1 files changed, 167 insertions, 120 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index 010a51f5979..90986923a53 100644
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -24,12 +24,12 @@
 
 #include <linux/fs.h>
 #include <linux/ioctl.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/pagemap.h>
 #include <linux/poll.h>
 #include <linux/ptrace.h>
 #include <linux/seq_file.h>
-#include <linux/marker.h>
+#include <linux/slab.h>
 
 #include <asm/io.h>
 #include <asm/time.h>
@@ -38,6 +38,7 @@
 #include <asm/uaccess.h>
 
 #include "spufs.h"
+#include "sputrace.h"
 
 #define SPUFS_MMAP_4K (PAGE_SIZE == 0x1000)
 
@@ -147,12 +148,12 @@ 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 struct file_operations __fops = {				\
-	.owner	 = THIS_MODULE,						\
+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,					\
 };
 
 
@@ -217,24 +218,17 @@ spufs_mem_write(struct file *file, const char __user *buffer,
 	loff_t pos = *ppos;
 	int ret;
 
-	if (pos < 0)
-		return -EINVAL;
 	if (pos > LS_SIZE)
 		return -EFBIG;
-	if (size > LS_SIZE - pos)
-		size = LS_SIZE - pos;
 
 	ret = spu_acquire(ctx);
 	if (ret)
 		return ret;
 
 	local_store = ctx->ops->get_ls(ctx);
-	ret = copy_from_user(local_store + pos, buffer, size);
+	size = simple_write_to_buffer(local_store, LS_SIZE, ppos, buffer, size);
 	spu_release(ctx);
 
-	if (ret)
-		return -EFAULT;
-	*ppos = pos + size;
 	return size;
 }
 
@@ -273,12 +267,10 @@ spufs_mem_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 		return VM_FAULT_NOPAGE;
 
 	if (ctx->state == SPU_STATE_SAVED) {
-		vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-							& ~_PAGE_NO_CACHE);
+		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(pgprot_val(vma->vm_page_prot)
-					     | _PAGE_NO_CACHE);
+		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);
@@ -311,7 +303,7 @@ static int spufs_mem_mmap_access(struct vm_area_struct *vma,
 	return len;
 }
 
-static struct vm_operations_struct spufs_mem_mmap_vmops = {
+static const struct vm_operations_struct spufs_mem_mmap_vmops = {
 	.fault = spufs_mem_mmap_fault,
 	.access = spufs_mem_mmap_access,
 };
@@ -338,8 +330,7 @@ static int spufs_mem_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE);
+	vma->vm_page_prot = pgprot_noncached_wc(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_mem_mmap_vmops;
 	return 0;
@@ -360,7 +351,7 @@ static unsigned long spufs_get_unmapped_area(struct file *file,
 
 	/* Else, try to obtain a 64K pages slice */
 	return slice_get_unmapped_area(addr, len, flags,
-				       MMU_PAGE_64K, 1, 0);
+				       MMU_PAGE_64K, 1);
 }
 #endif /* CONFIG_SPU_FS_64K_LS */
 
@@ -390,6 +381,9 @@ static int spufs_ps_fault(struct vm_area_struct *vma,
 	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
@@ -436,7 +430,7 @@ static int spufs_cntl_mmap_fault(struct vm_area_struct *vma,
 	return spufs_ps_fault(vma, vmf, 0x4000, SPUFS_CNTL_MAP_SIZE);
 }
 
-static struct vm_operations_struct spufs_cntl_mmap_vmops = {
+static const struct vm_operations_struct spufs_cntl_mmap_vmops = {
 	.fault = spufs_cntl_mmap_fault,
 };
 
@@ -449,8 +443,7 @@ static int spufs_cntl_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE | _PAGE_GUARDED);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_cntl_mmap_vmops;
 	return 0;
@@ -521,6 +514,7 @@ static const struct file_operations spufs_cntl_fops = {
 	.release = spufs_cntl_release,
 	.read = simple_attr_read,
 	.write = simple_attr_write,
+	.llseek	= generic_file_llseek,
 	.mmap = spufs_cntl_mmap,
 };
 
@@ -548,6 +542,11 @@ spufs_regs_read(struct file *file, char __user *buffer,
 	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;
@@ -564,20 +563,18 @@ spufs_regs_write(struct file *file, const char __user *buffer,
 	struct spu_lscsa *lscsa = ctx->csa.lscsa;
 	int ret;
 
-	size = min_t(ssize_t, sizeof lscsa->gprs - *pos, size);
-	if (size <= 0)
+	if (*pos >= sizeof(lscsa->gprs))
 		return -EFBIG;
-	*pos += size;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
 
-	ret = copy_from_user(lscsa->gprs + *pos - size,
-			     buffer, size) ? -EFAULT : size;
+	size = simple_write_to_buffer(lscsa->gprs, sizeof(lscsa->gprs), pos,
+					buffer, size);
 
 	spu_release_saved(ctx);
-	return ret;
+	return size;
 }
 
 static const struct file_operations spufs_regs_fops = {
@@ -619,20 +616,18 @@ spufs_fpcr_write(struct file *file, const char __user * buffer,
 	struct spu_lscsa *lscsa = ctx->csa.lscsa;
 	int ret;
 
-	size = min_t(ssize_t, sizeof(lscsa->fpcr) - *pos, size);
-	if (size <= 0)
+	if (*pos >= sizeof(lscsa->fpcr))
 		return -EFBIG;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
 
-	*pos += size;
-	ret = copy_from_user((char *)&lscsa->fpcr + *pos - size,
-			     buffer, size) ? -EFAULT : size;
+	size = simple_write_to_buffer(&lscsa->fpcr, sizeof(lscsa->fpcr), pos,
+					buffer, size);
 
 	spu_release_saved(ctx);
-	return ret;
+	return size;
 }
 
 static const struct file_operations spufs_fpcr_fops = {
@@ -707,6 +702,7 @@ static ssize_t spufs_mbox_read(struct file *file, char __user *buf,
 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,
@@ -736,6 +732,7 @@ static ssize_t spufs_mbox_stat_read(struct file *file, char __user *buf,
 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 */
@@ -856,6 +853,7 @@ static const struct file_operations spufs_ibox_fops = {
 	.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,
@@ -883,6 +881,7 @@ static ssize_t spufs_ibox_stat_read(struct file *file, char __user *buf,
 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 */
@@ -1004,6 +1003,7 @@ static const struct file_operations spufs_wbox_fops = {
 	.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,
@@ -1031,6 +1031,7 @@ static ssize_t spufs_wbox_stat_read(struct file *file, char __user *buf,
 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)
@@ -1137,7 +1138,7 @@ spufs_signal1_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 #endif
 }
 
-static struct vm_operations_struct spufs_signal1_mmap_vmops = {
+static const struct vm_operations_struct spufs_signal1_mmap_vmops = {
 	.fault = spufs_signal1_mmap_fault,
 };
 
@@ -1147,8 +1148,7 @@ static int spufs_signal1_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE | _PAGE_GUARDED);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_signal1_mmap_vmops;
 	return 0;
@@ -1160,6 +1160,7 @@ static const struct file_operations spufs_signal1_fops = {
 	.read = spufs_signal1_read,
 	.write = spufs_signal1_write,
 	.mmap = spufs_signal1_mmap,
+	.llseek = no_llseek,
 };
 
 static const struct file_operations spufs_signal1_nosched_fops = {
@@ -1167,6 +1168,7 @@ static const struct file_operations spufs_signal1_nosched_fops = {
 	.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)
@@ -1274,7 +1276,7 @@ spufs_signal2_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 #endif
 }
 
-static struct vm_operations_struct spufs_signal2_mmap_vmops = {
+static const struct vm_operations_struct spufs_signal2_mmap_vmops = {
 	.fault = spufs_signal2_mmap_fault,
 };
 
@@ -1284,8 +1286,7 @@ static int spufs_signal2_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE | _PAGE_GUARDED);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_signal2_mmap_vmops;
 	return 0;
@@ -1300,6 +1301,7 @@ static const struct file_operations spufs_signal2_fops = {
 	.read = spufs_signal2_read,
 	.write = spufs_signal2_write,
 	.mmap = spufs_signal2_mmap,
+	.llseek = no_llseek,
 };
 
 static const struct file_operations spufs_signal2_nosched_fops = {
@@ -1307,6 +1309,7 @@ static const struct file_operations spufs_signal2_nosched_fops = {
 	.release = spufs_signal2_release,
 	.write = spufs_signal2_write,
 	.mmap = spufs_signal2_mmap,
+	.llseek = no_llseek,
 };
 
 /*
@@ -1393,7 +1396,7 @@ 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 struct vm_operations_struct spufs_mss_mmap_vmops = {
+static const struct vm_operations_struct spufs_mss_mmap_vmops = {
 	.fault = spufs_mss_mmap_fault,
 };
 
@@ -1406,8 +1409,7 @@ static int spufs_mss_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE | _PAGE_GUARDED);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_mss_mmap_vmops;
 	return 0;
@@ -1447,6 +1449,7 @@ 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
@@ -1455,7 +1458,7 @@ 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 struct vm_operations_struct spufs_psmap_mmap_vmops = {
+static const struct vm_operations_struct spufs_psmap_mmap_vmops = {
 	.fault = spufs_psmap_mmap_fault,
 };
 
@@ -1468,8 +1471,7 @@ static int spufs_psmap_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE | _PAGE_GUARDED);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_psmap_mmap_vmops;
 	return 0;
@@ -1505,6 +1507,7 @@ static const struct file_operations spufs_psmap_fops = {
 	.open	 = spufs_psmap_open,
 	.release = spufs_psmap_release,
 	.mmap	 = spufs_psmap_mmap,
+	.llseek  = no_llseek,
 };
 
 
@@ -1515,7 +1518,7 @@ 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 struct vm_operations_struct spufs_mfc_mmap_vmops = {
+static const struct vm_operations_struct spufs_mfc_mmap_vmops = {
 	.fault = spufs_mfc_mmap_fault,
 };
 
@@ -1528,8 +1531,7 @@ static int spufs_mfc_mmap(struct file *file, struct vm_area_struct *vma)
 		return -EINVAL;
 
 	vma->vm_flags |= VM_IO | VM_PFNMAP;
-	vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
-				     | _PAGE_NO_CACHE | _PAGE_GUARDED);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	vma->vm_ops = &spufs_mfc_mmap_vmops;
 	return 0;
@@ -1655,7 +1657,7 @@ out:
 
 static int spufs_check_valid_dma(struct mfc_dma_command *cmd)
 {
-	pr_debug("queueing DMA %x %lx %x %x %x\n", cmd->lsa,
+	pr_debug("queueing DMA %x %llx %x %x %x\n", cmd->lsa,
 		 cmd->ea, cmd->size, cmd->tag, cmd->cmd);
 
 	switch (cmd->cmd) {
@@ -1672,7 +1674,7 @@ static int spufs_check_valid_dma(struct mfc_dma_command *cmd)
 	}
 
 	if ((cmd->lsa & 0xf) != (cmd->ea &0xf)) {
-		pr_debug("invalid DMA alignment, ea %lx lsa %x\n",
+		pr_debug("invalid DMA alignment, ea %llx lsa %x\n",
 				cmd->ea, cmd->lsa);
 		return -EIO;
 	}
@@ -1847,10 +1849,16 @@ out:
 	return ret;
 }
 
-static int spufs_mfc_fsync(struct file *file, struct dentry *dentry,
-			   int datasync)
+static int spufs_mfc_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 {
-	return spufs_mfc_flush(file, NULL);
+	struct inode *inode = file_inode(file);
+	int err = filemap_write_and_wait_range(inode->i_mapping, start, end);
+	if (!err) {
+		mutex_lock(&inode->i_mutex);
+		err = spufs_mfc_flush(file, NULL);
+		mutex_unlock(&inode->i_mutex);
+	}
+	return err;
 }
 
 static int spufs_mfc_fasync(int fd, struct file *file, int on)
@@ -1870,6 +1878,7 @@ static const struct file_operations spufs_mfc_fops = {
 	.fsync	 = spufs_mfc_fsync,
 	.fasync	 = spufs_mfc_fasync,
 	.mmap	 = spufs_mfc_mmap,
+	.llseek  = no_llseek,
 };
 
 static int spufs_npc_set(void *data, u64 val)
@@ -2245,6 +2254,7 @@ static ssize_t spufs_dma_info_read(struct file *file, char __user *buf,
 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,
@@ -2298,6 +2308,7 @@ static ssize_t spufs_proxydma_info_read(struct file *file, char __user *buf,
 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)
@@ -2426,38 +2437,49 @@ static inline int spufs_switch_log_avail(struct spu_context *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;
 
-	/*
-	 * We (ab-)use the mapping_lock here because it serves the similar
-	 * purpose for synchronizing open/close elsewhere.  Maybe it should
-	 * be renamed eventually.
-	 */
-	mutex_lock(&ctx->mapping_lock);
 	if (ctx->switch_log) {
-		spin_lock(&ctx->switch_log->lock);
-		ctx->switch_log->head = 0;
-		ctx->switch_log->tail = 0;
-		spin_unlock(&ctx->switch_log->lock);
-	} else {
-		/*
-		 * We allocate the switch log data structures on first open.
-		 * They will never be free because we assume a context will
-		 * be traced until it goes away.
-		 */
-		ctx->switch_log = kzalloc(sizeof(struct switch_log) +
-			SWITCH_LOG_BUFSIZE * sizeof(struct switch_log_entry),
-			GFP_KERNEL);
-		if (!ctx->switch_log)
-			goto out;
-		spin_lock_init(&ctx->switch_log->lock);
-		init_waitqueue_head(&ctx->switch_log->wait);
+		rc = -EBUSY;
+		goto out;
 	}
-	mutex_unlock(&ctx->mapping_lock);
+
+	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;
- out:
-	mutex_unlock(&ctx->mapping_lock);
-	return -ENOMEM;
 }
 
 static int switch_log_sprint(struct spu_context *ctx, char *tbuf, int n)
@@ -2478,49 +2500,61 @@ static int switch_log_sprint(struct spu_context *ctx, char *tbuf, int n)
 static ssize_t spufs_switch_log_read(struct file *file, char __user *buf,
 			     size_t len, loff_t *ppos)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct spu_context *ctx = SPUFS_I(inode)->i_ctx;
 	int error = 0, cnt = 0;
 
-	if (!buf || len < 0)
+	if (!buf)
 		return -EINVAL;
 
+	error = spu_acquire(ctx);
+	if (error)
+		return error;
+
 	while (cnt < len) {
 		char tbuf[128];
 		int width;
 
-		if (file->f_flags & O_NONBLOCK) {
-			if (spufs_switch_log_used(ctx) <= 0)
-				return cnt ? cnt : -EAGAIN;
-		} else {
-			/* Wait for data in buffer */
-			error = wait_event_interruptible(ctx->switch_log->wait,
-					spufs_switch_log_used(ctx) > 0);
-			if (error)
+		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;
-		}
 
-		spin_lock(&ctx->switch_log->lock);
-		if (ctx->switch_log->head == ctx->switch_log->tail) {
-			/* multiple readers race? */
-			spin_unlock(&ctx->switch_log->lock);
-			continue;
+			} 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) {
+		if (width < len)
 			ctx->switch_log->tail =
 				(ctx->switch_log->tail + 1) %
 				 SWITCH_LOG_BUFSIZE;
-		}
-
-		spin_unlock(&ctx->switch_log->lock);
-
-		/*
-		 * If the record is greater than space available return
-		 * partial buffer (so far)
-		 */
-		if (width >= len)
+		else
+			/* If the record is greater than space available return
+			 * partial buffer (so far) */
 			break;
 
 		error = copy_to_user(buf + cnt, tbuf, width);
@@ -2529,37 +2563,51 @@ static ssize_t spufs_switch_log_read(struct file *file, char __user *buf,
 		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->f_path.dentry->d_inode;
+	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 = {
-	.owner	= THIS_MODULE,
-	.open	= spufs_switch_log_open,
-	.read	= spufs_switch_log_read,
-	.poll	= spufs_switch_log_poll,
+	.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;
 
-	spin_lock(&ctx->switch_log->lock);
 	if (spufs_switch_log_avail(ctx) > 1) {
 		struct switch_log_entry *p;
 
@@ -2573,7 +2621,6 @@ void spu_switch_log_notify(struct spu *spu, struct spu_context *ctx,
 		ctx->switch_log->head =
 			(ctx->switch_log->head + 1) % SWITCH_LOG_BUFSIZE;
 	}
-	spin_unlock(&ctx->switch_log->lock);
 
 	wake_up(&ctx->switch_log->wait);
 }
@@ -2598,7 +2645,7 @@ static int spufs_show_ctx(struct seq_file *s, void *private)
 	}
 
 	seq_printf(s, "%c flgs(%lx) sflgs(%lx) pri(%d) ts(%d) spu(%02d)"
-		" %c %lx %lx %lx %lx %x %x\n",
+		" %c %llx %llx %llx %llx %x %x\n",
 		ctx->state == SPU_STATE_SAVED ? 'S' : 'R',
 		ctx->flags,
 		ctx->sched_flags,
@@ -2630,7 +2677,7 @@ static const struct file_operations spufs_ctx_fops = {
 	.release        = single_release,
 };
 
-struct spufs_tree_descr spufs_dir_contents[] = {
+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]), },
@@ -2671,7 +2718,7 @@ struct spufs_tree_descr spufs_dir_contents[] = {
 	{},
 };
 
-struct spufs_tree_descr spufs_dir_nosched_contents[] = {
+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, },
@@ -2696,12 +2743,12 @@ struct spufs_tree_descr spufs_dir_nosched_contents[] = {
 	{},
 };
 
-struct spufs_tree_descr spufs_dir_debug_contents[] = {
+const struct spufs_tree_descr spufs_dir_debug_contents[] = {
 	{ ".ctx", &spufs_ctx_fops, 0444, },
 	{},
 };
 
-struct spufs_coredump_reader spufs_coredump_read[] = {
+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 },