#include <linux/vfs.h>
#include <linux/mutex.h>
#include <linux/exportfs.h>
+#include <linux/writeback.h>
+#include <linux/buffer_head.h>
#include <asm/uaccess.h>
*/
struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
- static struct dentry_operations simple_dentry_operations = {
+ static const struct dentry_operations simple_dentry_operations = {
.d_delete = simple_delete_dentry,
};
return PTR_ERR(s);
s->s_flags = MS_NOUSER;
- s->s_maxbytes = ~0ULL;
- s->s_blocksize = 1024;
- s->s_blocksize_bits = 10;
+ s->s_maxbytes = MAX_LFS_FILESIZE;
+ s->s_blocksize = PAGE_SIZE;
+ s->s_blocksize_bits = PAGE_SHIFT;
s->s_magic = magic;
s->s_op = ops ? ops : &simple_super_operations;
s->s_time_gran = 1;
*/
root->i_ino = 1;
root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
- root->i_uid = root->i_gid = 0;
root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
dentry = d_alloc(NULL, &d_name);
if (!dentry) {
d_instantiate(dentry, root);
s->s_root = dentry;
s->s_flags |= MS_ACTIVE;
- return simple_set_mnt(mnt, s);
+ simple_set_mnt(mnt, s);
+ return 0;
Enomem:
- up_write(&s->s_umount);
- deactivate_super(s);
+ deactivate_locked_super(s);
return -ENOMEM;
}
index = pos >> PAGE_CACHE_SHIFT;
from = pos & (PAGE_CACHE_SIZE - 1);
- page = __grab_cache_page(mapping, index);
+ page = grab_cache_page_write_begin(mapping, index, flags);
if (!page)
return -ENOMEM;
*/
inode->i_ino = 1;
inode->i_mode = S_IFDIR | 0755;
- inode->i_uid = inode->i_gid = 0;
- inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
if (!inode)
goto out;
inode->i_mode = S_IFREG | files->mode;
- inode->i_uid = inode->i_gid = 0;
- inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_fop = files->ops;
inode->i_ino = i;
mntput(mnt);
}
+/**
+ * simple_read_from_buffer - copy data from the buffer to user space
+ * @to: the user space buffer to read to
+ * @count: the maximum number of bytes to read
+ * @ppos: the current position in the buffer
+ * @from: the buffer to read from
+ * @available: the size of the buffer
+ *
+ * The simple_read_from_buffer() function reads up to @count bytes from the
+ * buffer @from at offset @ppos into the user space address starting at @to.
+ *
+ * On success, the number of bytes read is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
const void *from, size_t available)
{
loff_t pos = *ppos;
+ size_t ret;
+
if (pos < 0)
return -EINVAL;
- if (pos >= available)
+ if (pos >= available || !count)
return 0;
if (count > available - pos)
count = available - pos;
- if (copy_to_user(to, from + pos, count))
+ ret = copy_to_user(to, from + pos, count);
+ if (ret == count)
return -EFAULT;
+ count -= ret;
+ *ppos = pos + count;
+ return count;
+}
+
+/**
+ * memory_read_from_buffer - copy data from the buffer
+ * @to: the kernel space buffer to read to
+ * @count: the maximum number of bytes to read
+ * @ppos: the current position in the buffer
+ * @from: the buffer to read from
+ * @available: the size of the buffer
+ *
+ * The memory_read_from_buffer() function reads up to @count bytes from the
+ * buffer @from at offset @ppos into the kernel space address starting at @to.
+ *
+ * On success, the number of bytes read is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
+ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
+ const void *from, size_t available)
+{
+ loff_t pos = *ppos;
+
+ if (pos < 0)
+ return -EINVAL;
+ if (pos >= available)
+ return 0;
+ if (count > available - pos)
+ count = available - pos;
+ memcpy(to, from + pos, count);
*ppos = pos + count;
+
return count;
}
* possibly a read which collects the result - which is stored in a
* file-local buffer.
*/
+
+void simple_transaction_set(struct file *file, size_t n)
+{
+ struct simple_transaction_argresp *ar = file->private_data;
+
+ BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
+
+ /*
+ * The barrier ensures that ar->size will really remain zero until
+ * ar->data is ready for reading.
+ */
+ smp_mb();
+ ar->size = n;
+}
+
char *simple_transaction_get(struct file *file, const char __user *buf, size_t size)
{
struct simple_transaction_argresp *ar;
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);
+ ret = attr->set(attr->data, val);
+ if (ret == 0)
+ ret = len; /* on success, claim we got the whole input */
out:
mutex_unlock(&attr->mutex);
return ret;
}
-/*
- * This is what d_alloc_anon should have been. Once the exportfs
- * argument transition has been finished I will update d_alloc_anon
- * to this prototype and this wrapper will go away. --hch
- */
-static struct dentry *exportfs_d_alloc(struct inode *inode)
-{
- struct dentry *dentry;
-
- if (!inode)
- return NULL;
- if (IS_ERR(inode))
- return ERR_PTR(PTR_ERR(inode));
-
- dentry = d_alloc_anon(inode);
- if (!dentry) {
- iput(inode);
- dentry = ERR_PTR(-ENOMEM);
- }
- return dentry;
-}
-
/**
* generic_fh_to_dentry - generic helper for the fh_to_dentry export operation
* @sb: filesystem to do the file handle conversion on
break;
}
- return exportfs_d_alloc(inode);
+ return d_obtain_alias(inode);
}
EXPORT_SYMBOL_GPL(generic_fh_to_dentry);
break;
}
- return exportfs_d_alloc(inode);
+ return d_obtain_alias(inode);
}
EXPORT_SYMBOL_GPL(generic_fh_to_parent);
+int simple_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = 0, /* metadata-only; caller takes care of data */
+ };
+ struct inode *inode = dentry->d_inode;
+ int err;
+ int ret;
+
+ ret = sync_mapping_buffers(inode->i_mapping);
+ if (!(inode->i_state & I_DIRTY))
+ return ret;
+ if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
+ return ret;
+
+ err = sync_inode(inode, &wbc);
+ if (ret == 0)
+ ret = err;
+ return ret;
+}
+EXPORT_SYMBOL(simple_fsync);
+
EXPORT_SYMBOL(dcache_dir_close);
EXPORT_SYMBOL(dcache_dir_lseek);
EXPORT_SYMBOL(dcache_dir_open);
EXPORT_SYMBOL(simple_link);
EXPORT_SYMBOL(simple_lookup);
EXPORT_SYMBOL(simple_pin_fs);
-EXPORT_SYMBOL(simple_prepare_write);
+EXPORT_UNUSED_SYMBOL(simple_prepare_write);
EXPORT_SYMBOL(simple_readpage);
EXPORT_SYMBOL(simple_release_fs);
EXPORT_SYMBOL(simple_rename);
EXPORT_SYMBOL(simple_sync_file);
EXPORT_SYMBOL(simple_unlink);
EXPORT_SYMBOL(simple_read_from_buffer);
+EXPORT_SYMBOL(memory_read_from_buffer);
+EXPORT_SYMBOL(simple_transaction_set);
EXPORT_SYMBOL(simple_transaction_get);
EXPORT_SYMBOL(simple_transaction_read);
EXPORT_SYMBOL(simple_transaction_release);