Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 851 insertions, 0 deletions

diff --git a/drivers/block/ps3vram.c b/drivers/block/ps3vram.c
new file mode 100644
index 000000000..41cc8cefe
--- /dev/null
+++ b/drivers/block/ps3vram.c
@@ -0,0 +1,851 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ps3vram - Use extra PS3 video ram as block device.
+ *
+ * Copyright 2009 Sony Corporation
+ *
+ * Based on the MTD ps3vram driver, which is
+ * Copyright (c) 2007-2008 Jim Paris <jim@jtan.com>
+ * Added support RSX DMA Vivien Chappelier <vivien.chappelier@free.fr>
+ */
+
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+
+#include <asm/cell-regs.h>
+#include <asm/firmware.h>
+#include <asm/lv1call.h>
+#include <asm/ps3.h>
+#include <asm/ps3gpu.h>
+
+
+#define DEVICE_NAME		"ps3vram"
+
+
+#define XDR_BUF_SIZE (2 * 1024 * 1024) /* XDR buffer (must be 1MiB aligned) */
+#define XDR_IOIF 0x0c000000
+
+#define FIFO_BASE XDR_IOIF
+#define FIFO_SIZE (64 * 1024)
+
+#define DMA_PAGE_SIZE (4 * 1024)
+
+#define CACHE_PAGE_SIZE (256 * 1024)
+#define CACHE_PAGE_COUNT ((XDR_BUF_SIZE - FIFO_SIZE) / CACHE_PAGE_SIZE)
+
+#define CACHE_OFFSET CACHE_PAGE_SIZE
+#define FIFO_OFFSET 0
+
+#define CTRL_PUT 0x10
+#define CTRL_GET 0x11
+#define CTRL_TOP 0x15
+
+#define UPLOAD_SUBCH	1
+#define DOWNLOAD_SUBCH	2
+
+#define NV_MEMORY_TO_MEMORY_FORMAT_OFFSET_IN	0x0000030c
+#define NV_MEMORY_TO_MEMORY_FORMAT_NOTIFY	0x00000104
+
+#define CACHE_PAGE_PRESENT 1
+#define CACHE_PAGE_DIRTY   2
+
+struct ps3vram_tag {
+	unsigned int address;
+	unsigned int flags;
+};
+
+struct ps3vram_cache {
+	unsigned int page_count;
+	unsigned int page_size;
+	struct ps3vram_tag *tags;
+	unsigned int hit;
+	unsigned int miss;
+};
+
+struct ps3vram_priv {
+	struct gendisk *gendisk;
+
+	u64 size;
+
+	u64 memory_handle;
+	u64 context_handle;
+	u32 __iomem *ctrl;
+	void __iomem *reports;
+	u8 *xdr_buf;
+
+	u32 *fifo_base;
+	u32 *fifo_ptr;
+
+	struct ps3vram_cache cache;
+
+	spinlock_t lock;	/* protecting list of bios */
+	struct bio_list list;
+};
+
+
+static int ps3vram_major;
+
+#define DMA_NOTIFIER_HANDLE_BASE 0x66604200 /* first DMA notifier handle */
+#define DMA_NOTIFIER_OFFSET_BASE 0x1000     /* first DMA notifier offset */
+#define DMA_NOTIFIER_SIZE        0x40
+#define NOTIFIER 7	/* notifier used for completion report */
+
+static char *size = "256M";
+module_param(size, charp, 0);
+MODULE_PARM_DESC(size, "memory size");
+
+static u32 __iomem *ps3vram_get_notifier(void __iomem *reports, int notifier)
+{
+	return reports + DMA_NOTIFIER_OFFSET_BASE +
+	       DMA_NOTIFIER_SIZE * notifier;
+}
+
+static void ps3vram_notifier_reset(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	u32 __iomem *notify = ps3vram_get_notifier(priv->reports, NOTIFIER);
+	int i;
+
+	for (i = 0; i < 4; i++)
+		iowrite32be(0xffffffff, notify + i);
+}
+
+static int ps3vram_notifier_wait(struct ps3_system_bus_device *dev,
+				 unsigned int timeout_ms)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	u32 __iomem *notify = ps3vram_get_notifier(priv->reports, NOTIFIER);
+	unsigned long timeout;
+
+	for (timeout = 20; timeout; timeout--) {
+		if (!ioread32be(notify + 3))
+			return 0;
+		udelay(10);
+	}
+
+	timeout = jiffies + msecs_to_jiffies(timeout_ms);
+
+	do {
+		if (!ioread32be(notify + 3))
+			return 0;
+		msleep(1);
+	} while (time_before(jiffies, timeout));
+
+	return -ETIMEDOUT;
+}
+
+static void ps3vram_init_ring(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	iowrite32be(FIFO_BASE + FIFO_OFFSET, priv->ctrl + CTRL_PUT);
+	iowrite32be(FIFO_BASE + FIFO_OFFSET, priv->ctrl + CTRL_GET);
+}
+
+static int ps3vram_wait_ring(struct ps3_system_bus_device *dev,
+			     unsigned int timeout_ms)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);
+
+	do {
+		if (ioread32be(priv->ctrl + CTRL_PUT) == ioread32be(priv->ctrl + CTRL_GET))
+			return 0;
+		msleep(1);
+	} while (time_before(jiffies, timeout));
+
+	dev_warn(&dev->core, "FIFO timeout (%08x/%08x/%08x)\n",
+		 ioread32be(priv->ctrl + CTRL_PUT), ioread32be(priv->ctrl + CTRL_GET),
+		 ioread32be(priv->ctrl + CTRL_TOP));
+
+	return -ETIMEDOUT;
+}
+
+static void ps3vram_out_ring(struct ps3vram_priv *priv, u32 data)
+{
+	*(priv->fifo_ptr)++ = data;
+}
+
+static void ps3vram_begin_ring(struct ps3vram_priv *priv, u32 chan, u32 tag,
+			       u32 size)
+{
+	ps3vram_out_ring(priv, (size << 18) | (chan << 13) | tag);
+}
+
+static void ps3vram_rewind_ring(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	int status;
+
+	ps3vram_out_ring(priv, 0x20000000 | (FIFO_BASE + FIFO_OFFSET));
+
+	iowrite32be(FIFO_BASE + FIFO_OFFSET, priv->ctrl + CTRL_PUT);
+
+	/* asking the HV for a blit will kick the FIFO */
+	status = lv1_gpu_fb_blit(priv->context_handle, 0, 0, 0, 0);
+	if (status)
+		dev_err(&dev->core, "%s: lv1_gpu_fb_blit failed %d\n",
+			__func__, status);
+
+	priv->fifo_ptr = priv->fifo_base;
+}
+
+static void ps3vram_fire_ring(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	int status;
+
+	mutex_lock(&ps3_gpu_mutex);
+
+	iowrite32be(FIFO_BASE + FIFO_OFFSET + (priv->fifo_ptr - priv->fifo_base)
+		* sizeof(u32), priv->ctrl + CTRL_PUT);
+
+	/* asking the HV for a blit will kick the FIFO */
+	status = lv1_gpu_fb_blit(priv->context_handle, 0, 0, 0, 0);
+	if (status)
+		dev_err(&dev->core, "%s: lv1_gpu_fb_blit failed %d\n",
+			__func__, status);
+
+	if ((priv->fifo_ptr - priv->fifo_base) * sizeof(u32) >
+	    FIFO_SIZE - 1024) {
+		dev_dbg(&dev->core, "FIFO full, rewinding\n");
+		ps3vram_wait_ring(dev, 200);
+		ps3vram_rewind_ring(dev);
+	}
+
+	mutex_unlock(&ps3_gpu_mutex);
+}
+
+static void ps3vram_bind(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	ps3vram_begin_ring(priv, UPLOAD_SUBCH, 0, 1);
+	ps3vram_out_ring(priv, 0x31337303);
+	ps3vram_begin_ring(priv, UPLOAD_SUBCH, 0x180, 3);
+	ps3vram_out_ring(priv, DMA_NOTIFIER_HANDLE_BASE + NOTIFIER);
+	ps3vram_out_ring(priv, 0xfeed0001);	/* DMA system RAM instance */
+	ps3vram_out_ring(priv, 0xfeed0000);     /* DMA video RAM instance */
+
+	ps3vram_begin_ring(priv, DOWNLOAD_SUBCH, 0, 1);
+	ps3vram_out_ring(priv, 0x3137c0de);
+	ps3vram_begin_ring(priv, DOWNLOAD_SUBCH, 0x180, 3);
+	ps3vram_out_ring(priv, DMA_NOTIFIER_HANDLE_BASE + NOTIFIER);
+	ps3vram_out_ring(priv, 0xfeed0000);	/* DMA video RAM instance */
+	ps3vram_out_ring(priv, 0xfeed0001);	/* DMA system RAM instance */
+
+	ps3vram_fire_ring(dev);
+}
+
+static int ps3vram_upload(struct ps3_system_bus_device *dev,
+			  unsigned int src_offset, unsigned int dst_offset,
+			  int len, int count)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	ps3vram_begin_ring(priv, UPLOAD_SUBCH,
+			   NV_MEMORY_TO_MEMORY_FORMAT_OFFSET_IN, 8);
+	ps3vram_out_ring(priv, XDR_IOIF + src_offset);
+	ps3vram_out_ring(priv, dst_offset);
+	ps3vram_out_ring(priv, len);
+	ps3vram_out_ring(priv, len);
+	ps3vram_out_ring(priv, len);
+	ps3vram_out_ring(priv, count);
+	ps3vram_out_ring(priv, (1 << 8) | 1);
+	ps3vram_out_ring(priv, 0);
+
+	ps3vram_notifier_reset(dev);
+	ps3vram_begin_ring(priv, UPLOAD_SUBCH,
+			   NV_MEMORY_TO_MEMORY_FORMAT_NOTIFY, 1);
+	ps3vram_out_ring(priv, 0);
+	ps3vram_begin_ring(priv, UPLOAD_SUBCH, 0x100, 1);
+	ps3vram_out_ring(priv, 0);
+	ps3vram_fire_ring(dev);
+	if (ps3vram_notifier_wait(dev, 200) < 0) {
+		dev_warn(&dev->core, "%s: Notifier timeout\n", __func__);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int ps3vram_download(struct ps3_system_bus_device *dev,
+			    unsigned int src_offset, unsigned int dst_offset,
+			    int len, int count)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	ps3vram_begin_ring(priv, DOWNLOAD_SUBCH,
+			   NV_MEMORY_TO_MEMORY_FORMAT_OFFSET_IN, 8);
+	ps3vram_out_ring(priv, src_offset);
+	ps3vram_out_ring(priv, XDR_IOIF + dst_offset);
+	ps3vram_out_ring(priv, len);
+	ps3vram_out_ring(priv, len);
+	ps3vram_out_ring(priv, len);
+	ps3vram_out_ring(priv, count);
+	ps3vram_out_ring(priv, (1 << 8) | 1);
+	ps3vram_out_ring(priv, 0);
+
+	ps3vram_notifier_reset(dev);
+	ps3vram_begin_ring(priv, DOWNLOAD_SUBCH,
+			   NV_MEMORY_TO_MEMORY_FORMAT_NOTIFY, 1);
+	ps3vram_out_ring(priv, 0);
+	ps3vram_begin_ring(priv, DOWNLOAD_SUBCH, 0x100, 1);
+	ps3vram_out_ring(priv, 0);
+	ps3vram_fire_ring(dev);
+	if (ps3vram_notifier_wait(dev, 200) < 0) {
+		dev_warn(&dev->core, "%s: Notifier timeout\n", __func__);
+		return -1;
+	}
+
+	return 0;
+}
+
+static void ps3vram_cache_evict(struct ps3_system_bus_device *dev, int entry)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	struct ps3vram_cache *cache = &priv->cache;
+
+	if (!(cache->tags[entry].flags & CACHE_PAGE_DIRTY))
+		return;
+
+	dev_dbg(&dev->core, "Flushing %d: 0x%08x\n", entry,
+		cache->tags[entry].address);
+	if (ps3vram_upload(dev, CACHE_OFFSET + entry * cache->page_size,
+			   cache->tags[entry].address, DMA_PAGE_SIZE,
+			   cache->page_size / DMA_PAGE_SIZE) < 0) {
+		dev_err(&dev->core,
+			"Failed to upload from 0x%x to " "0x%x size 0x%x\n",
+			entry * cache->page_size, cache->tags[entry].address,
+			cache->page_size);
+	}
+	cache->tags[entry].flags &= ~CACHE_PAGE_DIRTY;
+}
+
+static void ps3vram_cache_load(struct ps3_system_bus_device *dev, int entry,
+			       unsigned int address)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	struct ps3vram_cache *cache = &priv->cache;
+
+	dev_dbg(&dev->core, "Fetching %d: 0x%08x\n", entry, address);
+	if (ps3vram_download(dev, address,
+			     CACHE_OFFSET + entry * cache->page_size,
+			     DMA_PAGE_SIZE,
+			     cache->page_size / DMA_PAGE_SIZE) < 0) {
+		dev_err(&dev->core,
+			"Failed to download from 0x%x to 0x%x size 0x%x\n",
+			address, entry * cache->page_size, cache->page_size);
+	}
+
+	cache->tags[entry].address = address;
+	cache->tags[entry].flags |= CACHE_PAGE_PRESENT;
+}
+
+
+static void ps3vram_cache_flush(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	struct ps3vram_cache *cache = &priv->cache;
+	int i;
+
+	dev_dbg(&dev->core, "FLUSH\n");
+	for (i = 0; i < cache->page_count; i++) {
+		ps3vram_cache_evict(dev, i);
+		cache->tags[i].flags = 0;
+	}
+}
+
+static unsigned int ps3vram_cache_match(struct ps3_system_bus_device *dev,
+					loff_t address)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	struct ps3vram_cache *cache = &priv->cache;
+	unsigned int base;
+	unsigned int offset;
+	int i;
+	static int counter;
+
+	offset = (unsigned int) (address & (cache->page_size - 1));
+	base = (unsigned int) (address - offset);
+
+	/* fully associative check */
+	for (i = 0; i < cache->page_count; i++) {
+		if ((cache->tags[i].flags & CACHE_PAGE_PRESENT) &&
+		    cache->tags[i].address == base) {
+			cache->hit++;
+			dev_dbg(&dev->core, "Found entry %d: 0x%08x\n", i,
+				cache->tags[i].address);
+			return i;
+		}
+	}
+
+	/* choose a random entry */
+	i = (jiffies + (counter++)) % cache->page_count;
+	dev_dbg(&dev->core, "Using entry %d\n", i);
+
+	ps3vram_cache_evict(dev, i);
+	ps3vram_cache_load(dev, i, base);
+
+	cache->miss++;
+	return i;
+}
+
+static int ps3vram_cache_init(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	priv->cache.page_count = CACHE_PAGE_COUNT;
+	priv->cache.page_size = CACHE_PAGE_SIZE;
+	priv->cache.tags = kzalloc_objs(struct ps3vram_tag, CACHE_PAGE_COUNT);
+	if (!priv->cache.tags)
+		return -ENOMEM;
+
+	dev_info(&dev->core, "Created ram cache: %d entries, %d KiB each\n",
+		CACHE_PAGE_COUNT, CACHE_PAGE_SIZE / 1024);
+
+	return 0;
+}
+
+static void ps3vram_cache_cleanup(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	ps3vram_cache_flush(dev);
+	kfree(priv->cache.tags);
+}
+
+static blk_status_t ps3vram_read(struct ps3_system_bus_device *dev, loff_t from,
+			size_t len, size_t *retlen, u_char *buf)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	unsigned int cached, count;
+
+	dev_dbg(&dev->core, "%s: from=0x%08x len=0x%zx\n", __func__,
+		(unsigned int)from, len);
+
+	if (from >= priv->size)
+		return BLK_STS_IOERR;
+
+	if (len > priv->size - from)
+		len = priv->size - from;
+
+	/* Copy from vram to buf */
+	count = len;
+	while (count) {
+		unsigned int offset, avail;
+		unsigned int entry;
+
+		offset = (unsigned int) (from & (priv->cache.page_size - 1));
+		avail  = priv->cache.page_size - offset;
+
+		entry = ps3vram_cache_match(dev, from);
+		cached = CACHE_OFFSET + entry * priv->cache.page_size + offset;
+
+		dev_dbg(&dev->core, "%s: from=%08x cached=%08x offset=%08x "
+			"avail=%08x count=%08x\n", __func__,
+			(unsigned int)from, cached, offset, avail, count);
+
+		if (avail > count)
+			avail = count;
+		memcpy(buf, priv->xdr_buf + cached, avail);
+
+		buf += avail;
+		count -= avail;
+		from += avail;
+	}
+
+	*retlen = len;
+	return 0;
+}
+
+static blk_status_t ps3vram_write(struct ps3_system_bus_device *dev, loff_t to,
+			 size_t len, size_t *retlen, const u_char *buf)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	unsigned int cached, count;
+
+	if (to >= priv->size)
+		return BLK_STS_IOERR;
+
+	if (len > priv->size - to)
+		len = priv->size - to;
+
+	/* Copy from buf to vram */
+	count = len;
+	while (count) {
+		unsigned int offset, avail;
+		unsigned int entry;
+
+		offset = (unsigned int) (to & (priv->cache.page_size - 1));
+		avail  = priv->cache.page_size - offset;
+
+		entry = ps3vram_cache_match(dev, to);
+		cached = CACHE_OFFSET + entry * priv->cache.page_size + offset;
+
+		dev_dbg(&dev->core, "%s: to=%08x cached=%08x offset=%08x "
+			"avail=%08x count=%08x\n", __func__, (unsigned int)to,
+			cached, offset, avail, count);
+
+		if (avail > count)
+			avail = count;
+		memcpy(priv->xdr_buf + cached, buf, avail);
+
+		priv->cache.tags[entry].flags |= CACHE_PAGE_DIRTY;
+
+		buf += avail;
+		count -= avail;
+		to += avail;
+	}
+
+	*retlen = len;
+	return 0;
+}
+
+static int ps3vram_proc_show(struct seq_file *m, void *v)
+{
+	struct ps3vram_priv *priv = m->private;
+
+	seq_printf(m, "hit:%u\nmiss:%u\n", priv->cache.hit, priv->cache.miss);
+	return 0;
+}
+
+static void ps3vram_proc_init(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	struct proc_dir_entry *pde;
+
+	pde = proc_create_single_data(DEVICE_NAME, 0444, NULL,
+			ps3vram_proc_show, priv);
+	if (!pde)
+		dev_warn(&dev->core, "failed to create /proc entry\n");
+}
+
+static struct bio *ps3vram_do_bio(struct ps3_system_bus_device *dev,
+				  struct bio *bio)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	int write = bio_data_dir(bio) == WRITE;
+	const char *op = write ? "write" : "read";
+	loff_t offset = bio->bi_iter.bi_sector << 9;
+	blk_status_t error = 0;
+	struct bio_vec bvec;
+	struct bvec_iter iter;
+	struct bio *next;
+
+	bio_for_each_segment(bvec, bio, iter) {
+		/* PS3 is ppc64, so we don't handle highmem */
+		char *ptr = bvec_virt(&bvec);
+		size_t len = bvec.bv_len, retlen;
+
+		dev_dbg(&dev->core, "    %s %zu bytes at offset %llu\n", op,
+			len, offset);
+		if (write)
+			error = ps3vram_write(dev, offset, len, &retlen, ptr);
+		else
+			error = ps3vram_read(dev, offset, len, &retlen, ptr);
+
+		if (error) {
+			dev_err(&dev->core, "%s failed\n", op);
+			goto out;
+		}
+
+		if (retlen != len) {
+			dev_err(&dev->core, "Short %s\n", op);
+			error = BLK_STS_IOERR;
+			goto out;
+		}
+
+		offset += len;
+	}
+
+	dev_dbg(&dev->core, "%s completed\n", op);
+
+out:
+	spin_lock_irq(&priv->lock);
+	bio_list_pop(&priv->list);
+	next = bio_list_peek(&priv->list);
+	spin_unlock_irq(&priv->lock);
+
+	bio->bi_status = error;
+	bio_endio(bio);
+	return next;
+}
+
+static void ps3vram_submit_bio(struct bio *bio)
+{
+	struct ps3_system_bus_device *dev = bio->bi_bdev->bd_disk->private_data;
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+	int busy;
+
+	dev_dbg(&dev->core, "%s\n", __func__);
+
+	spin_lock_irq(&priv->lock);
+	busy = !bio_list_empty(&priv->list);
+	bio_list_add(&priv->list, bio);
+	spin_unlock_irq(&priv->lock);
+
+	if (busy)
+		return;
+
+	do {
+		bio = ps3vram_do_bio(dev, bio);
+	} while (bio);
+}
+
+static const struct block_device_operations ps3vram_fops = {
+	.owner		= THIS_MODULE,
+	.submit_bio	= ps3vram_submit_bio,
+};
+
+static int ps3vram_probe(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv;
+	int error, status;
+	struct gendisk *gendisk;
+	u64 ddr_size, ddr_lpar, ctrl_lpar, info_lpar, reports_lpar,
+	    reports_size, xdr_lpar;
+	char *rest;
+
+	priv = kzalloc_obj(*priv);
+	if (!priv) {
+		error = -ENOMEM;
+		goto fail;
+	}
+
+	spin_lock_init(&priv->lock);
+	bio_list_init(&priv->list);
+	ps3_system_bus_set_drvdata(dev, priv);
+
+	/* Allocate XDR buffer (1MiB aligned) */
+	priv->xdr_buf = (void *)__get_free_pages(GFP_KERNEL,
+		get_order(XDR_BUF_SIZE));
+	if (priv->xdr_buf == NULL) {
+		dev_err(&dev->core, "Could not allocate XDR buffer\n");
+		error = -ENOMEM;
+		goto fail_free_priv;
+	}
+
+	/* Put FIFO at begginning of XDR buffer */
+	priv->fifo_base = (u32 *) (priv->xdr_buf + FIFO_OFFSET);
+	priv->fifo_ptr = priv->fifo_base;
+
+	/* XXX: Need to open GPU, in case ps3fb or snd_ps3 aren't loaded */
+	if (ps3_open_hv_device(dev)) {
+		dev_err(&dev->core, "ps3_open_hv_device failed\n");
+		error = -EAGAIN;
+		goto out_free_xdr_buf;
+	}
+
+	/* Request memory */
+	status = -1;
+	ddr_size = ALIGN(memparse(size, &rest), 1024*1024);
+	if (!ddr_size) {
+		dev_err(&dev->core, "Specified size is too small\n");
+		error = -EINVAL;
+		goto out_close_gpu;
+	}
+
+	while (ddr_size > 0) {
+		status = lv1_gpu_memory_allocate(ddr_size, 0, 0, 0, 0,
+						 &priv->memory_handle,
+						 &ddr_lpar);
+		if (!status)
+			break;
+		ddr_size -= 1024*1024;
+	}
+	if (status) {
+		dev_err(&dev->core, "lv1_gpu_memory_allocate failed %d\n",
+			status);
+		error = -ENOMEM;
+		goto out_close_gpu;
+	}
+
+	/* Request context */
+	status = lv1_gpu_context_allocate(priv->memory_handle, 0,
+					  &priv->context_handle, &ctrl_lpar,
+					  &info_lpar, &reports_lpar,
+					  &reports_size);
+	if (status) {
+		dev_err(&dev->core, "lv1_gpu_context_allocate failed %d\n",
+			status);
+		error = -ENOMEM;
+		goto out_free_memory;
+	}
+
+	/* Map XDR buffer to RSX */
+	xdr_lpar = ps3_mm_phys_to_lpar(__pa(priv->xdr_buf));
+	status = lv1_gpu_context_iomap(priv->context_handle, XDR_IOIF,
+				       xdr_lpar, XDR_BUF_SIZE,
+				       CBE_IOPTE_PP_W | CBE_IOPTE_PP_R |
+				       CBE_IOPTE_M);
+	if (status) {
+		dev_err(&dev->core, "lv1_gpu_context_iomap failed %d\n",
+			status);
+		error = -ENOMEM;
+		goto out_free_context;
+	}
+
+	priv->ctrl = ioremap(ctrl_lpar, 64 * 1024);
+	if (!priv->ctrl) {
+		dev_err(&dev->core, "ioremap CTRL failed\n");
+		error = -ENOMEM;
+		goto out_unmap_context;
+	}
+
+	priv->reports = ioremap(reports_lpar, reports_size);
+	if (!priv->reports) {
+		dev_err(&dev->core, "ioremap REPORTS failed\n");
+		error = -ENOMEM;
+		goto out_unmap_ctrl;
+	}
+
+	mutex_lock(&ps3_gpu_mutex);
+	ps3vram_init_ring(dev);
+	mutex_unlock(&ps3_gpu_mutex);
+
+	priv->size = ddr_size;
+
+	ps3vram_bind(dev);
+
+	mutex_lock(&ps3_gpu_mutex);
+	error = ps3vram_wait_ring(dev, 100);
+	mutex_unlock(&ps3_gpu_mutex);
+	if (error < 0) {
+		dev_err(&dev->core, "Failed to initialize channels\n");
+		error = -ETIMEDOUT;
+		goto out_unmap_reports;
+	}
+
+	error = ps3vram_cache_init(dev);
+	if (error < 0) {
+		goto out_unmap_reports;
+	}
+
+	ps3vram_proc_init(dev);
+
+	gendisk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(gendisk)) {
+		dev_err(&dev->core, "blk_alloc_disk failed\n");
+		error = PTR_ERR(gendisk);
+		goto out_cache_cleanup;
+	}
+
+	priv->gendisk = gendisk;
+	gendisk->major = ps3vram_major;
+	gendisk->minors = 1;
+	gendisk->flags |= GENHD_FL_NO_PART;
+	gendisk->fops = &ps3vram_fops;
+	gendisk->private_data = dev;
+	strscpy(gendisk->disk_name, DEVICE_NAME, sizeof(gendisk->disk_name));
+	set_capacity(gendisk, priv->size >> 9);
+
+	dev_info(&dev->core, "%s: Using %llu MiB of GPU memory\n",
+		 gendisk->disk_name, get_capacity(gendisk) >> 11);
+
+	error = device_add_disk(&dev->core, gendisk, NULL);
+	if (error)
+		goto out_cleanup_disk;
+
+	return 0;
+
+out_cleanup_disk:
+	put_disk(gendisk);
+out_cache_cleanup:
+	remove_proc_entry(DEVICE_NAME, NULL);
+	ps3vram_cache_cleanup(dev);
+out_unmap_reports:
+	iounmap(priv->reports);
+out_unmap_ctrl:
+	iounmap(priv->ctrl);
+out_unmap_context:
+	lv1_gpu_context_iomap(priv->context_handle, XDR_IOIF, xdr_lpar,
+			      XDR_BUF_SIZE, CBE_IOPTE_M);
+out_free_context:
+	lv1_gpu_context_free(priv->context_handle);
+out_free_memory:
+	lv1_gpu_memory_free(priv->memory_handle);
+out_close_gpu:
+	ps3_close_hv_device(dev);
+out_free_xdr_buf:
+	free_pages((unsigned long) priv->xdr_buf, get_order(XDR_BUF_SIZE));
+fail_free_priv:
+	kfree(priv);
+	ps3_system_bus_set_drvdata(dev, NULL);
+fail:
+	return error;
+}
+
+static void ps3vram_remove(struct ps3_system_bus_device *dev)
+{
+	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
+
+	del_gendisk(priv->gendisk);
+	put_disk(priv->gendisk);
+	remove_proc_entry(DEVICE_NAME, NULL);
+	ps3vram_cache_cleanup(dev);
+	iounmap(priv->reports);
+	iounmap(priv->ctrl);
+	lv1_gpu_context_iomap(priv->context_handle, XDR_IOIF,
+			      ps3_mm_phys_to_lpar(__pa(priv->xdr_buf)),
+			      XDR_BUF_SIZE, CBE_IOPTE_M);
+	lv1_gpu_context_free(priv->context_handle);
+	lv1_gpu_memory_free(priv->memory_handle);
+	ps3_close_hv_device(dev);
+	free_pages((unsigned long) priv->xdr_buf, get_order(XDR_BUF_SIZE));
+	kfree(priv);
+	ps3_system_bus_set_drvdata(dev, NULL);
+}
+
+static struct ps3_system_bus_driver ps3vram = {
+	.match_id	= PS3_MATCH_ID_GPU,
+	.match_sub_id	= PS3_MATCH_SUB_ID_GPU_RAMDISK,
+	.core.name	= DEVICE_NAME,
+	.core.owner	= THIS_MODULE,
+	.probe		= ps3vram_probe,
+	.remove		= ps3vram_remove,
+	.shutdown	= ps3vram_remove,
+};
+
+
+static int __init ps3vram_init(void)
+{
+	int error;
+
+	if (!firmware_has_feature(FW_FEATURE_PS3_LV1))
+		return -ENODEV;
+
+	error = register_blkdev(0, DEVICE_NAME);
+	if (error <= 0) {
+		pr_err("%s: register_blkdev failed %d\n", DEVICE_NAME, error);
+		return error;
+	}
+	ps3vram_major = error;
+
+	pr_info("%s: registered block device major %d\n", DEVICE_NAME,
+		ps3vram_major);
+
+	error = ps3_system_bus_driver_register(&ps3vram);
+	if (error)
+		unregister_blkdev(ps3vram_major, DEVICE_NAME);
+
+	return error;
+}
+
+static void __exit ps3vram_exit(void)
+{
+	ps3_system_bus_driver_unregister(&ps3vram);
+	unregister_blkdev(ps3vram_major, DEVICE_NAME);
+}
+
+module_init(ps3vram_init);
+module_exit(ps3vram_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PS3 Video RAM Storage Driver");
+MODULE_AUTHOR("Sony Corporation");
+MODULE_ALIAS(PS3_MODULE_ALIAS_GPU_RAMDISK);