
+	 * and fail for the second device.
+	 */
+	err = request_irq(host->irq, mac_scsi_esp_intr, 0, "ESP", NULL);
+	spin_lock(&esp_chips_lock);
+	if (err < 0 && esp_chips[!dev->id] == NULL) {
+		spin_unlock(&esp_chips_lock);
+		goto fail_free_priv;
+	}
+	esp_chips[dev->id] = esp;
+	spin_unlock(&esp_chips_lock);
+
+	err = scsi_esp_register(esp);
+	if (err)
+		goto fail_free_irq;
+
+	return 0;
+
+fail_free_irq:
+	spin_lock(&esp_chips_lock);
+	esp_chips[dev->id] = NULL;
+	if (esp_chips[!dev->id] == NULL) {
+		spin_unlock(&esp_chips_lock);
+		free_irq(host->irq, NULL);
+	} else
+		spin_unlock(&esp_chips_lock);
+fail_free_priv:
+	kfree(mep);
+fail_free_command_block:
+	kfree(esp->command_block);
+fail_unlink:
+	scsi_host_put(host);
+fail:
+	return err;
+}
+
+static void esp_mac_remove(struct platform_device *dev)
+{
+	struct mac_esp_priv *mep = platform_get_drvdata(dev);
+	struct esp *esp = mep->esp;
+	unsigned int irq = esp->host->irq;
+
+	scsi_esp_unregister(esp);
+
+	spin_lock(&esp_chips_lock);
+	esp_chips[dev->id] = NULL;
+	if (esp_chips[!dev->id] == NULL) {
+		spin_unlock(&esp_chips_lock);
+		free_irq(irq, NULL);
+	} else
+		spin_unlock(&esp_chips_lock);
+
+	kfree(mep);
+
+	kfree(esp->command_block);
+
+	scsi_host_put(esp->host);
+}
+
+static struct platform_driver esp_mac_driver = {
+	.probe    = esp_mac_probe,
+	.remove   = esp_mac_remove,
+	.driver   = {
+		.name	= DRV_MODULE_NAME,
+	},
+};
+module_platform_driver(esp_mac_driver);
+
+MODULE_DESCRIPTION("Mac ESP SCSI driver");
+MODULE_AUTHOR("Finn Thain");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(DRV_VERSION);
+MODULE_ALIAS("platform:" DRV_MODULE_NAME);