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, 415 insertions, 0 deletions

diff --git a/drivers/fpga/microchip-spi.c b/drivers/fpga/microchip-spi.c
new file mode 100644
index 000000000..cc8f6d7bb
--- /dev/null
+++ b/drivers/fpga/microchip-spi.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip Polarfire FPGA programming over slave SPI interface.
+ */
+
+#include <linux/unaligned.h>
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+#define	MPF_SPI_ISC_ENABLE	0x0B
+#define	MPF_SPI_ISC_DISABLE	0x0C
+#define	MPF_SPI_READ_STATUS	0x00
+#define	MPF_SPI_READ_DATA	0x01
+#define	MPF_SPI_FRAME_INIT	0xAE
+#define	MPF_SPI_FRAME		0xEE
+#define	MPF_SPI_PRG_MODE	0x01
+#define	MPF_SPI_RELEASE		0x23
+
+#define	MPF_SPI_FRAME_SIZE	16
+
+#define	MPF_HEADER_SIZE_OFFSET	24
+#define	MPF_DATA_SIZE_OFFSET	55
+
+#define	MPF_LOOKUP_TABLE_RECORD_SIZE		9
+#define	MPF_LOOKUP_TABLE_BLOCK_ID_OFFSET	0
+#define	MPF_LOOKUP_TABLE_BLOCK_START_OFFSET	1
+
+#define	MPF_COMPONENTS_SIZE_ID	5
+#define	MPF_BITSTREAM_ID	8
+
+#define	MPF_BITS_PER_COMPONENT_SIZE	22
+
+#define	MPF_STATUS_POLL_TIMEOUT		(2 * USEC_PER_SEC)
+#define	MPF_STATUS_BUSY			BIT(0)
+#define	MPF_STATUS_READY		BIT(1)
+#define	MPF_STATUS_SPI_VIOLATION	BIT(2)
+#define	MPF_STATUS_SPI_ERROR		BIT(3)
+
+struct mpf_priv {
+	struct spi_device *spi;
+	bool program_mode;
+	u8 tx __aligned(ARCH_KMALLOC_MINALIGN);
+	u8 rx;
+};
+
+static int mpf_read_status(struct mpf_priv *priv)
+{
+	/*
+	 * HW status is returned on MISO in the first byte after CS went
+	 * active. However, first reading can be inadequate, so we submit
+	 * two identical SPI transfers and use result of the later one.
+	 */
+	struct spi_transfer xfers[2] = {
+		{
+			.tx_buf = &priv->tx,
+			.rx_buf = &priv->rx,
+			.len = 1,
+			.cs_change = 1,
+		}, {
+			.tx_buf = &priv->tx,
+			.rx_buf = &priv->rx,
+			.len = 1,
+		},
+	};
+	u8 status;
+	int ret;
+
+	priv->tx = MPF_SPI_READ_STATUS;
+
+	ret = spi_sync_transfer(priv->spi, xfers, 2);
+	if (ret)
+		return ret;
+
+	status = priv->rx;
+
+	if ((status & MPF_STATUS_SPI_VIOLATION) ||
+	    (status & MPF_STATUS_SPI_ERROR))
+		return -EIO;
+
+	return status;
+}
+
+static enum fpga_mgr_states mpf_ops_state(struct fpga_manager *mgr)
+{
+	struct mpf_priv *priv = mgr->priv;
+	bool program_mode;
+	int status;
+
+	program_mode = priv->program_mode;
+	status = mpf_read_status(priv);
+
+	if (!program_mode && !status)
+		return FPGA_MGR_STATE_OPERATING;
+
+	return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int mpf_ops_parse_header(struct fpga_manager *mgr,
+				struct fpga_image_info *info,
+				const char *buf, size_t count)
+{
+	size_t component_size_byte_num, component_size_byte_off,
+	       components_size_start, bitstream_start,
+	       block_id_offset, block_start_offset;
+	u8 header_size, blocks_num, block_id;
+	u32 block_start, component_size;
+	u16 components_num, i;
+
+	if (!buf) {
+		dev_err(&mgr->dev, "Image buffer is not provided\n");
+		return -EINVAL;
+	}
+
+	header_size = *(buf + MPF_HEADER_SIZE_OFFSET);
+	if (!header_size)
+		return -EINVAL;
+
+	if (header_size > count) {
+		info->header_size = header_size;
+		return -EAGAIN;
+	}
+
+	/*
+	 * Go through look-up table to find out where actual bitstream starts
+	 * and where sizes of components of the bitstream lies.
+	 */
+	blocks_num = *(buf + header_size - 1);
+	block_id_offset = header_size + MPF_LOOKUP_TABLE_BLOCK_ID_OFFSET;
+	block_start_offset = header_size + MPF_LOOKUP_TABLE_BLOCK_START_OFFSET;
+
+	header_size += blocks_num * MPF_LOOKUP_TABLE_RECORD_SIZE;
+	if (header_size > count) {
+		info->header_size = header_size;
+		return -EAGAIN;
+	}
+
+	components_size_start = 0;
+	bitstream_start = 0;
+
+	while (blocks_num--) {
+		block_id = *(buf + block_id_offset);
+		block_start = get_unaligned_le32(buf + block_start_offset);
+
+		switch (block_id) {
+		case MPF_BITSTREAM_ID:
+			bitstream_start = block_start;
+			info->header_size = block_start;
+			if (block_start > count)
+				return -EAGAIN;
+
+			break;
+		case MPF_COMPONENTS_SIZE_ID:
+			components_size_start = block_start;
+			break;
+		default:
+			break;
+		}
+
+		if (bitstream_start && components_size_start)
+			break;
+
+		block_id_offset += MPF_LOOKUP_TABLE_RECORD_SIZE;
+		block_start_offset += MPF_LOOKUP_TABLE_RECORD_SIZE;
+	}
+
+	if (!bitstream_start || !components_size_start) {
+		dev_err(&mgr->dev, "Failed to parse header look-up table\n");
+		return -EFAULT;
+	}
+
+	/*
+	 * Parse bitstream size.
+	 * Sizes of components of the bitstream are 22-bits long placed next
+	 * to each other. Image header should be extended by now up to where
+	 * actual bitstream starts, so no need for overflow check anymore.
+	 */
+	components_num = get_unaligned_le16(buf + MPF_DATA_SIZE_OFFSET);
+
+	for (i = 0; i < components_num; i++) {
+		component_size_byte_num =
+			(i * MPF_BITS_PER_COMPONENT_SIZE) / BITS_PER_BYTE;
+		component_size_byte_off =
+			(i * MPF_BITS_PER_COMPONENT_SIZE) % BITS_PER_BYTE;
+
+		component_size = get_unaligned_le32(buf +
+						    components_size_start +
+						    component_size_byte_num);
+		component_size >>= component_size_byte_off;
+		component_size &= GENMASK(MPF_BITS_PER_COMPONENT_SIZE - 1, 0);
+
+		info->data_size += component_size * MPF_SPI_FRAME_SIZE;
+	}
+
+	return 0;
+}
+
+static int mpf_poll_status(struct mpf_priv *priv, u8 mask)
+{
+	int ret, status;
+
+	/*
+	 * Busy poll HW status. Polling stops if any of the following
+	 * conditions are met:
+	 *  - timeout is reached
+	 *  - mpf_read_status() returns an error
+	 *  - busy bit is cleared AND mask bits are set
+	 */
+	ret = read_poll_timeout(mpf_read_status, status,
+				(status < 0) ||
+				((status & (MPF_STATUS_BUSY | mask)) == mask),
+				0, MPF_STATUS_POLL_TIMEOUT, false, priv);
+	if (ret < 0)
+		return ret;
+
+	return status;
+}
+
+static int mpf_spi_write(struct mpf_priv *priv, const void *buf, size_t buf_size)
+{
+	int status = mpf_poll_status(priv, 0);
+
+	if (status < 0)
+		return status;
+
+	return spi_write_then_read(priv->spi, buf, buf_size, NULL, 0);
+}
+
+static int mpf_spi_write_then_read(struct mpf_priv *priv,
+				   const void *txbuf, size_t txbuf_size,
+				   void *rxbuf, size_t rxbuf_size)
+{
+	const u8 read_command[] = { MPF_SPI_READ_DATA };
+	int ret;
+
+	ret = mpf_spi_write(priv, txbuf, txbuf_size);
+	if (ret)
+		return ret;
+
+	ret = mpf_poll_status(priv, MPF_STATUS_READY);
+	if (ret < 0)
+		return ret;
+
+	return spi_write_then_read(priv->spi, read_command, sizeof(read_command),
+				   rxbuf, rxbuf_size);
+}
+
+static int mpf_ops_write_init(struct fpga_manager *mgr,
+			      struct fpga_image_info *info, const char *buf,
+			      size_t count)
+{
+	const u8 program_mode[] = { MPF_SPI_FRAME_INIT, MPF_SPI_PRG_MODE };
+	const u8 isc_en_command[] = { MPF_SPI_ISC_ENABLE };
+	struct mpf_priv *priv = mgr->priv;
+	struct device *dev = &mgr->dev;
+	u32 isc_ret = 0;
+	int ret;
+
+	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
+		dev_err(dev, "Partial reconfiguration is not supported\n");
+		return -EOPNOTSUPP;
+	}
+
+	ret = mpf_spi_write_then_read(priv, isc_en_command, sizeof(isc_en_command),
+				      &isc_ret, sizeof(isc_ret));
+	if (ret || isc_ret) {
+		dev_err(dev, "Failed to enable ISC: spi_ret %d, isc_ret %u\n",
+			ret, isc_ret);
+		return -EFAULT;
+	}
+
+	ret = mpf_spi_write(priv, program_mode, sizeof(program_mode));
+	if (ret) {
+		dev_err(dev, "Failed to enter program mode: %d\n", ret);
+		return ret;
+	}
+
+	priv->program_mode = true;
+
+	return 0;
+}
+
+static int mpf_spi_frame_write(struct mpf_priv *priv, const char *buf)
+{
+	struct spi_transfer xfers[2] = {
+		{
+			.tx_buf = &priv->tx,
+			.len = 1,
+		}, {
+			.tx_buf = buf,
+			.len = MPF_SPI_FRAME_SIZE,
+		},
+	};
+	int ret;
+
+	ret = mpf_poll_status(priv, 0);
+	if (ret < 0)
+		return ret;
+
+	priv->tx = MPF_SPI_FRAME;
+
+	return spi_sync_transfer(priv->spi, xfers, ARRAY_SIZE(xfers));
+}
+
+static int mpf_ops_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+	struct mpf_priv *priv = mgr->priv;
+	struct device *dev = &mgr->dev;
+	int ret, i;
+
+	if (count % MPF_SPI_FRAME_SIZE) {
+		dev_err(dev, "Bitstream size is not a multiple of %d\n",
+			MPF_SPI_FRAME_SIZE);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < count / MPF_SPI_FRAME_SIZE; i++) {
+		ret = mpf_spi_frame_write(priv, buf + i * MPF_SPI_FRAME_SIZE);
+		if (ret) {
+			dev_err(dev, "Failed to write bitstream frame %d/%zu\n",
+				i, count / MPF_SPI_FRAME_SIZE);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int mpf_ops_write_complete(struct fpga_manager *mgr,
+				  struct fpga_image_info *info)
+{
+	const u8 isc_dis_command[] = { MPF_SPI_ISC_DISABLE };
+	const u8 release_command[] = { MPF_SPI_RELEASE };
+	struct mpf_priv *priv = mgr->priv;
+	struct device *dev = &mgr->dev;
+	int ret;
+
+	ret = mpf_spi_write(priv, isc_dis_command, sizeof(isc_dis_command));
+	if (ret) {
+		dev_err(dev, "Failed to disable ISC: %d\n", ret);
+		return ret;
+	}
+
+	usleep_range(1000, 2000);
+
+	ret = mpf_spi_write(priv, release_command, sizeof(release_command));
+	if (ret) {
+		dev_err(dev, "Failed to exit program mode: %d\n", ret);
+		return ret;
+	}
+
+	priv->program_mode = false;
+
+	return 0;
+}
+
+static const struct fpga_manager_ops mpf_ops = {
+	.state = mpf_ops_state,
+	.initial_header_size = 71,
+	.skip_header = true,
+	.parse_header = mpf_ops_parse_header,
+	.write_init = mpf_ops_write_init,
+	.write = mpf_ops_write,
+	.write_complete = mpf_ops_write_complete,
+};
+
+static int mpf_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct fpga_manager *mgr;
+	struct mpf_priv *priv;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->spi = spi;
+
+	mgr = devm_fpga_mgr_register(dev, "Microchip Polarfire SPI FPGA Manager",
+				     &mpf_ops, priv);
+
+	return PTR_ERR_OR_ZERO(mgr);
+}
+
+static const struct spi_device_id mpf_spi_ids[] = {
+	{ .name = "mpf-spi-fpga-mgr", },
+	{},
+};
+MODULE_DEVICE_TABLE(spi, mpf_spi_ids);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id mpf_of_ids[] = {
+	{ .compatible = "microchip,mpf-spi-fpga-mgr" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpf_of_ids);
+#endif /* IS_ENABLED(CONFIG_OF) */
+
+static struct spi_driver mpf_driver = {
+	.probe = mpf_probe,
+	.id_table = mpf_spi_ids,
+	.driver = {
+		.name = "microchip_mpf_spi_fpga_mgr",
+		.of_match_table = of_match_ptr(mpf_of_ids),
+	},
+};
+
+module_spi_driver(mpf_driver);
+
+MODULE_DESCRIPTION("Microchip Polarfire SPI FPGA Manager");
+MODULE_AUTHOR("Ivan Bornyakov <i.bornyakov@metrotek.ru>");
+MODULE_LICENSE("GPL");