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authorLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 02:51:46 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 02:51:46 +0400
commitb9394d8a657cd3c064fa432aa0905c1b58b38fe9 (patch)
tree5a0c98370f313fa11693ab72eea0dc809fd6567d /fs/efivarfs/file.c
parent126de6b20bfb82cc19012d5048f11f339ae5a021 (diff)
parent7b2dd6d2c4db3912771bfcfd7ac7264011a3c831 (diff)
downloadlinux-b9394d8a657cd3c064fa432aa0905c1b58b38fe9.tar.xz
Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/efi changes from Peter Anvin: "The bulk of these changes are cleaning up the efivars handling and breaking it up into a tree of files. There are a number of fixes as well. The entire changeset is pretty big, but most of it is code movement. Several of these commits are quite new; the history got very messed up due to a mismerge with the urgent changes for rc8 which completely broke IA64, and so Ingo requested that we rebase it to straighten it out." * 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi: remove "kfree(NULL)" efi: locking fix in efivar_entry_set_safe() efi, pstore: Read data from variable store before memcpy() efi, pstore: Remove entry from list when erasing efi, pstore: Initialise 'entry' before iterating efi: split efisubsystem from efivars efivarfs: Move to fs/efivarfs efivars: Move pstore code into the new EFI directory efivars: efivar_entry API efivars: Keep a private global pointer to efivars efi: move utf16 string functions to efi.h x86, efi: Make efi_memblock_x86_reserve_range more readable efivarfs: convert to use simple_open()
Diffstat (limited to 'fs/efivarfs/file.c')
-rw-r--r--fs/efivarfs/file.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c
new file mode 100644
index 000000000000..ede07fc7309f
--- /dev/null
+++ b/fs/efivarfs/file.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2012 Red Hat, Inc.
+ * Copyright (C) 2012 Jeremy Kerr <jeremy.kerr@canonical.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/efi.h>
+#include <linux/fs.h>
+
+#include "internal.h"
+
+static ssize_t efivarfs_file_write(struct file *file,
+ const char __user *userbuf, size_t count, loff_t *ppos)
+{
+ struct efivar_entry *var = file->private_data;
+ void *data;
+ u32 attributes;
+ struct inode *inode = file->f_mapping->host;
+ unsigned long datasize = count - sizeof(attributes);
+ ssize_t bytes = 0;
+ bool set = false;
+
+ if (count < sizeof(attributes))
+ return -EINVAL;
+
+ if (copy_from_user(&attributes, userbuf, sizeof(attributes)))
+ return -EFAULT;
+
+ if (attributes & ~(EFI_VARIABLE_MASK))
+ return -EINVAL;
+
+ data = kmalloc(datasize, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ if (copy_from_user(data, userbuf + sizeof(attributes), datasize)) {
+ bytes = -EFAULT;
+ goto out;
+ }
+
+ bytes = efivar_entry_set_get_size(var, attributes, &datasize,
+ data, &set);
+ if (!set && bytes)
+ goto out;
+
+ if (bytes == -ENOENT) {
+ drop_nlink(inode);
+ d_delete(file->f_dentry);
+ dput(file->f_dentry);
+ } else {
+ mutex_lock(&inode->i_mutex);
+ i_size_write(inode, datasize + sizeof(attributes));
+ mutex_unlock(&inode->i_mutex);
+ }
+
+ bytes = count;
+
+out:
+ kfree(data);
+
+ return bytes;
+}
+
+static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct efivar_entry *var = file->private_data;
+ unsigned long datasize = 0;
+ u32 attributes;
+ void *data;
+ ssize_t size = 0;
+ int err;
+
+ err = efivar_entry_size(var, &datasize);
+ if (err)
+ return err;
+
+ data = kmalloc(datasize + sizeof(attributes), GFP_KERNEL);
+
+ if (!data)
+ return -ENOMEM;
+
+ size = efivar_entry_get(var, &attributes, &datasize,
+ data + sizeof(attributes));
+ if (size)
+ goto out_free;
+
+ memcpy(data, &attributes, sizeof(attributes));
+ size = simple_read_from_buffer(userbuf, count, ppos,
+ data, datasize + sizeof(attributes));
+out_free:
+ kfree(data);
+
+ return size;
+}
+
+const struct file_operations efivarfs_file_operations = {
+ .open = simple_open,
+ .read = efivarfs_file_read,
+ .write = efivarfs_file_write,
+ .llseek = no_llseek,
+};