KVM: MMU: protect kvm_mmu_change_mmu_pages with mmu_lock

[karo-tx-linux.git] / fs / libfs.c

diff --git a/fs/libfs.c b/fs/libfs.c
index 892d41cb3382842a8c1a4b205f6a67fbd38c888b..8fc2407d2fe6ddc87441c4a55a59e9bb75264637 100644 (file)
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -216,8 +216,8 @@ int get_sb_pseudo(struct file_system_type *fs_type, char *name,
 
        s->s_flags = MS_NOUSER;
        s->s_maxbytes = ~0ULL;
-       s->s_blocksize = 1024;
-       s->s_blocksize_bits = 10;
+       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;
@@ -360,7 +360,7 @@ int simple_write_begin(struct file *file, struct address_space *mapping,
        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;
 
@@ -512,6 +512,20 @@ void simple_release_fs(struct vfsmount **mount, int *count)
        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)
 {
@@ -528,6 +542,20 @@ ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
        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)
 {