[POWERPC] spufs: add enchanced simple attr macros

The simple attr macros currently used by spufs can't deal with the
handlers returning errors, which is required to make the state_mutex
interruptible.  This adds a local copy that allows for an error
return from the get/set handlers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 154 insertions, 24 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index 78df905743b3..510adc57af90 100644
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -40,6 +40,120 @@
 
 #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 struct file_operations __fops = {                                \
+        .owner   = THIS_MODULE,                                         \
+        .open    = __fops ## _open,                                     \
+        .release = spufs_attr_release,                                  \
+        .read    = spufs_attr_read,                                     \
+        .write   = spufs_attr_write,                                    \
+};
+
 
 static int
 spufs_mem_open(struct inode *inode, struct file *file)
@@ -296,25 +410,26 @@ static int spufs_cntl_mmap(struct file *file, struct vm_area_struct *vma)
 #define spufs_cntl_mmap NULL
 #endif /* !SPUFS_MMAP_4K */
 
-static u64 spufs_cntl_get(void *data)
+static int spufs_cntl_get(void *data, u64 *val)
 {
         struct spu_context *ctx = data;
-        u64 val;
 
         spu_acquire(ctx);
-        val = ctx->ops->status_read(ctx);
+        *val = ctx->ops->status_read(ctx);
         spu_release(ctx);
 
-        return val;
+        return 0;
 }
 
-static void spufs_cntl_set(void *data, u64 val)
+static int spufs_cntl_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
 
         spu_acquire(ctx);
         ctx->ops->runcntl_write(ctx, val);
         spu_release(ctx);
+
+        return 0;
 }
 
 static int spufs_cntl_open(struct inode *inode, struct file *file)
@@ -327,7 +442,7 @@ static int spufs_cntl_open(struct inode *inode, struct file *file)
         if (!i->i_openers++)
                 ctx->cntl = inode->i_mapping;
         mutex_unlock(&ctx->mapping_lock);
-        return simple_attr_open(inode, file, spufs_cntl_get,
+        return spufs_attr_open(inode, file, spufs_cntl_get,
                                         spufs_cntl_set, "0x%08lx");
 }
 
@@ -337,7 +452,7 @@ 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_close(inode, file);
+        spufs_attr_release(inode, file);
 
         mutex_lock(&ctx->mapping_lock);
         if (!--i->i_openers)
@@ -349,8 +464,8 @@ spufs_cntl_release(struct inode *inode, struct file *file)
 static const struct file_operations spufs_cntl_fops = {
         .open = spufs_cntl_open,
         .release = spufs_cntl_release,
-        .read = simple_attr_read,
-        .write = simple_attr_write,
+        .read = spufs_attr_read,
+        .write = spufs_attr_write,
         .mmap = spufs_cntl_mmap,
 };
 
@@ -1102,33 +1217,34 @@ static const struct file_operations spufs_signal2_nosched_fops = {
 #define SPU_ATTR_ACQUIRE_SAVED  2
 
 #define DEFINE_SPUFS_ATTRIBUTE(__name, __get, __set, __fmt, __acquire)  \
-static u64 __##__get(void *data)                                        \
+static int __##__get(void *data, u64 *val)                              \
 {                                                                       \
         struct spu_context *ctx = data;                                 \
-        u64 ret;                                                        \
                                                                         \
         if (__acquire == SPU_ATTR_ACQUIRE) {                            \
                 spu_acquire(ctx);                                       \
-                ret = __get(ctx);                                       \
+                *val = __get(ctx);                                      \
                 spu_release(ctx);                                       \
         } else if (__acquire == SPU_ATTR_ACQUIRE_SAVED) {               \
                 spu_acquire_saved(ctx);                                 \
-                ret = __get(ctx);                                       \
+                *val = __get(ctx);                                      \
                 spu_release_saved(ctx);                                 \
         } else                                                          \
-                ret = __get(ctx);                                       \
+                *val = __get(ctx);                                      \
                                                                         \
-        return ret;                                                     \
+        return 0;                                                       \
 }                                                                       \
-DEFINE_SIMPLE_ATTRIBUTE(__name, __##__get, __set, __fmt);
+DEFINE_SPUFS_SIMPLE_ATTRIBUTE(__name, __##__get, __set, __fmt);
 
-static void spufs_signal1_type_set(void *data, u64 val)
+static int spufs_signal1_type_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
 
         spu_acquire(ctx);
         ctx->ops->signal1_type_set(ctx, val);
         spu_release(ctx);
+
+        return 0;
 }
 
 static u64 spufs_signal1_type_get(struct spu_context *ctx)
@@ -1139,13 +1255,15 @@ DEFINE_SPUFS_ATTRIBUTE(spufs_signal1_type, spufs_signal1_type_get,
                        spufs_signal1_type_set, "%llu", SPU_ATTR_ACQUIRE);
 
 
-static void spufs_signal2_type_set(void *data, u64 val)
+static int spufs_signal2_type_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
 
         spu_acquire(ctx);
         ctx->ops->signal2_type_set(ctx, val);
         spu_release(ctx);
+
+        return 0;
 }
 
 static u64 spufs_signal2_type_get(struct spu_context *ctx)
@@ -1625,12 +1743,14 @@ static const struct file_operations spufs_mfc_fops = {
         .mmap    = spufs_mfc_mmap,
 };
 
-static void spufs_npc_set(void *data, u64 val)
+static int spufs_npc_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
         spu_acquire(ctx);
         ctx->ops->npc_write(ctx, val);
         spu_release(ctx);
+
+        return 0;
 }
 
 static u64 spufs_npc_get(struct spu_context *ctx)
@@ -1640,13 +1760,15 @@ static u64 spufs_npc_get(struct spu_context *ctx)
 DEFINE_SPUFS_ATTRIBUTE(spufs_npc_ops, spufs_npc_get, spufs_npc_set,
                        "0x%llx\n", SPU_ATTR_ACQUIRE);
 
-static void spufs_decr_set(void *data, u64 val)
+static int spufs_decr_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
         struct spu_lscsa *lscsa = ctx->csa.lscsa;
         spu_acquire_saved(ctx);
         lscsa->decr.slot[0] = (u32) val;
         spu_release_saved(ctx);
+
+        return 0;
 }
 
 static u64 spufs_decr_get(struct spu_context *ctx)
@@ -1657,7 +1779,7 @@ static u64 spufs_decr_get(struct spu_context *ctx)
 DEFINE_SPUFS_ATTRIBUTE(spufs_decr_ops, spufs_decr_get, spufs_decr_set,
                        "0x%llx\n", SPU_ATTR_ACQUIRE_SAVED);
 
-static void spufs_decr_status_set(void *data, u64 val)
+static int spufs_decr_status_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
         spu_acquire_saved(ctx);
@@ -1666,6 +1788,8 @@ static void spufs_decr_status_set(void *data, u64 val)
         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)
@@ -1679,13 +1803,15 @@ DEFINE_SPUFS_ATTRIBUTE(spufs_decr_status_ops, spufs_decr_status_get,
                        spufs_decr_status_set, "0x%llx\n",
                        SPU_ATTR_ACQUIRE_SAVED);
 
-static void spufs_event_mask_set(void *data, u64 val)
+static int spufs_event_mask_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
         struct spu_lscsa *lscsa = ctx->csa.lscsa;
         spu_acquire_saved(ctx);
         lscsa->event_mask.slot[0] = (u32) val;
         spu_release_saved(ctx);
+
+        return 0;
 }
 
 static u64 spufs_event_mask_get(struct spu_context *ctx)
@@ -1710,13 +1836,15 @@ static u64 spufs_event_status_get(struct spu_context *ctx)
 DEFINE_SPUFS_ATTRIBUTE(spufs_event_status_ops, spufs_event_status_get,
                        NULL, "0x%llx\n", SPU_ATTR_ACQUIRE_SAVED)
 
-static void spufs_srr0_set(void *data, u64 val)
+static int spufs_srr0_set(void *data, u64 val)
 {
         struct spu_context *ctx = data;
         struct spu_lscsa *lscsa = ctx->csa.lscsa;
         spu_acquire_saved(ctx);
         lscsa->srr0.slot[0] = (u32) val;
         spu_release_saved(ctx);
+
+        return 0;
 }
 
 static u64 spufs_srr0_get(struct spu_context *ctx)
@@ -1747,10 +1875,12 @@ static u64 spufs_object_id_get(struct spu_context *ctx)
         return ctx->object_id;
 }
 
-static void spufs_object_id_set(void *data, u64 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,