[PATCH] BLOCK: Move the loop device ioctl compat stuff to the loop driver [try #6]
authorDavid Howells <dhowells@redhat.com>
Tue, 29 Aug 2006 18:06:14 +0000 (19:06 +0100)
committerJens Axboe <axboe@nelson.home.kernel.dk>
Sat, 30 Sep 2006 18:52:27 +0000 (20:52 +0200)
Move the loop device ioctl compat stuff from fs/compat_ioctl.c to the loop
driver so that the loop header file doesn't need to be included.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
drivers/block/loop.c
fs/compat_ioctl.c
include/linux/compat_ioctl.h

index 68b0471..d6bb8da 100644 (file)
@@ -66,6 +66,7 @@
 #include <linux/swap.h>
 #include <linux/slab.h>
 #include <linux/loop.h>
+#include <linux/compat.h>
 #include <linux/suspend.h>
 #include <linux/writeback.h>
 #include <linux/buffer_head.h>         /* for invalidate_bdev() */
@@ -1165,6 +1166,162 @@ static int lo_ioctl(struct inode * inode, struct file * file,
        return err;
 }
 
+#ifdef CONFIG_COMPAT
+struct compat_loop_info {
+       compat_int_t    lo_number;      /* ioctl r/o */
+       compat_dev_t    lo_device;      /* ioctl r/o */
+       compat_ulong_t  lo_inode;       /* ioctl r/o */
+       compat_dev_t    lo_rdevice;     /* ioctl r/o */
+       compat_int_t    lo_offset;
+       compat_int_t    lo_encrypt_type;
+       compat_int_t    lo_encrypt_key_size;    /* ioctl w/o */
+       compat_int_t    lo_flags;       /* ioctl r/o */
+       char            lo_name[LO_NAME_SIZE];
+       unsigned char   lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
+       compat_ulong_t  lo_init[2];
+       char            reserved[4];
+};
+
+/*
+ * Transfer 32-bit compatibility structure in userspace to 64-bit loop info
+ * - noinlined to reduce stack space usage in main part of driver
+ */
+static noinline int
+loop_info64_from_compat(const struct compat_loop_info *arg,
+                       struct loop_info64 *info64)
+{
+       struct compat_loop_info info;
+
+       if (copy_from_user(&info, arg, sizeof(info)))
+               return -EFAULT;
+
+       memset(info64, 0, sizeof(*info64));
+       info64->lo_number = info.lo_number;
+       info64->lo_device = info.lo_device;
+       info64->lo_inode = info.lo_inode;
+       info64->lo_rdevice = info.lo_rdevice;
+       info64->lo_offset = info.lo_offset;
+       info64->lo_sizelimit = 0;
+       info64->lo_encrypt_type = info.lo_encrypt_type;
+       info64->lo_encrypt_key_size = info.lo_encrypt_key_size;
+       info64->lo_flags = info.lo_flags;
+       info64->lo_init[0] = info.lo_init[0];
+       info64->lo_init[1] = info.lo_init[1];
+       if (info.lo_encrypt_type == LO_CRYPT_CRYPTOAPI)
+               memcpy(info64->lo_crypt_name, info.lo_name, LO_NAME_SIZE);
+       else
+               memcpy(info64->lo_file_name, info.lo_name, LO_NAME_SIZE);
+       memcpy(info64->lo_encrypt_key, info.lo_encrypt_key, LO_KEY_SIZE);
+       return 0;
+}
+
+/*
+ * Transfer 64-bit loop info to 32-bit compatibility structure in userspace
+ * - noinlined to reduce stack space usage in main part of driver
+ */
+static noinline int
+loop_info64_to_compat(const struct loop_info64 *info64,
+                     struct compat_loop_info __user *arg)
+{
+       struct compat_loop_info info;
+
+       memset(&info, 0, sizeof(info));
+       info.lo_number = info64->lo_number;
+       info.lo_device = info64->lo_device;
+       info.lo_inode = info64->lo_inode;
+       info.lo_rdevice = info64->lo_rdevice;
+       info.lo_offset = info64->lo_offset;
+       info.lo_encrypt_type = info64->lo_encrypt_type;
+       info.lo_encrypt_key_size = info64->lo_encrypt_key_size;
+       info.lo_flags = info64->lo_flags;
+       info.lo_init[0] = info64->lo_init[0];
+       info.lo_init[1] = info64->lo_init[1];
+       if (info.lo_encrypt_type == LO_CRYPT_CRYPTOAPI)
+               memcpy(info.lo_name, info64->lo_crypt_name, LO_NAME_SIZE);
+       else
+               memcpy(info.lo_name, info64->lo_file_name, LO_NAME_SIZE);
+       memcpy(info.lo_encrypt_key, info64->lo_encrypt_key, LO_KEY_SIZE);
+
+       /* error in case values were truncated */
+       if (info.lo_device != info64->lo_device ||
+           info.lo_rdevice != info64->lo_rdevice ||
+           info.lo_inode != info64->lo_inode ||
+           info.lo_offset != info64->lo_offset ||
+           info.lo_init[0] != info64->lo_init[0] ||
+           info.lo_init[1] != info64->lo_init[1])
+               return -EOVERFLOW;
+
+       if (copy_to_user(arg, &info, sizeof(info)))
+               return -EFAULT;
+       return 0;
+}
+
+static int
+loop_set_status_compat(struct loop_device *lo,
+                      const struct compat_loop_info __user *arg)
+{
+       struct loop_info64 info64;
+       int ret;
+
+       ret = loop_info64_from_compat(arg, &info64);
+       if (ret < 0)
+               return ret;
+       return loop_set_status(lo, &info64);
+}
+
+static int
+loop_get_status_compat(struct loop_device *lo,
+                      struct compat_loop_info __user *arg)
+{
+       struct loop_info64 info64;
+       int err = 0;
+
+       if (!arg)
+               err = -EINVAL;
+       if (!err)
+               err = loop_get_status(lo, &info64);
+       if (!err)
+               err = loop_info64_to_compat(&info64, arg);
+       return err;
+}
+
+static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+       struct inode *inode = file->f_dentry->d_inode;
+       struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
+       int err;
+
+       lock_kernel();
+       switch(cmd) {
+       case LOOP_SET_STATUS:
+               mutex_lock(&lo->lo_ctl_mutex);
+               err = loop_set_status_compat(
+                       lo, (const struct compat_loop_info __user *) arg);
+               mutex_unlock(&lo->lo_ctl_mutex);
+               break;
+       case LOOP_GET_STATUS:
+               mutex_lock(&lo->lo_ctl_mutex);
+               err = loop_get_status_compat(
+                       lo, (struct compat_loop_info __user *) arg);
+               mutex_unlock(&lo->lo_ctl_mutex);
+               break;
+       case LOOP_CLR_FD:
+       case LOOP_GET_STATUS64:
+       case LOOP_SET_STATUS64:
+               arg = (unsigned long) compat_ptr(arg);
+       case LOOP_SET_FD:
+       case LOOP_CHANGE_FD:
+               err = lo_ioctl(inode, file, cmd, arg);
+               break;
+       default:
+               err = -ENOIOCTLCMD;
+               break;
+       }
+       unlock_kernel();
+       return err;
+}
+#endif
+
 static int lo_open(struct inode *inode, struct file *file)
 {
        struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
@@ -1192,6 +1349,9 @@ static struct block_device_operations lo_fops = {
        .open =         lo_open,
        .release =      lo_release,
        .ioctl =        lo_ioctl,
+#ifdef CONFIG_COMPAT
+       .compat_ioctl = lo_compat_ioctl,
+#endif
 };
 
 /*
index ab74c9b..3b0cf7f 100644 (file)
@@ -40,7 +40,6 @@
 #include <linux/if_pppox.h>
 #include <linux/mtio.h>
 #include <linux/cdrom.h>
-#include <linux/loop.h>
 #include <linux/auto_fs.h>
 #include <linux/auto_fs4.h>
 #include <linux/tty.h>
@@ -1214,71 +1213,6 @@ static int cdrom_ioctl_trans(unsigned int fd, unsigned int cmd, unsigned long ar
        return err;
 }
 
-struct loop_info32 {
-       compat_int_t    lo_number;      /* ioctl r/o */
-       compat_dev_t    lo_device;      /* ioctl r/o */
-       compat_ulong_t  lo_inode;       /* ioctl r/o */
-       compat_dev_t    lo_rdevice;     /* ioctl r/o */
-       compat_int_t    lo_offset;
-       compat_int_t    lo_encrypt_type;
-       compat_int_t    lo_encrypt_key_size;    /* ioctl w/o */
-       compat_int_t    lo_flags;       /* ioctl r/o */
-       char            lo_name[LO_NAME_SIZE];
-       unsigned char   lo_encrypt_key[LO_KEY_SIZE]; /* ioctl w/o */
-       compat_ulong_t  lo_init[2];
-       char            reserved[4];
-};
-
-static int loop_status(unsigned int fd, unsigned int cmd, unsigned long arg)
-{
-       mm_segment_t old_fs = get_fs();
-       struct loop_info l;
-       struct loop_info32 __user *ul;
-       int err = -EINVAL;
-
-       ul = compat_ptr(arg);
-       switch(cmd) {
-       case LOOP_SET_STATUS:
-               err = get_user(l.lo_number, &ul->lo_number);
-               err |= __get_user(l.lo_device, &ul->lo_device);
-               err |= __get_user(l.lo_inode, &ul->lo_inode);
-               err |= __get_user(l.lo_rdevice, &ul->lo_rdevice);
-               err |= __copy_from_user(&l.lo_offset, &ul->lo_offset,
-                       8 + (unsigned long)l.lo_init - (unsigned long)&l.lo_offset);
-               if (err) {
-                       err = -EFAULT;
-               } else {
-                       set_fs (KERNEL_DS);
-                       err = sys_ioctl (fd, cmd, (unsigned long)&l);
-                       set_fs (old_fs);
-               }
-               break;
-       case LOOP_GET_STATUS:
-               set_fs (KERNEL_DS);
-               err = sys_ioctl (fd, cmd, (unsigned long)&l);
-               set_fs (old_fs);
-               if (!err) {
-                       err = put_user(l.lo_number, &ul->lo_number);
-                       err |= __put_user(l.lo_device, &ul->lo_device);
-                       err |= __put_user(l.lo_inode, &ul->lo_inode);
-                       err |= __put_user(l.lo_rdevice, &ul->lo_rdevice);
-                       err |= __copy_to_user(&ul->lo_offset, &l.lo_offset,
-                               (unsigned long)l.lo_init - (unsigned long)&l.lo_offset);
-                       if (err)
-                               err = -EFAULT;
-               }
-               break;
-       default: {
-               static int count;
-               if (++count <= 20)
-                       printk("%s: Unknown loop ioctl cmd, fd(%d) "
-                              "cmd(%08x) arg(%08lx)\n",
-                              __FUNCTION__, fd, cmd, arg);
-       }
-       }
-       return err;
-}
-
 #ifdef CONFIG_VT
 
 static int vt_check(struct file *file)
@@ -2808,8 +2742,6 @@ HANDLE_IOCTL(MTIOCGET32, mt_ioctl_trans)
 HANDLE_IOCTL(MTIOCPOS32, mt_ioctl_trans)
 HANDLE_IOCTL(CDROMREADAUDIO, cdrom_ioctl_trans)
 HANDLE_IOCTL(CDROM_SEND_PACKET, cdrom_ioctl_trans)
-HANDLE_IOCTL(LOOP_SET_STATUS, loop_status)
-HANDLE_IOCTL(LOOP_GET_STATUS, loop_status)
 #define AUTOFS_IOC_SETTIMEOUT32 _IOWR(0x93,0x64,unsigned int)
 HANDLE_IOCTL(AUTOFS_IOC_SETTIMEOUT32, ioc_settimeout)
 #ifdef CONFIG_VT
index bea0255..98d40e0 100644 (file)
@@ -395,12 +395,6 @@ COMPATIBLE_IOCTL(DVD_WRITE_STRUCT)
 COMPATIBLE_IOCTL(DVD_AUTH)
 /* pktcdvd */
 COMPATIBLE_IOCTL(PACKET_CTRL_CMD)
-/* Big L */
-ULONG_IOCTL(LOOP_SET_FD)
-ULONG_IOCTL(LOOP_CHANGE_FD)
-COMPATIBLE_IOCTL(LOOP_CLR_FD)
-COMPATIBLE_IOCTL(LOOP_GET_STATUS64)
-COMPATIBLE_IOCTL(LOOP_SET_STATUS64)
 /* Big A */
 /* sparc only */
 /* Big Q for sound/OSS */