text: /*
   * SPU file system -- file contents
   *
   * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
   *
   * Author: Arnd Bergmann <arndb@de.ibm.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2, or (at your option)
   * any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  #undef DEBUG
  
  #include <linux/fs.h>
  #include <linux/ioctl.h>
  #include <linux/export.h>
  #include <linux/pagemap.h>
  #include <linux/poll.h>
  #include <linux/ptrace.h>
  #include <linux/seq_file.h>
  #include <linux/slab.h>
  
  #include <asm/io.h>
  #include <asm/time.h>
  #include <asm/spu.h>
  #include <asm/spu_info.h>
  #include <asm/uaccess.h>
  
  #include "spufs.h"
  #include "sputrace.h"
  
  #define SPUFS_MMAP_4K (PAGE_SIZE == 0x1000)
  
  /* Simple attribute files */
  struct spufs_attr {
  	int (*get)(void *, u64 *);
  	int (*set)(void *, u64);
  	char get_buf[24];       /* enough to store a u64 and "\n\0" */
  	char set_buf[24];
  	void *data;
  	const char *fmt;        /* format for read operation */
  	struct mutex mutex;     /* protects access to these buffers */
  };
  
  static int spufs_attr_open(struct inode *inode, struct file *file,
  		int (*get)(void *, u64 *), int (*set)(void *, u64),
  		const char *fmt)
  {
  	struct spufs_attr *attr;
  
  	attr = kmalloc(sizeof(*attr), GFP_KERNEL);
  	if (!attr)
  		return -ENOMEM;
  
  	attr->get = get;
  	attr->set = set;
  	attr->data = inode->i_private;
  	attr->fmt = fmt;
  	mutex_init(&attr->mutex);
  	file->private_data = attr;
  
  	return nonseekable_open(inode, file);
  }
  
  static int spufs_attr_release(struct inode *inode, struct file *file)
  {
         kfree(file->private_data);
  	return 0;
  }
  
  static ssize_t spufs_attr_read(struct file *file, char __user *buf,
  		size_t len, loff_t *ppos)
  {
  	struct spufs_attr *attr;
  	size_t size;
  	ssize_t ret;
  
  	attr = file->private_data;
  	if (!attr->get)
  		return -EACCES;
  
  	ret = mutex_lock_interruptible(&attr->mutex);
  	if (ret)
  		return ret;
  
  	if (*ppos) {		/* continued read */
  		size = strlen(attr->get_buf);
  	} else {		/* first read */
  		u64 val;
  		ret = attr->get(attr->data, &val);
  		if (ret)
  			goto out;
  
  		size = scnprintf(attr->get_buf, sizeof(attr->get_buf),
  				 attr->fmt, (unsigned long long)val);
  	}
  
  	ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size);
  out:
  	mutex_unlock(&attr->mutex);
  	return ret;
  }
  
  static ssize_t spufs_attr_write(struct file *file, const char __user *buf,
  		size_t len, loff_t *ppos)
  {
  	struct spufs_attr *attr;
  	u64 val;
  	size_t size;
  	ssize_t ret;
  
  	attr = file->private_data;
  	if (!attr->set)
  		return -EACCES;
  
  	ret = mutex_lock_interruptible(&attr->mutex);
  	if (ret)
  		return ret;
  
  	ret = -EFAULT;
  	size = min(sizeof(attr->set_buf) - 1, len);
  	if (copy_from_user(attr->set_buf, buf, size))
  		goto out;
  
  	ret = len; /* claim we got the whole input */
  	attr->set_buf[size] = '\0';
  	val = simple_strtol(attr->set_buf, NULL, 0);
  	attr->set(attr->data, val);
  out:
  	mutex_unlock(&attr->mutex);
  	return ret;
  }
  
  #define DEFINE_SPUFS_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt)	\
  static int __fops ## _open(struct inode *inode, struct file *file)	\
  {									\
  	__simple_attr_check_format(__fmt, 0ull);			\
  	return spufs_attr_open(inode, file, __get, __set, __fmt);	\
  }									\
  static const struct file_operations __fops = {				\
  	.open	 = __fops ## _open,					\
  	.release = spufs_attr_release,					\
  	.read	 = spufs_attr_read,					\
  	.write	 = spufs_attr_write,					\
  	.llseek  = generic_file_llseek,					\
  };
  
  
  static int
  spufs_mem_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	file->private_data = ctx;
  	if (!i->i_openers++)
  		ctx->local_store = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static int
  spufs_mem_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->local_store = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static ssize_t
  __spufs_mem_read(struct spu_context *ctx, char __user *buffer,
  			size_t size, loff_t *pos)
  {
  	char *local_store = ctx->ops->get_ls(ctx);
  	return simple_read_from_buffer(buffer, size, pos, local_store,
  					LS_SIZE);
  }
  
  static ssize_t
  spufs_mem_read(struct file *file, char __user *buffer,
  				size_t size, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	ssize_t ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ret = __spufs_mem_read(ctx, buffer, size, pos);
  	spu_release(ctx);
  
  	return ret;
  }
  
  static ssize_t
  spufs_mem_write(struct file *file, const char __user *buffer,
  					size_t size, loff_t *ppos)
  {
  	struct spu_context *ctx = file->private_data;
  	char *local_store;
  	loff_t pos = *ppos;
  	int ret;
  
  	if (pos > LS_SIZE)
  		return -EFBIG;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  
  	local_store = ctx->ops->get_ls(ctx);
  	size = simple_write_to_buffer(local_store, LS_SIZE, ppos, buffer, size);
  	spu_release(ctx);
  
  	return size;
  }
  
  static int
  spufs_mem_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  {
  	struct spu_context *ctx	= vma->vm_file->private_data;
  	unsigned long address = (unsigned long)vmf->virtual_address;
  	unsigned long pfn, offset;
  
  	offset = vmf->pgoff << PAGE_SHIFT;
  	if (offset >= LS_SIZE)
  		return VM_FAULT_SIGBUS;
  
  	pr_debug("spufs_mem_mmap_fault address=0x%lx, offset=0x%lx\n",
  			address, offset);
  
  	if (spu_acquire(ctx))
  		return VM_FAULT_NOPAGE;
  
  	if (ctx->state == SPU_STATE_SAVED) {
  		vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);
  		pfn = vmalloc_to_pfn(ctx->csa.lscsa->ls + offset);
  	} else {
  		vma->vm_page_prot = pgprot_noncached_wc(vma->vm_page_prot);
  		pfn = (ctx->spu->local_store_phys + offset) >> PAGE_SHIFT;
  	}
  	vm_insert_pfn(vma, address, pfn);
  
  	spu_release(ctx);
  
  	return VM_FAULT_NOPAGE;
  }
  
  static int spufs_mem_mmap_access(struct vm_area_struct *vma,
  				unsigned long address,
  				void *buf, int len, int write)
  {
  	struct spu_context *ctx = vma->vm_file->private_data;
  	unsigned long offset = address - vma->vm_start;
  	char *local_store;
  
  	if (write && !(vma->vm_flags & VM_WRITE))
  		return -EACCES;
  	if (spu_acquire(ctx))
  		return -EINTR;
  	if ((offset + len) > vma->vm_end)
  		len = vma->vm_end - offset;
  	local_store = ctx->ops->get_ls(ctx);
  	if (write)
  		memcpy_toio(local_store + offset, buf, len);
  	else
  		memcpy_fromio(buf, local_store + offset, len);
  	spu_release(ctx);
  	return len;
  }
  
  static const struct vm_operations_struct spufs_mem_mmap_vmops = {
  	.fault = spufs_mem_mmap_fault,
  	.access = spufs_mem_mmap_access,
  };
  
  static int spufs_mem_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached_wc(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_mem_mmap_vmops;
  	return 0;
  }
  
  static const struct file_operations spufs_mem_fops = {
  	.open			= spufs_mem_open,
  	.release		= spufs_mem_release,
  	.read			= spufs_mem_read,
  	.write			= spufs_mem_write,
  	.llseek			= generic_file_llseek,
  	.mmap			= spufs_mem_mmap,
  };
  
  static int spufs_ps_fault(struct vm_area_struct *vma,
  				    struct vm_fault *vmf,
  				    unsigned long ps_offs,
  				    unsigned long ps_size)
  {
  	struct spu_context *ctx = vma->vm_file->private_data;
  	unsigned long area, offset = vmf->pgoff << PAGE_SHIFT;
  	int ret = 0;
  
  	spu_context_nospu_trace(spufs_ps_fault__enter, ctx);
  
  	if (offset >= ps_size)
  		return VM_FAULT_SIGBUS;
  
  	if (fatal_signal_pending(current))
  		return VM_FAULT_SIGBUS;
  
  	/*
  	 * Because we release the mmap_sem, the context may be destroyed while
  	 * we're in spu_wait. Grab an extra reference so it isn't destroyed
  	 * in the meantime.
  	 */
  	get_spu_context(ctx);
  
  	/*
  	 * We have to wait for context to be loaded before we have
  	 * pages to hand out to the user, but we don't want to wait
  	 * with the mmap_sem held.
  	 * It is possible to drop the mmap_sem here, but then we need
  	 * to return VM_FAULT_NOPAGE because the mappings may have
  	 * hanged.
  	 */
  	if (spu_acquire(ctx))
  		goto refault;
  
  	if (ctx->state == SPU_STATE_SAVED) {
  		up_read(&current->mm->mmap_sem);
  		spu_context_nospu_trace(spufs_ps_fault__sleep, ctx);
  		ret = spufs_wait(ctx->run_wq, ctx->state == SPU_STATE_RUNNABLE);
  		spu_context_trace(spufs_ps_fault__wake, ctx, ctx->spu);
  		down_read(&current->mm->mmap_sem);
  	} else {
  		area = ctx->spu->problem_phys + ps_offs;
  		vm_insert_pfn(vma, (unsigned long)vmf->virtual_address,
  					(area + offset) >> PAGE_SHIFT);
  		spu_context_trace(spufs_ps_fault__insert, ctx, ctx->spu);
  	}
  
  	if (!ret)
  		spu_release(ctx);
  
  refault:
  	put_spu_context(ctx);
  	return VM_FAULT_NOPAGE;
  }
  
  #if SPUFS_MMAP_4K
  static int spufs_cntl_mmap_fault(struct vm_area_struct *vma,
  					   struct vm_fault *vmf)
  {
  	return spufs_ps_fault(vma, vmf, 0x4000, SPUFS_CNTL_MAP_SIZE);
  }
  
  static const struct vm_operations_struct spufs_cntl_mmap_vmops = {
  	.fault = spufs_cntl_mmap_fault,
  };
  
  /*
   * mmap support for problem state control area [0x4000 - 0x4fff].
   */
  static int spufs_cntl_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_cntl_mmap_vmops;
  	return 0;
  }
  #else /* SPUFS_MMAP_4K */
  #define spufs_cntl_mmap NULL
  #endif /* !SPUFS_MMAP_4K */
  
  static int spufs_cntl_get(void *data, u64 *val)
  {
  	struct spu_context *ctx = data;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	*val = ctx->ops->status_read(ctx);
  	spu_release(ctx);
  
  	return 0;
  }
  
  static int spufs_cntl_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ctx->ops->runcntl_write(ctx, val);
  	spu_release(ctx);
  
  	return 0;
  }
  
  static int spufs_cntl_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	file->private_data = ctx;
  	if (!i->i_openers++)
  		ctx->cntl = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return simple_attr_open(inode, file, spufs_cntl_get,
  					spufs_cntl_set, "0x%08lx");
  }
  
  static int
  spufs_cntl_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	simple_attr_release(inode, file);
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->cntl = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static const struct file_operations spufs_cntl_fops = {
  	.open = spufs_cntl_open,
  	.release = spufs_cntl_release,
  	.read = simple_attr_read,
  	.write = simple_attr_write,
  	.llseek	= generic_file_llseek,
  	.mmap = spufs_cntl_mmap,
  };
  
  static int
  spufs_regs_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	file->private_data = i->i_ctx;
  	return 0;
  }
  
  static ssize_t
  __spufs_regs_read(struct spu_context *ctx, char __user *buffer,
  			size_t size, loff_t *pos)
  {
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	return simple_read_from_buffer(buffer, size, pos,
  				      lscsa->gprs, sizeof lscsa->gprs);
  }
  
  static ssize_t
  spufs_regs_read(struct file *file, char __user *buffer,
  		size_t size, loff_t *pos)
  {
  	int ret;
  	struct spu_context *ctx = file->private_data;
  
  	/* pre-check for file position: if we'd return EOF, there's no point
  	 * causing a deschedule */
  	if (*pos >= sizeof(ctx->csa.lscsa->gprs))
  		return 0;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	ret = __spufs_regs_read(ctx, buffer, size, pos);
  	spu_release_saved(ctx);
  	return ret;
  }
  
  static ssize_t
  spufs_regs_write(struct file *file, const char __user *buffer,
  		 size_t size, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	int ret;
  
  	if (*pos >= sizeof(lscsa->gprs))
  		return -EFBIG;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  
  	size = simple_write_to_buffer(lscsa->gprs, sizeof(lscsa->gprs), pos,
  					buffer, size);
  
  	spu_release_saved(ctx);
  	return size;
  }
  
  static const struct file_operations spufs_regs_fops = {
  	.open	 = spufs_regs_open,
  	.read    = spufs_regs_read,
  	.write   = spufs_regs_write,
  	.llseek  = generic_file_llseek,
  };
  
  static ssize_t
  __spufs_fpcr_read(struct spu_context *ctx, char __user * buffer,
  			size_t size, loff_t * pos)
  {
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	return simple_read_from_buffer(buffer, size, pos,
  				      &lscsa->fpcr, sizeof(lscsa->fpcr));
  }
  
  static ssize_t
  spufs_fpcr_read(struct file *file, char __user * buffer,
  		size_t size, loff_t * pos)
  {
  	int ret;
  	struct spu_context *ctx = file->private_data;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	ret = __spufs_fpcr_read(ctx, buffer, size, pos);
  	spu_release_saved(ctx);
  	return ret;
  }
  
  static ssize_t
  spufs_fpcr_write(struct file *file, const char __user * buffer,
  		 size_t size, loff_t * pos)
  {
  	struct spu_context *ctx = file->private_data;
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	int ret;
  
  	if (*pos >= sizeof(lscsa->fpcr))
  		return -EFBIG;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  
  	size = simple_write_to_buffer(&lscsa->fpcr, sizeof(lscsa->fpcr), pos,
  					buffer, size);
  
  	spu_release_saved(ctx);
  	return size;
  }
  
  static const struct file_operations spufs_fpcr_fops = {
  	.open = spufs_regs_open,
  	.read = spufs_fpcr_read,
  	.write = spufs_fpcr_write,
  	.llseek = generic_file_llseek,
  };
  
  /* generic open function for all pipe-like files */
  static int spufs_pipe_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	file->private_data = i->i_ctx;
  
  	return nonseekable_open(inode, file);
  }
  
  /*
   * Read as many bytes from the mailbox as possible, until
   * one of the conditions becomes true:
   *
   * - no more data available in the mailbox
   * - end of the user provided buffer
   * - end of the mapped area
   */
  static ssize_t spufs_mbox_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	u32 mbox_data, __user *udata;
  	ssize_t count;
  
  	if (len < 4)
  		return -EINVAL;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	udata = (void __user *)buf;
  
  	count = spu_acquire(ctx);
  	if (count)
  		return count;
  
  	for (count = 0; (count + 4) <= len; count += 4, udata++) {
  		int ret;
  		ret = ctx->ops->mbox_read(ctx, &mbox_data);
  		if (ret == 0)
  			break;
  
  		/*
  		 * at the end of the mapped area, we can fault
  		 * but still need to return the data we have
  		 * read successfully so far.
  		 */
  		ret = __put_user(mbox_data, udata);
  		if (ret) {
  			if (!count)
  				count = -EFAULT;
  			break;
  		}
  	}
  	spu_release(ctx);
  
  	if (!count)
  		count = -EAGAIN;
  
  	return count;
  }
  
  static const struct file_operations spufs_mbox_fops = {
  	.open	= spufs_pipe_open,
  	.read	= spufs_mbox_read,
  	.llseek	= no_llseek,
  };
  
  static ssize_t spufs_mbox_stat_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	ssize_t ret;
  	u32 mbox_stat;
  
  	if (len < 4)
  		return -EINVAL;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  
  	mbox_stat = ctx->ops->mbox_stat_read(ctx) & 0xff;
  
  	spu_release(ctx);
  
  	if (copy_to_user(buf, &mbox_stat, sizeof mbox_stat))
  		return -EFAULT;
  
  	return 4;
  }
  
  static const struct file_operations spufs_mbox_stat_fops = {
  	.open	= spufs_pipe_open,
  	.read	= spufs_mbox_stat_read,
  	.llseek = no_llseek,
  };
  
  /* low-level ibox access function */
  size_t spu_ibox_read(struct spu_context *ctx, u32 *data)
  {
  	return ctx->ops->ibox_read(ctx, data);
  }
  
  static int spufs_ibox_fasync(int fd, struct file *file, int on)
  {
  	struct spu_context *ctx = file->private_data;
  
  	return fasync_helper(fd, file, on, &ctx->ibox_fasync);
  }
  
  /* interrupt-level ibox callback function. */
  void spufs_ibox_callback(struct spu *spu)
  {
  	struct spu_context *ctx = spu->ctx;
  
  	if (!ctx)
  		return;
  
  	wake_up_all(&ctx->ibox_wq);
  	kill_fasync(&ctx->ibox_fasync, SIGIO, POLLIN);
  }
  
  /*
   * Read as many bytes from the interrupt mailbox as possible, until
   * one of the conditions becomes true:
   *
   * - no more data available in the mailbox
   * - end of the user provided buffer
   * - end of the mapped area
   *
   * If the file is opened without O_NONBLOCK, we wait here until
   * any data is available, but return when we have been able to
   * read something.
   */
  static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	u32 ibox_data, __user *udata;
  	ssize_t count;
  
  	if (len < 4)
  		return -EINVAL;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	udata = (void __user *)buf;
  
  	count = spu_acquire(ctx);
  	if (count)
  		goto out;
  
  	/* wait only for the first element */
  	count = 0;
  	if (file->f_flags & O_NONBLOCK) {
  		if (!spu_ibox_read(ctx, &ibox_data)) {
  			count = -EAGAIN;
  			goto out_unlock;
  		}
  	} else {
  		count = spufs_wait(ctx->ibox_wq, spu_ibox_read(ctx, &ibox_data));
  		if (count)
  			goto out;
  	}
  
  	/* if we can't write at all, return -EFAULT */
  	count = __put_user(ibox_data, udata);
  	if (count)
  		goto out_unlock;
  
  	for (count = 4, udata++; (count + 4) <= len; count += 4, udata++) {
  		int ret;
  		ret = ctx->ops->ibox_read(ctx, &ibox_data);
  		if (ret == 0)
  			break;
  		/*
  		 * at the end of the mapped area, we can fault
  		 * but still need to return the data we have
  		 * read successfully so far.
  		 */
  		ret = __put_user(ibox_data, udata);
  		if (ret)
  			break;
  	}
  
  out_unlock:
  	spu_release(ctx);
  out:
  	return count;
  }
  
  static unsigned int spufs_ibox_poll(struct file *file, poll_table *wait)
  {
  	struct spu_context *ctx = file->private_data;
  	unsigned int mask;
  
  	poll_wait(file, &ctx->ibox_wq, wait);
  
  	/*
  	 * For now keep this uninterruptible and also ignore the rule
  	 * that poll should not sleep.  Will be fixed later.
  	 */
  	mutex_lock(&ctx->state_mutex);
  	mask = ctx->ops->mbox_stat_poll(ctx, POLLIN | POLLRDNORM);
  	spu_release(ctx);
  
  	return mask;
  }
  
  static const struct file_operations spufs_ibox_fops = {
  	.open	= spufs_pipe_open,
  	.read	= spufs_ibox_read,
  	.poll	= spufs_ibox_poll,
  	.fasync	= spufs_ibox_fasync,
  	.llseek = no_llseek,
  };
  
  static ssize_t spufs_ibox_stat_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	ssize_t ret;
  	u32 ibox_stat;
  
  	if (len < 4)
  		return -EINVAL;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ibox_stat = (ctx->ops->mbox_stat_read(ctx) >> 16) & 0xff;
  	spu_release(ctx);
  
  	if (copy_to_user(buf, &ibox_stat, sizeof ibox_stat))
  		return -EFAULT;
  
  	return 4;
  }
  
  static const struct file_operations spufs_ibox_stat_fops = {
  	.open	= spufs_pipe_open,
  	.read	= spufs_ibox_stat_read,
  	.llseek = no_llseek,
  };
  
  /* low-level mailbox write */
  size_t spu_wbox_write(struct spu_context *ctx, u32 data)
  {
  	return ctx->ops->wbox_write(ctx, data);
  }
  
  static int spufs_wbox_fasync(int fd, struct file *file, int on)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	ret = fasync_helper(fd, file, on, &ctx->wbox_fasync);
  
  	return ret;
  }
  
  /* interrupt-level wbox callback function. */
  void spufs_wbox_callback(struct spu *spu)
  {
  	struct spu_context *ctx = spu->ctx;
  
  	if (!ctx)
  		return;
  
  	wake_up_all(&ctx->wbox_wq);
  	kill_fasync(&ctx->wbox_fasync, SIGIO, POLLOUT);
  }
  
  /*
   * Write as many bytes to the interrupt mailbox as possible, until
   * one of the conditions becomes true:
   *
   * - the mailbox is full
   * - end of the user provided buffer
   * - end of the mapped area
   *
   * If the file is opened without O_NONBLOCK, we wait here until
   * space is available, but return when we have been able to
   * write something.
   */
  static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	u32 wbox_data, __user *udata;
  	ssize_t count;
  
  	if (len < 4)
  		return -EINVAL;
  
  	udata = (void __user *)buf;
  	if (!access_ok(VERIFY_READ, buf, len))
  		return -EFAULT;
  
  	if (__get_user(wbox_data, udata))
  		return -EFAULT;
  
  	count = spu_acquire(ctx);
  	if (count)
  		goto out;
  
  	/*
  	 * make sure we can at least write one element, by waiting
  	 * in case of !O_NONBLOCK
  	 */
  	count = 0;
  	if (file->f_flags & O_NONBLOCK) {
  		if (!spu_wbox_write(ctx, wbox_data)) {
  			count = -EAGAIN;
  			goto out_unlock;
  		}
  	} else {
  		count = spufs_wait(ctx->wbox_wq, spu_wbox_write(ctx, wbox_data));
  		if (count)
  			goto out;
  	}
  
  
  	/* write as much as possible */
  	for (count = 4, udata++; (count + 4) <= len; count += 4, udata++) {
  		int ret;
  		ret = __get_user(wbox_data, udata);
  		if (ret)
  			break;
  
  		ret = spu_wbox_write(ctx, wbox_data);
  		if (ret == 0)
  			break;
  	}
  
  out_unlock:
  	spu_release(ctx);
  out:
  	return count;
  }
  
  static unsigned int spufs_wbox_poll(struct file *file, poll_table *wait)
  {
  	struct spu_context *ctx = file->private_data;
  	unsigned int mask;
  
  	poll_wait(file, &ctx->wbox_wq, wait);
  
  	/*
  	 * For now keep this uninterruptible and also ignore the rule
  	 * that poll should not sleep.  Will be fixed later.
  	 */
  	mutex_lock(&ctx->state_mutex);
  	mask = ctx->ops->mbox_stat_poll(ctx, POLLOUT | POLLWRNORM);
  	spu_release(ctx);
  
  	return mask;
  }
  
  static const struct file_operations spufs_wbox_fops = {
  	.open	= spufs_pipe_open,
  	.write	= spufs_wbox_write,
  	.poll	= spufs_wbox_poll,
  	.fasync	= spufs_wbox_fasync,
  	.llseek = no_llseek,
  };
  
  static ssize_t spufs_wbox_stat_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	ssize_t ret;
  	u32 wbox_stat;
  
  	if (len < 4)
  		return -EINVAL;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	wbox_stat = (ctx->ops->mbox_stat_read(ctx) >> 8) & 0xff;
  	spu_release(ctx);
  
  	if (copy_to_user(buf, &wbox_stat, sizeof wbox_stat))
  		return -EFAULT;
  
  	return 4;
  }
  
  static const struct file_operations spufs_wbox_stat_fops = {
  	.open	= spufs_pipe_open,
  	.read	= spufs_wbox_stat_read,
  	.llseek = no_llseek,
  };
  
  static int spufs_signal1_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	file->private_data = ctx;
  	if (!i->i_openers++)
  		ctx->signal1 = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return nonseekable_open(inode, file);
  }
  
  static int
  spufs_signal1_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->signal1 = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static ssize_t __spufs_signal1_read(struct spu_context *ctx, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	int ret = 0;
  	u32 data;
  
  	if (len < 4)
  		return -EINVAL;
  
  	if (ctx->csa.spu_chnlcnt_RW[3]) {
  		data = ctx->csa.spu_chnldata_RW[3];
  		ret = 4;
  	}
  
  	if (!ret)
  		goto out;
  
  	if (copy_to_user(buf, &data, 4))
  		return -EFAULT;
  
  out:
  	return ret;
  }
  
  static ssize_t spufs_signal1_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	int ret;
  	struct spu_context *ctx = file->private_data;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	ret = __spufs_signal1_read(ctx, buf, len, pos);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static ssize_t spufs_signal1_write(struct file *file, const char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx;
  	ssize_t ret;
  	u32 data;
  
  	ctx = file->private_data;
  
  	if (len < 4)
  		return -EINVAL;
  
  	if (copy_from_user(&data, buf, 4))
  		return -EFAULT;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ctx->ops->signal1_write(ctx, data);
  	spu_release(ctx);
  
  	return 4;
  }
  
  static int
  spufs_signal1_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  {
  #if SPUFS_SIGNAL_MAP_SIZE == 0x1000
  	return spufs_ps_fault(vma, vmf, 0x14000, SPUFS_SIGNAL_MAP_SIZE);
  #elif SPUFS_SIGNAL_MAP_SIZE == 0x10000
  	/* For 64k pages, both signal1 and signal2 can be used to mmap the whole
  	 * signal 1 and 2 area
  	 */
  	return spufs_ps_fault(vma, vmf, 0x10000, SPUFS_SIGNAL_MAP_SIZE);
  #else
  #error unsupported page size
  #endif
  }
  
  static const struct vm_operations_struct spufs_signal1_mmap_vmops = {
  	.fault = spufs_signal1_mmap_fault,
  };
  
  static int spufs_signal1_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_signal1_mmap_vmops;
  	return 0;
  }
  
  static const struct file_operations spufs_signal1_fops = {
  	.open = spufs_signal1_open,
  	.release = spufs_signal1_release,
  	.read = spufs_signal1_read,
  	.write = spufs_signal1_write,
  	.mmap = spufs_signal1_mmap,
  	.llseek = no_llseek,
  };
  
  static const struct file_operations spufs_signal1_nosched_fops = {
  	.open = spufs_signal1_open,
  	.release = spufs_signal1_release,
  	.write = spufs_signal1_write,
  	.mmap = spufs_signal1_mmap,
  	.llseek = no_llseek,
  };
  
  static int spufs_signal2_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	file->private_data = ctx;
  	if (!i->i_openers++)
  		ctx->signal2 = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return nonseekable_open(inode, file);
  }
  
  static int
  spufs_signal2_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->signal2 = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static ssize_t __spufs_signal2_read(struct spu_context *ctx, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	int ret = 0;
  	u32 data;
  
  	if (len < 4)
  		return -EINVAL;
  
  	if (ctx->csa.spu_chnlcnt_RW[4]) {
  		data =  ctx->csa.spu_chnldata_RW[4];
  		ret = 4;
  	}
  
  	if (!ret)
  		goto out;
  
  	if (copy_to_user(buf, &data, 4))
  		return -EFAULT;
  
  out:
  	return ret;
  }
  
  static ssize_t spufs_signal2_read(struct file *file, char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	ret = __spufs_signal2_read(ctx, buf, len, pos);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static ssize_t spufs_signal2_write(struct file *file, const char __user *buf,
  			size_t len, loff_t *pos)
  {
  	struct spu_context *ctx;
  	ssize_t ret;
  	u32 data;
  
  	ctx = file->private_data;
  
  	if (len < 4)
  		return -EINVAL;
  
  	if (copy_from_user(&data, buf, 4))
  		return -EFAULT;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ctx->ops->signal2_write(ctx, data);
  	spu_release(ctx);
  
  	return 4;
  }
  
  #if SPUFS_MMAP_4K
  static int
  spufs_signal2_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  {
  #if SPUFS_SIGNAL_MAP_SIZE == 0x1000
  	return spufs_ps_fault(vma, vmf, 0x1c000, SPUFS_SIGNAL_MAP_SIZE);
  #elif SPUFS_SIGNAL_MAP_SIZE == 0x10000
  	/* For 64k pages, both signal1 and signal2 can be used to mmap the whole
  	 * signal 1 and 2 area
  	 */
  	return spufs_ps_fault(vma, vmf, 0x10000, SPUFS_SIGNAL_MAP_SIZE);
  #else
  #error unsupported page size
  #endif
  }
  
  static const struct vm_operations_struct spufs_signal2_mmap_vmops = {
  	.fault = spufs_signal2_mmap_fault,
  };
  
  static int spufs_signal2_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_signal2_mmap_vmops;
  	return 0;
  }
  #else /* SPUFS_MMAP_4K */
  #define spufs_signal2_mmap NULL
  #endif /* !SPUFS_MMAP_4K */
  
  static const struct file_operations spufs_signal2_fops = {
  	.open = spufs_signal2_open,
  	.release = spufs_signal2_release,
  	.read = spufs_signal2_read,
  	.write = spufs_signal2_write,
  	.mmap = spufs_signal2_mmap,
  	.llseek = no_llseek,
  };
  
  static const struct file_operations spufs_signal2_nosched_fops = {
  	.open = spufs_signal2_open,
  	.release = spufs_signal2_release,
  	.write = spufs_signal2_write,
  	.mmap = spufs_signal2_mmap,
  	.llseek = no_llseek,
  };
  
  /*
   * This is a wrapper around DEFINE_SIMPLE_ATTRIBUTE which does the
   * work of acquiring (or not) the SPU context before calling through
   * to the actual get routine. The set routine is called directly.
   */
  #define SPU_ATTR_NOACQUIRE	0
  #define SPU_ATTR_ACQUIRE	1
  #define SPU_ATTR_ACQUIRE_SAVED	2
  
  #define DEFINE_SPUFS_ATTRIBUTE(__name, __get, __set, __fmt, __acquire)	\
  static int __##__get(void *data, u64 *val)				\
  {									\
  	struct spu_context *ctx = data;					\
  	int ret = 0;							\
  									\
  	if (__acquire == SPU_ATTR_ACQUIRE) {				\
  		ret = spu_acquire(ctx);					\
  		if (ret)						\
  			return ret;					\
  		*val = __get(ctx);					\
  		spu_release(ctx);					\
  	} else if (__acquire == SPU_ATTR_ACQUIRE_SAVED)	{		\
  		ret = spu_acquire_saved(ctx);				\
  		if (ret)						\
  			return ret;					\
  		*val = __get(ctx);					\
  		spu_release_saved(ctx);					\
  	} else								\
  		*val = __get(ctx);					\
  									\
  	return 0;							\
  }									\
  DEFINE_SPUFS_SIMPLE_ATTRIBUTE(__name, __##__get, __set, __fmt);
  
  static int spufs_signal1_type_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ctx->ops->signal1_type_set(ctx, val);
  	spu_release(ctx);
  
  	return 0;
  }
  
  static u64 spufs_signal1_type_get(struct spu_context *ctx)
  {
  	return ctx->ops->signal1_type_get(ctx);
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_signal1_type, spufs_signal1_type_get,
  		       spufs_signal1_type_set, "%llu\n", SPU_ATTR_ACQUIRE);
  
  
  static int spufs_signal2_type_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ctx->ops->signal2_type_set(ctx, val);
  	spu_release(ctx);
  
  	return 0;
  }
  
  static u64 spufs_signal2_type_get(struct spu_context *ctx)
  {
  	return ctx->ops->signal2_type_get(ctx);
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_signal2_type, spufs_signal2_type_get,
  		       spufs_signal2_type_set, "%llu\n", SPU_ATTR_ACQUIRE);
  
  #if SPUFS_MMAP_4K
  static int
  spufs_mss_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  {
  	return spufs_ps_fault(vma, vmf, 0x0000, SPUFS_MSS_MAP_SIZE);
  }
  
  static const struct vm_operations_struct spufs_mss_mmap_vmops = {
  	.fault = spufs_mss_mmap_fault,
  };
  
  /*
   * mmap support for problem state MFC DMA area [0x0000 - 0x0fff].
   */
  static int spufs_mss_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_mss_mmap_vmops;
  	return 0;
  }
  #else /* SPUFS_MMAP_4K */
  #define spufs_mss_mmap NULL
  #endif /* !SPUFS_MMAP_4K */
  
  static int spufs_mss_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	file->private_data = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!i->i_openers++)
  		ctx->mss = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return nonseekable_open(inode, file);
  }
  
  static int
  spufs_mss_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->mss = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static const struct file_operations spufs_mss_fops = {
  	.open	 = spufs_mss_open,
  	.release = spufs_mss_release,
  	.mmap	 = spufs_mss_mmap,
  	.llseek  = no_llseek,
  };
  
  static int
  spufs_psmap_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  {
  	return spufs_ps_fault(vma, vmf, 0x0000, SPUFS_PS_MAP_SIZE);
  }
  
  static const struct vm_operations_struct spufs_psmap_mmap_vmops = {
  	.fault = spufs_psmap_mmap_fault,
  };
  
  /*
   * mmap support for full problem state area [0x00000 - 0x1ffff].
   */
  static int spufs_psmap_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_psmap_mmap_vmops;
  	return 0;
  }
  
  static int spufs_psmap_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	file->private_data = i->i_ctx;
  	if (!i->i_openers++)
  		ctx->psmap = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return nonseekable_open(inode, file);
  }
  
  static int
  spufs_psmap_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->psmap = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  static const struct file_operations spufs_psmap_fops = {
  	.open	 = spufs_psmap_open,
  	.release = spufs_psmap_release,
  	.mmap	 = spufs_psmap_mmap,
  	.llseek  = no_llseek,
  };
  
  
  #if SPUFS_MMAP_4K
  static int
  spufs_mfc_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  {
  	return spufs_ps_fault(vma, vmf, 0x3000, SPUFS_MFC_MAP_SIZE);
  }
  
  static const struct vm_operations_struct spufs_mfc_mmap_vmops = {
  	.fault = spufs_mfc_mmap_fault,
  };
  
  /*
   * mmap support for problem state MFC DMA area [0x0000 - 0x0fff].
   */
  static int spufs_mfc_mmap(struct file *file, struct vm_area_struct *vma)
  {
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	vma->vm_flags |= VM_IO | VM_PFNMAP;
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	vma->vm_ops = &spufs_mfc_mmap_vmops;
  	return 0;
  }
  #else /* SPUFS_MMAP_4K */
  #define spufs_mfc_mmap NULL
  #endif /* !SPUFS_MMAP_4K */
  
  static int spufs_mfc_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	/* we don't want to deal with DMA into other processes */
  	if (ctx->owner != current->mm)
  		return -EINVAL;
  
  	if (atomic_read(&inode->i_count) != 1)
  		return -EBUSY;
  
  	mutex_lock(&ctx->mapping_lock);
  	file->private_data = ctx;
  	if (!i->i_openers++)
  		ctx->mfc = inode->i_mapping;
  	mutex_unlock(&ctx->mapping_lock);
  	return nonseekable_open(inode, file);
  }
  
  static int
  spufs_mfc_release(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  
  	mutex_lock(&ctx->mapping_lock);
  	if (!--i->i_openers)
  		ctx->mfc = NULL;
  	mutex_unlock(&ctx->mapping_lock);
  	return 0;
  }
  
  /* interrupt-level mfc callback function. */
  void spufs_mfc_callback(struct spu *spu)
  {
  	struct spu_context *ctx = spu->ctx;
  
  	if (!ctx)
  		return;
  
  	wake_up_all(&ctx->mfc_wq);
  
  	pr_debug("%s %s\n", __func__, spu->name);
  	if (ctx->mfc_fasync) {
  		u32 free_elements, tagstatus;
  		unsigned int mask;
  
  		/* no need for spu_acquire in interrupt context */
  		free_elements = ctx->ops->get_mfc_free_elements(ctx);
  		tagstatus = ctx->ops->read_mfc_tagstatus(ctx);
  
  		mask = 0;
  		if (free_elements & 0xffff)
  			mask |= POLLOUT;
  		if (tagstatus & ctx->tagwait)
  			mask |= POLLIN;
  
  		kill_fasync(&ctx->mfc_fasync, SIGIO, mask);
  	}
  }
  
  static int spufs_read_mfc_tagstatus(struct spu_context *ctx, u32 *status)
  {
  	/* See if there is one tag group is complete */
  	/* FIXME we need locking around tagwait */
  	*status = ctx->ops->read_mfc_tagstatus(ctx) & ctx->tagwait;
  	ctx->tagwait &= ~*status;
  	if (*status)
  		return 1;
  
  	/* enable interrupt waiting for any tag group,
  	   may silently fail if interrupts are already enabled */
  	ctx->ops->set_mfc_query(ctx, ctx->tagwait, 1);
  	return 0;
  }
  
  static ssize_t spufs_mfc_read(struct file *file, char __user *buffer,
  			size_t size, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret = -EINVAL;
  	u32 status;
  
  	if (size != 4)
  		goto out;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  
  	ret = -EINVAL;
  	if (file->f_flags & O_NONBLOCK) {
  		status = ctx->ops->read_mfc_tagstatus(ctx);
  		if (!(status & ctx->tagwait))
  			ret = -EAGAIN;
  		else
  			/* XXX(hch): shouldn't we clear ret here? */
  			ctx->tagwait &= ~status;
  	} else {
  		ret = spufs_wait(ctx->mfc_wq,
  			   spufs_read_mfc_tagstatus(ctx, &status));
  		if (ret)
  			goto out;
  	}
  	spu_release(ctx);
  
  	ret = 4;
  	if (copy_to_user(buffer, &status, 4))
  		ret = -EFAULT;
  
  out:
  	return ret;
  }
  
  static int spufs_check_valid_dma(struct mfc_dma_command *cmd)
  {
  	pr_debug("queueing DMA %x %llx %x %x %x\n", cmd->lsa,
  		 cmd->ea, cmd->size, cmd->tag, cmd->cmd);
  
  	switch (cmd->cmd) {
  	case MFC_PUT_CMD:
  	case MFC_PUTF_CMD:
  	case MFC_PUTB_CMD:
  	case MFC_GET_CMD:
  	case MFC_GETF_CMD:
  	case MFC_GETB_CMD:
  		break;
  	default:
  		pr_debug("invalid DMA opcode %x\n", cmd->cmd);
  		return -EIO;
  	}
  
  	if ((cmd->lsa & 0xf) != (cmd->ea &0xf)) {
  		pr_debug("invalid DMA alignment, ea %llx lsa %x\n",
  				cmd->ea, cmd->lsa);
  		return -EIO;
  	}
  
  	switch (cmd->size & 0xf) {
  	case 1:
  		break;
  	case 2:
  		if (cmd->lsa & 1)
  			goto error;
  		break;
  	case 4:
  		if (cmd->lsa & 3)
  			goto error;
  		break;
  	case 8:
  		if (cmd->lsa & 7)
  			goto error;
  		break;
  	case 0:
  		if (cmd->lsa & 15)
  			goto error;
  		break;
  	error:
  	default:
  		pr_debug("invalid DMA alignment %x for size %x\n",
  			cmd->lsa & 0xf, cmd->size);
  		return -EIO;
  	}
  
  	if (cmd->size > 16 * 1024) {
  		pr_debug("invalid DMA size %x\n", cmd->size);
  		return -EIO;
  	}
  
  	if (cmd->tag & 0xfff0) {
  		/* we reserve the higher tag numbers for kernel use */
  		pr_debug("invalid DMA tag\n");
  		return -EIO;
  	}
  
  	if (cmd->class) {
  		/* not supported in this version */
  		pr_debug("invalid DMA class\n");
  		return -EIO;
  	}
  
  	return 0;
  }
  
  static int spu_send_mfc_command(struct spu_context *ctx,
  				struct mfc_dma_command cmd,
  				int *error)
  {
  	*error = ctx->ops->send_mfc_command(ctx, &cmd);
  	if (*error == -EAGAIN) {
  		/* wait for any tag group to complete
  		   so we have space for the new command */
  		ctx->ops->set_mfc_query(ctx, ctx->tagwait, 1);
  		/* try again, because the queue might be
  		   empty again */
  		*error = ctx->ops->send_mfc_command(ctx, &cmd);
  		if (*error == -EAGAIN)
  			return 0;
  	}
  	return 1;
  }
  
  static ssize_t spufs_mfc_write(struct file *file, const char __user *buffer,
  			size_t size, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	struct mfc_dma_command cmd;
  	int ret = -EINVAL;
  
  	if (size != sizeof cmd)
  		goto out;
  
  	ret = -EFAULT;
  	if (copy_from_user(&cmd, buffer, sizeof cmd))
  		goto out;
  
  	ret = spufs_check_valid_dma(&cmd);
  	if (ret)
  		goto out;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		goto out;
  
  	ret = spufs_wait(ctx->run_wq, ctx->state == SPU_STATE_RUNNABLE);
  	if (ret)
  		goto out;
  
  	if (file->f_flags & O_NONBLOCK) {
  		ret = ctx->ops->send_mfc_command(ctx, &cmd);
  	} else {
  		int status;
  		ret = spufs_wait(ctx->mfc_wq,
  				 spu_send_mfc_command(ctx, cmd, &status));
  		if (ret)
  			goto out;
  		if (status)
  			ret = status;
  	}
  
  	if (ret)
  		goto out_unlock;
  
  	ctx->tagwait |= 1 << cmd.tag;
  	ret = size;
  
  out_unlock:
  	spu_release(ctx);
  out:
  	return ret;
  }
  
  static unsigned int spufs_mfc_poll(struct file *file,poll_table *wait)
  {
  	struct spu_context *ctx = file->private_data;
  	u32 free_elements, tagstatus;
  	unsigned int mask;
  
  	poll_wait(file, &ctx->mfc_wq, wait);
  
  	/*
  	 * For now keep this uninterruptible and also ignore the rule
  	 * that poll should not sleep.  Will be fixed later.
  	 */
  	mutex_lock(&ctx->state_mutex);
  	ctx->ops->set_mfc_query(ctx, ctx->tagwait, 2);
  	free_elements = ctx->ops->get_mfc_free_elements(ctx);
  	tagstatus = ctx->ops->read_mfc_tagstatus(ctx);
  	spu_release(ctx);
  
  	mask = 0;
  	if (free_elements & 0xffff)
  		mask |= POLLOUT | POLLWRNORM;
  	if (tagstatus & ctx->tagwait)
  		mask |= POLLIN | POLLRDNORM;
  
  	pr_debug("%s: free %d tagstatus %d tagwait %d\n", __func__,
  		free_elements, tagstatus, ctx->tagwait);
  
  	return mask;
  }
  
  static int spufs_mfc_flush(struct file *file, fl_owner_t id)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		goto out;
  #if 0
  /* this currently hangs */
  	ret = spufs_wait(ctx->mfc_wq,
  			 ctx->ops->set_mfc_query(ctx, ctx->tagwait, 2));
  	if (ret)
  		goto out;
  	ret = spufs_wait(ctx->mfc_wq,
  			 ctx->ops->read_mfc_tagstatus(ctx) == ctx->tagwait);
  	if (ret)
  		goto out;
  #else
  	ret = 0;
  #endif
  	spu_release(ctx);
  out:
  	return ret;
  }
  
  static int spufs_mfc_fsync(struct file *file, loff_t start, loff_t end, int datasync)
  {
  	struct inode *inode = file_inode(file);
  	int err = filemap_write_and_wait_range(inode->i_mapping, start, end);
  	if (!err) {
  		inode_lock(inode);
  		err = spufs_mfc_flush(file, NULL);
  		inode_unlock(inode);
  	}
  	return err;
  }
  
  static int spufs_mfc_fasync(int fd, struct file *file, int on)
  {
  	struct spu_context *ctx = file->private_data;
  
  	return fasync_helper(fd, file, on, &ctx->mfc_fasync);
  }
  
  static const struct file_operations spufs_mfc_fops = {
  	.open	 = spufs_mfc_open,
  	.release = spufs_mfc_release,
  	.read	 = spufs_mfc_read,
  	.write	 = spufs_mfc_write,
  	.poll	 = spufs_mfc_poll,
  	.flush	 = spufs_mfc_flush,
  	.fsync	 = spufs_mfc_fsync,
  	.fasync	 = spufs_mfc_fasync,
  	.mmap	 = spufs_mfc_mmap,
  	.llseek  = no_llseek,
  };
  
  static int spufs_npc_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  	ctx->ops->npc_write(ctx, val);
  	spu_release(ctx);
  
  	return 0;
  }
  
  static u64 spufs_npc_get(struct spu_context *ctx)
  {
  	return ctx->ops->npc_read(ctx);
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_npc_ops, spufs_npc_get, spufs_npc_set,
  		       "0x%llx\n", SPU_ATTR_ACQUIRE);
  
  static int spufs_decr_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	int ret;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	lscsa->decr.slot[0] = (u32) val;
  	spu_release_saved(ctx);
  
  	return 0;
  }
  
  static u64 spufs_decr_get(struct spu_context *ctx)
  {
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	return lscsa->decr.slot[0];
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_decr_ops, spufs_decr_get, spufs_decr_set,
  		       "0x%llx\n", SPU_ATTR_ACQUIRE_SAVED);
  
  static int spufs_decr_status_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	int ret;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	if (val)
  		ctx->csa.priv2.mfc_control_RW |= MFC_CNTL_DECREMENTER_RUNNING;
  	else
  		ctx->csa.priv2.mfc_control_RW &= ~MFC_CNTL_DECREMENTER_RUNNING;
  	spu_release_saved(ctx);
  
  	return 0;
  }
  
  static u64 spufs_decr_status_get(struct spu_context *ctx)
  {
  	if (ctx->csa.priv2.mfc_control_RW & MFC_CNTL_DECREMENTER_RUNNING)
  		return SPU_DECR_STATUS_RUNNING;
  	else
  		return 0;
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_decr_status_ops, spufs_decr_status_get,
  		       spufs_decr_status_set, "0x%llx\n",
  		       SPU_ATTR_ACQUIRE_SAVED);
  
  static int spufs_event_mask_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	int ret;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	lscsa->event_mask.slot[0] = (u32) val;
  	spu_release_saved(ctx);
  
  	return 0;
  }
  
  static u64 spufs_event_mask_get(struct spu_context *ctx)
  {
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	return lscsa->event_mask.slot[0];
  }
  
  DEFINE_SPUFS_ATTRIBUTE(spufs_event_mask_ops, spufs_event_mask_get,
  		       spufs_event_mask_set, "0x%llx\n",
  		       SPU_ATTR_ACQUIRE_SAVED);
  
  static u64 spufs_event_status_get(struct spu_context *ctx)
  {
  	struct spu_state *state = &ctx->csa;
  	u64 stat;
  	stat = state->spu_chnlcnt_RW[0];
  	if (stat)
  		return state->spu_chnldata_RW[0];
  	return 0;
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_event_status_ops, spufs_event_status_get,
  		       NULL, "0x%llx\n", SPU_ATTR_ACQUIRE_SAVED)
  
  static int spufs_srr0_set(void *data, u64 val)
  {
  	struct spu_context *ctx = data;
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	int ret;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	lscsa->srr0.slot[0] = (u32) val;
  	spu_release_saved(ctx);
  
  	return 0;
  }
  
  static u64 spufs_srr0_get(struct spu_context *ctx)
  {
  	struct spu_lscsa *lscsa = ctx->csa.lscsa;
  	return lscsa->srr0.slot[0];
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_srr0_ops, spufs_srr0_get, spufs_srr0_set,
  		       "0x%llx\n", SPU_ATTR_ACQUIRE_SAVED)
  
  static u64 spufs_id_get(struct spu_context *ctx)
  {
  	u64 num;
  
  	if (ctx->state == SPU_STATE_RUNNABLE)
  		num = ctx->spu->number;
  	else
  		num = (unsigned int)-1;
  
  	return num;
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_id_ops, spufs_id_get, NULL, "0x%llx\n",
  		       SPU_ATTR_ACQUIRE)
  
  static u64 spufs_object_id_get(struct spu_context *ctx)
  {
  	/* FIXME: Should there really be no locking here? */
  	return ctx->object_id;
  }
  
  static int spufs_object_id_set(void *data, u64 id)
  {
  	struct spu_context *ctx = data;
  	ctx->object_id = id;
  
  	return 0;
  }
  
  DEFINE_SPUFS_ATTRIBUTE(spufs_object_id_ops, spufs_object_id_get,
  		       spufs_object_id_set, "0x%llx\n", SPU_ATTR_NOACQUIRE);
  
  static u64 spufs_lslr_get(struct spu_context *ctx)
  {
  	return ctx->csa.priv2.spu_lslr_RW;
  }
  DEFINE_SPUFS_ATTRIBUTE(spufs_lslr_ops, spufs_lslr_get, NULL, "0x%llx\n",
  		       SPU_ATTR_ACQUIRE_SAVED);
  
  static int spufs_info_open(struct inode *inode, struct file *file)
  {
  	struct spufs_inode_info *i = SPUFS_I(inode);
  	struct spu_context *ctx = i->i_ctx;
  	file->private_data = ctx;
  	return 0;
  }
  
  static int spufs_caps_show(struct seq_file *s, void *private)
  {
  	struct spu_context *ctx = s->private;
  
  	if (!(ctx->flags & SPU_CREATE_NOSCHED))
  		seq_puts(s, "sched\n");
  	if (!(ctx->flags & SPU_CREATE_ISOLATE))
  		seq_puts(s, "step\n");
  	return 0;
  }
  
  static int spufs_caps_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, spufs_caps_show, SPUFS_I(inode)->i_ctx);
  }
  
  static const struct file_operations spufs_caps_fops = {
  	.open		= spufs_caps_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= single_release,
  };
  
  static ssize_t __spufs_mbox_info_read(struct spu_context *ctx,
  			char __user *buf, size_t len, loff_t *pos)
  {
  	u32 data;
  
  	/* EOF if there's no entry in the mbox */
  	if (!(ctx->csa.prob.mb_stat_R & 0x0000ff))
  		return 0;
  
  	data = ctx->csa.prob.pu_mb_R;
  
  	return simple_read_from_buffer(buf, len, pos, &data, sizeof data);
  }
  
  static ssize_t spufs_mbox_info_read(struct file *file, char __user *buf,
  				   size_t len, loff_t *pos)
  {
  	int ret;
  	struct spu_context *ctx = file->private_data;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	spin_lock(&ctx->csa.register_lock);
  	ret = __spufs_mbox_info_read(ctx, buf, len, pos);
  	spin_unlock(&ctx->csa.register_lock);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static const struct file_operations spufs_mbox_info_fops = {
  	.open = spufs_info_open,
  	.read = spufs_mbox_info_read,
  	.llseek  = generic_file_llseek,
  };
  
  static ssize_t __spufs_ibox_info_read(struct spu_context *ctx,
  				char __user *buf, size_t len, loff_t *pos)
  {
  	u32 data;
  
  	/* EOF if there's no entry in the ibox */
  	if (!(ctx->csa.prob.mb_stat_R & 0xff0000))
  		return 0;
  
  	data = ctx->csa.priv2.puint_mb_R;
  
  	return simple_read_from_buffer(buf, len, pos, &data, sizeof data);
  }
  
  static ssize_t spufs_ibox_info_read(struct file *file, char __user *buf,
  				   size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	spin_lock(&ctx->csa.register_lock);
  	ret = __spufs_ibox_info_read(ctx, buf, len, pos);
  	spin_unlock(&ctx->csa.register_lock);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static const struct file_operations spufs_ibox_info_fops = {
  	.open = spufs_info_open,
  	.read = spufs_ibox_info_read,
  	.llseek  = generic_file_llseek,
  };
  
  static ssize_t __spufs_wbox_info_read(struct spu_context *ctx,
  			char __user *buf, size_t len, loff_t *pos)
  {
  	int i, cnt;
  	u32 data[4];
  	u32 wbox_stat;
  
  	wbox_stat = ctx->csa.prob.mb_stat_R;
  	cnt = 4 - ((wbox_stat & 0x00ff00) >> 8);
  	for (i = 0; i < cnt; i++) {
  		data[i] = ctx->csa.spu_mailbox_data[i];
  	}
  
  	return simple_read_from_buffer(buf, len, pos, &data,
  				cnt * sizeof(u32));
  }
  
  static ssize_t spufs_wbox_info_read(struct file *file, char __user *buf,
  				   size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	spin_lock(&ctx->csa.register_lock);
  	ret = __spufs_wbox_info_read(ctx, buf, len, pos);
  	spin_unlock(&ctx->csa.register_lock);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static const struct file_operations spufs_wbox_info_fops = {
  	.open = spufs_info_open,
  	.read = spufs_wbox_info_read,
  	.llseek  = generic_file_llseek,
  };
  
  static ssize_t __spufs_dma_info_read(struct spu_context *ctx,
  			char __user *buf, size_t len, loff_t *pos)
  {
  	struct spu_dma_info info;
  	struct mfc_cq_sr *qp, *spuqp;
  	int i;
  
  	info.dma_info_type = ctx->csa.priv2.spu_tag_status_query_RW;
  	info.dma_info_mask = ctx->csa.lscsa->tag_mask.slot[0];
  	info.dma_info_status = ctx->csa.spu_chnldata_RW[24];
  	info.dma_info_stall_and_notify = ctx->csa.spu_chnldata_RW[25];
  	info.dma_info_atomic_command_status = ctx->csa.spu_chnldata_RW[27];
  	for (i = 0; i < 16; i++) {
  		qp = &info.dma_info_command_data[i];
  		spuqp = &ctx->csa.priv2.spuq[i];
  
  		qp->mfc_cq_data0_RW = spuqp->mfc_cq_data0_RW;
  		qp->mfc_cq_data1_RW = spuqp->mfc_cq_data1_RW;
  		qp->mfc_cq_data2_RW = spuqp->mfc_cq_data2_RW;
  		qp->mfc_cq_data3_RW = spuqp->mfc_cq_data3_RW;
  	}
  
  	return simple_read_from_buffer(buf, len, pos, &info,
  				sizeof info);
  }
  
  static ssize_t spufs_dma_info_read(struct file *file, char __user *buf,
  			      size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	spin_lock(&ctx->csa.register_lock);
  	ret = __spufs_dma_info_read(ctx, buf, len, pos);
  	spin_unlock(&ctx->csa.register_lock);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static const struct file_operations spufs_dma_info_fops = {
  	.open = spufs_info_open,
  	.read = spufs_dma_info_read,
  	.llseek = no_llseek,
  };
  
  static ssize_t __spufs_proxydma_info_read(struct spu_context *ctx,
  			char __user *buf, size_t len, loff_t *pos)
  {
  	struct spu_proxydma_info info;
  	struct mfc_cq_sr *qp, *puqp;
  	int ret = sizeof info;
  	int i;
  
  	if (len < ret)
  		return -EINVAL;
  
  	if (!access_ok(VERIFY_WRITE, buf, len))
  		return -EFAULT;
  
  	info.proxydma_info_type = ctx->csa.prob.dma_querytype_RW;
  	info.proxydma_info_mask = ctx->csa.prob.dma_querymask_RW;
  	info.proxydma_info_status = ctx->csa.prob.dma_tagstatus_R;
  	for (i = 0; i < 8; i++) {
  		qp = &info.proxydma_info_command_data[i];
  		puqp = &ctx->csa.priv2.puq[i];
  
  		qp->mfc_cq_data0_RW = puqp->mfc_cq_data0_RW;
  		qp->mfc_cq_data1_RW = puqp->mfc_cq_data1_RW;
  		qp->mfc_cq_data2_RW = puqp->mfc_cq_data2_RW;
  		qp->mfc_cq_data3_RW = puqp->mfc_cq_data3_RW;
  	}
  
  	return simple_read_from_buffer(buf, len, pos, &info,
  				sizeof info);
  }
  
  static ssize_t spufs_proxydma_info_read(struct file *file, char __user *buf,
  				   size_t len, loff_t *pos)
  {
  	struct spu_context *ctx = file->private_data;
  	int ret;
  
  	ret = spu_acquire_saved(ctx);
  	if (ret)
  		return ret;
  	spin_lock(&ctx->csa.register_lock);
  	ret = __spufs_proxydma_info_read(ctx, buf, len, pos);
  	spin_unlock(&ctx->csa.register_lock);
  	spu_release_saved(ctx);
  
  	return ret;
  }
  
  static const struct file_operations spufs_proxydma_info_fops = {
  	.open = spufs_info_open,
  	.read = spufs_proxydma_info_read,
  	.llseek = no_llseek,
  };
  
  static int spufs_show_tid(struct seq_file *s, void *private)
  {
  	struct spu_context *ctx = s->private;
  
  	seq_printf(s, "%d\n", ctx->tid);
  	return 0;
  }
  
  static int spufs_tid_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, spufs_show_tid, SPUFS_I(inode)->i_ctx);
  }
  
  static const struct file_operations spufs_tid_fops = {
  	.open		= spufs_tid_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= single_release,
  };
  
  static const char *ctx_state_names[] = {
  	"user", "system", "iowait", "loaded"
  };
  
  static unsigned long long spufs_acct_time(struct spu_context *ctx,
  		enum spu_utilization_state state)
  {
  	unsigned long long time = ctx->stats.times[state];
  
  	/*
  	 * In general, utilization statistics are updated by the controlling
  	 * thread as the spu context moves through various well defined
  	 * state transitions, but if the context is lazily loaded its
  	 * utilization statistics are not updated as the controlling thread
  	 * is not tightly coupled with the execution of the spu context.  We
  	 * calculate and apply the time delta from the last recorded state
  	 * of the spu context.
  	 */
  	if (ctx->spu && ctx->stats.util_state == state) {
  		time += ktime_get_ns() - ctx->stats.tstamp;
  	}
  
  	return time / NSEC_PER_MSEC;
  }
  
  static unsigned long long spufs_slb_flts(struct spu_context *ctx)
  {
  	unsigned long long slb_flts = ctx->stats.slb_flt;
  
  	if (ctx->state == SPU_STATE_RUNNABLE) {
  		slb_flts += (ctx->spu->stats.slb_flt -
  			     ctx->stats.slb_flt_base);
  	}
  
  	return slb_flts;
  }
  
  static unsigned long long spufs_class2_intrs(struct spu_context *ctx)
  {
  	unsigned long long class2_intrs = ctx->stats.class2_intr;
  
  	if (ctx->state == SPU_STATE_RUNNABLE) {
  		class2_intrs += (ctx->spu->stats.class2_intr -
  				 ctx->stats.class2_intr_base);
  	}
  
  	return class2_intrs;
  }
  
  
  static int spufs_show_stat(struct seq_file *s, void *private)
  {
  	struct spu_context *ctx = s->private;
  	int ret;
  
  	ret = spu_acquire(ctx);
  	if (ret)
  		return ret;
  
  	seq_printf(s, "%s %llu %llu %llu %llu "
  		      "%llu %llu %llu %llu %llu %llu %llu %llu\n",
  		ctx_state_names[ctx->stats.util_state],
  		spufs_acct_time(ctx, SPU_UTIL_USER),
  		spufs_acct_time(ctx, SPU_UTIL_SYSTEM),
  		spufs_acct_time(ctx, SPU_UTIL_IOWAIT),
  		spufs_acct_time(ctx, SPU_UTIL_IDLE_LOADED),
  		ctx->stats.vol_ctx_switch,
  		ctx->stats.invol_ctx_switch,
  		spufs_slb_flts(ctx),
  		ctx->stats.hash_flt,
  		ctx->stats.min_flt,
  		ctx->stats.maj_flt,
  		spufs_class2_intrs(ctx),
  		ctx->stats.libassist);
  	spu_release(ctx);
  	return 0;
  }
  
  static int spufs_stat_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, spufs_show_stat, SPUFS_I(inode)->i_ctx);
  }
  
  static const struct file_operations spufs_stat_fops = {
  	.open		= spufs_stat_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= single_release,
  };
  
  static inline int spufs_switch_log_used(struct spu_context *ctx)
  {
  	return (ctx->switch_log->head - ctx->switch_log->tail) %
  		SWITCH_LOG_BUFSIZE;
  }
  
  static inline int spufs_switch_log_avail(struct spu_context *ctx)
  {
  	return SWITCH_LOG_BUFSIZE - spufs_switch_log_used(ctx);
  }
  
  static int spufs_switch_log_open(struct inode *inode, struct file *file)
  {
  	struct spu_context *ctx = SPUFS_I(inode)->i_ctx;
  	int rc;
  
  	rc = spu_acquire(ctx);
  	if (rc)
  		return rc;
  
  	if (ctx->switch_log) {
  		rc = -EBUSY;
  		goto out;
  	}
  
  	ctx->switch_log = kmalloc(sizeof(struct switch_log) +
  		SWITCH_LOG_BUFSIZE * sizeof(struct switch_log_entry),
  		GFP_KERNEL);
  
  	if (!ctx->switch_log) {
  		rc = -ENOMEM;
  		goto out;
  	}
  
  	ctx->switch_log->head = ctx->switch_log->tail = 0;
  	init_waitqueue_head(&ctx->switch_log->wait);
  	rc = 0;
  
  out:
  	spu_release(ctx);
  	return rc;
  }
  
  static int spufs_switch_log_release(struct inode *inode, struct file *file)
  {
  	struct spu_context *ctx = SPUFS_I(inode)->i_ctx;
  	int rc;
  
  	rc = spu_acquire(ctx);
  	if (rc)
  		return rc;
  
  	kfree(ctx->switch_log);
  	ctx->switch_log = NULL;
  	spu_release(ctx);
  
  	return 0;
  }
  
  static int switch_log_sprint(struct spu_context *ctx, char *tbuf, int n)
  {
  	struct switch_log_entry *p;
  
  	p = ctx->switch_log->log + ctx->switch_log->tail % SWITCH_LOG_BUFSIZE;
  
  	return snprintf(tbuf, n, "%u.%09u %d %u %u %llu\n",
  			(unsigned int) p->tstamp.tv_sec,
  			(unsigned int) p->tstamp.tv_nsec,
  			p->spu_id,
  			(unsigned int) p->type,
  			(unsigned int) p->val,
  			(unsigned long long) p->timebase);
  }
  
  static ssize_t spufs_switch_log_read(struct file *file, char __user *buf,
  			     size_t len, loff_t *ppos)
  {
  	struct inode *inode = file_inode(file);
  	struct spu_context *ctx = SPUFS_I(inode)->i_ctx;
  	int error = 0, cnt = 0;
  
  	if (!buf)
  		return -EINVAL;
  
  	error = spu_acquire(ctx);
  	if (error)
  		return error;
  
  	while (cnt < len) {
  		char tbuf[128];
  		int width;
  
  		if (spufs_switch_log_used(ctx) == 0) {
  			if (cnt > 0) {
  				/* If there's data ready to go, we can
  				 * just return straight away */
  				break;
  
  			} else if (file->f_flags & O_NONBLOCK) {
  				error = -EAGAIN;
  				break;
  
  			} else {
  				/* spufs_wait will drop the mutex and
  				 * re-acquire, but since we're in read(), the
  				 * file cannot be _released (and so
  				 * ctx->switch_log is stable).
  				 */
  				error = spufs_wait(ctx->switch_log->wait,
  						spufs_switch_log_used(ctx) > 0);
  
  				/* On error, spufs_wait returns without the
  				 * state mutex held */
  				if (error)
  					return error;
  
  				/* We may have had entries read from underneath
  				 * us while we dropped the mutex in spufs_wait,
  				 * so re-check */
  				if (spufs_switch_log_used(ctx) == 0)
  					continue;
  			}
  		}
  
  		width = switch_log_sprint(ctx, tbuf, sizeof(tbuf));
  		if (width < len)
  			ctx->switch_log->tail =
  				(ctx->switch_log->tail + 1) %
  				 SWITCH_LOG_BUFSIZE;
  		else
  			/* If the record is greater than space available return
  			 * partial buffer (so far) */
  			break;
  
  		error = copy_to_user(buf + cnt, tbuf, width);
  		if (error)
  			break;
  		cnt += width;
  	}
  
  	spu_release(ctx);
  
  	return cnt == 0 ? error : cnt;
  }
  
  static unsigned int spufs_switch_log_poll(struct file *file, poll_table *wait)
  {
  	struct inode *inode = file_inode(file);
  	struct spu_context *ctx = SPUFS_I(inode)->i_ctx;
  	unsigned int mask = 0;
  	int rc;
  
  	poll_wait(file, &ctx->switch_log->wait, wait);
  
  	rc = spu_acquire(ctx);
  	if (rc)
  		return rc;
  
  	if (spufs_switch_log_used(ctx) > 0)
  		mask |= POLLIN;
  
  	spu_release(ctx);
  
  	return mask;
  }
  
  static const struct file_operations spufs_switch_log_fops = {
  	.open		= spufs_switch_log_open,
  	.read		= spufs_switch_log_read,
  	.poll		= spufs_switch_log_poll,
  	.release	= spufs_switch_log_release,
  	.llseek		= no_llseek,
  };
  
  /**
   * Log a context switch event to a switch log reader.
   *
   * Must be called with ctx->state_mutex held.
   */
  void spu_switch_log_notify(struct spu *spu, struct spu_context *ctx,
  		u32 type, u32 val)
  {
  	if (!ctx->switch_log)
  		return;
  
  	if (spufs_switch_log_avail(ctx) > 1) {
  		struct switch_log_entry *p;
  
  		p = ctx->switch_log->log + ctx->switch_log->head;
  		ktime_get_ts(&p->tstamp);
  		p->timebase = get_tb();
  		p->spu_id = spu ? spu->number : -1;
  		p->type = type;
  		p->val = val;
  
  		ctx->switch_log->head =
  			(ctx->switch_log->head + 1) % SWITCH_LOG_BUFSIZE;
  	}
  
  	wake_up(&ctx->switch_log->wait);
  }
  
  static int spufs_show_ctx(struct seq_file *s, void *private)
  {
  	struct spu_context *ctx = s->private;
  	u64 mfc_control_RW;
  
  	mutex_lock(&ctx->state_mutex);
  	if (ctx->spu) {
  		struct spu *spu = ctx->spu;
  		struct spu_priv2 __iomem *priv2 = spu->priv2;
  
  		spin_lock_irq(&spu->register_lock);
  		mfc_control_RW = in_be64(&priv2->mfc_control_RW);
  		spin_unlock_irq(&spu->register_lock);
  	} else {
  		struct spu_state *csa = &ctx->csa;
  
  		mfc_control_RW = csa->priv2.mfc_control_RW;
  	}
  
  	seq_printf(s, "%c flgs(%lx) sflgs(%lx) pri(%d) ts(%d) spu(%02d)"
  		" %c %llx %llx %llx %llx %x %x\n",
  		ctx->state == SPU_STATE_SAVED ? 'S' : 'R',
  		ctx->flags,
  		ctx->sched_flags,
  		ctx->prio,
  		ctx->time_slice,
  		ctx->spu ? ctx->spu->number : -1,
  		!list_empty(&ctx->rq) ? 'q' : ' ',
  		ctx->csa.class_0_pending,
  		ctx->csa.class_0_dar,
  		ctx->csa.class_1_dsisr,
  		mfc_control_RW,
  		ctx->ops->runcntl_read(ctx),
  		ctx->ops->status_read(ctx));
  
  	mutex_unlock(&ctx->state_mutex);
  
  	return 0;
  }
  
  static int spufs_ctx_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, spufs_show_ctx, SPUFS_I(inode)->i_ctx);
  }
  
  static const struct file_operations spufs_ctx_fops = {
  	.open           = spufs_ctx_open,
  	.read           = seq_read,
  	.llseek         = seq_lseek,
  	.release        = single_release,
  };
  
  const struct spufs_tree_descr spufs_dir_contents[] = {
  	{ "capabilities", &spufs_caps_fops, 0444, },
  	{ "mem",  &spufs_mem_fops,  0666, LS_SIZE, },
  	{ "regs", &spufs_regs_fops,  0666, sizeof(struct spu_reg128[128]), },
  	{ "mbox", &spufs_mbox_fops, 0444, },
  	{ "ibox", &spufs_ibox_fops, 0444, },
  	{ "wbox", &spufs_wbox_fops, 0222, },
  	{ "mbox_stat", &spufs_mbox_stat_fops, 0444, sizeof(u32), },
  	{ "ibox_stat", &spufs_ibox_stat_fops, 0444, sizeof(u32), },
  	{ "wbox_stat", &spufs_wbox_stat_fops, 0444, sizeof(u32), },
  	{ "signal1", &spufs_signal1_fops, 0666, },
  	{ "signal2", &spufs_signal2_fops, 0666, },
  	{ "signal1_type", &spufs_signal1_type, 0666, },
  	{ "signal2_type", &spufs_signal2_type, 0666, },
  	{ "cntl", &spufs_cntl_fops,  0666, },
  	{ "fpcr", &spufs_fpcr_fops, 0666, sizeof(struct spu_reg128), },
  	{ "lslr", &spufs_lslr_ops, 0444, },
  	{ "mfc", &spufs_mfc_fops, 0666, },
  	{ "mss", &spufs_mss_fops, 0666, },
  	{ "npc", &spufs_npc_ops, 0666, },
  	{ "srr0", &spufs_srr0_ops, 0666, },
  	{ "decr", &spufs_decr_ops, 0666, },
  	{ "decr_status", &spufs_decr_status_ops, 0666, },
  	{ "event_mask", &spufs_event_mask_ops, 0666, },
  	{ "event_status", &spufs_event_status_ops, 0444, },
  	{ "psmap", &spufs_psmap_fops, 0666, SPUFS_PS_MAP_SIZE, },
  	{ "phys-id", &spufs_id_ops, 0666, },
  	{ "object-id", &spufs_object_id_ops, 0666, },
  	{ "mbox_info", &spufs_mbox_info_fops, 0444, sizeof(u32), },
  	{ "ibox_info", &spufs_ibox_info_fops, 0444, sizeof(u32), },
  	{ "wbox_info", &spufs_wbox_info_fops, 0444, sizeof(u32), },
  	{ "dma_info", &spufs_dma_info_fops, 0444,
  		sizeof(struct spu_dma_info), },
  	{ "proxydma_info", &spufs_proxydma_info_fops, 0444,
  		sizeof(struct spu_proxydma_info)},
  	{ "tid", &spufs_tid_fops, 0444, },
  	{ "stat", &spufs_stat_fops, 0444, },
  	{ "switch_log", &spufs_switch_log_fops, 0444 },
  	{},
  };
  
  const struct spufs_tree_descr spufs_dir_nosched_contents[] = {
  	{ "capabilities", &spufs_caps_fops, 0444, },
  	{ "mem",  &spufs_mem_fops,  0666, LS_SIZE, },
  	{ "mbox", &spufs_mbox_fops, 0444, },
  	{ "ibox", &spufs_ibox_fops, 0444, },
  	{ "wbox", &spufs_wbox_fops, 0222, },
  	{ "mbox_stat", &spufs_mbox_stat_fops, 0444, sizeof(u32), },
  	{ "ibox_stat", &spufs_ibox_stat_fops, 0444, sizeof(u32), },
  	{ "wbox_stat", &spufs_wbox_stat_fops, 0444, sizeof(u32), },
  	{ "signal1", &spufs_signal1_nosched_fops, 0222, },
  	{ "signal2", &spufs_signal2_nosched_fops, 0222, },
  	{ "signal1_type", &spufs_signal1_type, 0666, },
  	{ "signal2_type", &spufs_signal2_type, 0666, },
  	{ "mss", &spufs_mss_fops, 0666, },
  	{ "mfc", &spufs_mfc_fops, 0666, },
  	{ "cntl", &spufs_cntl_fops,  0666, },
  	{ "npc", &spufs_npc_ops, 0666, },
  	{ "psmap", &spufs_psmap_fops, 0666, SPUFS_PS_MAP_SIZE, },
  	{ "phys-id", &spufs_id_ops, 0666, },
  	{ "object-id", &spufs_object_id_ops, 0666, },
  	{ "tid", &spufs_tid_fops, 0444, },
  	{ "stat", &spufs_stat_fops, 0444, },
  	{},
  };
  
  const struct spufs_tree_descr spufs_dir_debug_contents[] = {
  	{ ".ctx", &spufs_ctx_fops, 0444, },
  	{},
  };
  
  const struct spufs_coredump_reader spufs_coredump_read[] = {
  	{ "regs", __spufs_regs_read, NULL, sizeof(struct spu_reg128[128])},
  	{ "fpcr", __spufs_fpcr_read, NULL, sizeof(struct spu_reg128) },
  	{ "lslr", NULL, spufs_lslr_get, 19 },
  	{ "decr", NULL, spufs_decr_get, 19 },
  	{ "decr_status", NULL, spufs_decr_status_get, 19 },
  	{ "mem", __spufs_mem_read, NULL, LS_SIZE, },
  	{ "signal1", __spufs_signal1_read, NULL, sizeof(u32) },
  	{ "signal1_type", NULL, spufs_signal1_type_get, 19 },
  	{ "signal2", __spufs_signal2_read, NULL, sizeof(u32) },
  	{ "signal2_type", NULL, spufs_signal2_type_get, 19 },
  	{ "event_mask", NULL, spufs_event_mask_get, 19 },
  	{ "event_status", NULL, spufs_event_status_get, 19 },
  	{ "mbox_info", __spufs_mbox_info_read, NULL, sizeof(u32) },
  	{ "ibox_info", __spufs_ibox_info_read, NULL, sizeof(u32) },
  	{ "wbox_info", __spufs_wbox_info_read, NULL, 4 * sizeof(u32)},
  	{ "dma_info", __spufs_dma_info_read, NULL, sizeof(struct spu_dma_info)},
  	{ "proxydma_info", __spufs_proxydma_info_read,
  			   NULL, sizeof(struct spu_proxydma_info)},
  	{ "object-id", NULL, spufs_object_id_get, 19 },
  	{ "npc", NULL, spufs_npc_get, 19 },
  	{ NULL },
  };
  