Message ID | 1274398462.2257.7.camel@localhost |
---|---|
State | Accepted, archived |
Headers | show |
On 2010-05-20, at 17:34, Ben Hutchings wrote: > struct ext4_new_group_input needs to be converted because u64 has > only 32-bit alignment on some 32-bit architectures, notably i386. Sigh, it would have been nice to catch this when ext4_new_group_input was first created. I don't mind fixing the kernel, since this is clearly broken. However, we may as well go ahead and declare a new struct ext4_new_group_input that has the right alignment, rename and deprecate the old one (have resize2fs prefer the new one if available) and take the old one out in a few years. I hate this business of keeping around old cruft like this forever. struct compat_ext4_new_group_input { u32 group; u64 block_bitmap; u64 inode_bitmap; u64 inode_table; u32 blocks_count; u16 reserved_blocks; u16 unused; }; struct ext4_new_group_input { u64 group; u64 block_bitmap; u64 inode_bitmap; u64 inode_table; u64 blocks_count; u32 reserved_blocks; u32 unused; }; #define EXT2_IOC_GROUP_ADD _IOW('f', 8,struct ext2_new_group_input) #define EXT4_IOC_GROUP_ADD_OLD _IOW('f', 8,struct compat_ext4_new_group_input) #define EXT4_IOC_GROUP_ADD _IOW('f', 8,struct ext4_new_group_input) The resize/online.c code already has compat support for both 32-bit and 64-bit IOC numbers, so it isn't much effort to have it try a third variant for a couple of years. > +#if defined(__KERNEL__) && defined(CONFIG_COMPAT) > +struct compat_ext4_new_group_input { > + u32 group; > + compat_u64 block_bitmap; > + compat_u64 inode_bitmap; > + compat_u64 inode_table; > + u32 blocks_count; > + u16 reserved_blocks; > + u16 unused; > +}; > +#endif > + > /* The struct ext4_new_group_input in kernel space, with free_blocks_count */ > struct ext4_new_group_data { > __u32 group; > @@ -409,6 +424,7 @@ struct ext4_new_group_data { > #define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int) > #define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int) > #define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int) > +#define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input) > #ifdef CONFIG_JBD2_DEBUG > #define EXT4_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int) > #endif > diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c > index 66fa0b0..6ddec84 100644 > --- a/fs/ext4/ioctl.c > +++ b/fs/ext4/ioctl.c > @@ -373,8 +373,29 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > case EXT4_IOC32_SETRSVSZ: > cmd = EXT4_IOC_SETRSVSZ; > break; > - case EXT4_IOC_GROUP_ADD: > - break; > + case EXT4_IOC32_GROUP_ADD: { > + struct compat_ext4_new_group_input __user *uinput; > + struct ext4_new_group_input input; > + mm_segment_t old_fs; > + int err; > + > + uinput = compat_ptr(arg); > + err = get_user(input.group, &uinput->group); > + err |= get_user(input.block_bitmap, &uinput->block_bitmap); > + err |= get_user(input.inode_bitmap, &uinput->inode_bitmap); > + err |= get_user(input.inode_table, &uinput->inode_table); > + err |= get_user(input.blocks_count, &uinput->blocks_count); > + err |= get_user(input.reserved_blocks, > + &uinput->reserved_blocks); > + if (err) > + return -EFAULT; > + old_fs = get_fs(); > + set_fs(KERNEL_DS); > + err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD, > + (unsigned long) &input); > + set_fs(old_fs); > + return err; > + } > case EXT4_IOC_MOVE_EXT: > break; > default: > -- > 1.7.1 > > Cheers, Andreas -- Andreas Dilger Lustre Technical Lead Oracle Corporation Canada Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 20, 2010 at 10:41:20PM -0600, Andreas Dilger wrote: > On 2010-05-20, at 17:34, Ben Hutchings wrote: > > struct ext4_new_group_input needs to be converted because u64 has > > only 32-bit alignment on some 32-bit architectures, notably i386. > > Sigh, it would have been nice to catch this when ext4_new_group_input was first created. > > I don't mind fixing the kernel, since this is clearly broken. > However, we may as well go ahead and declare a new struct > ext4_new_group_input that has the right alignment, rename and > deprecate the old one (have resize2fs prefer the new one if > available) and take the old one out in a few years. I hate this > business of keeping around old cruft like this forever. Well, in the long run we need a new ioctl which is compatible with flex_bg, which means doing multiple groups at once, and letting the kernel do much more of the work of selecting the block and inode numbers. And of course to support 2**64 blocks we need to support the meta_bg style of resizing. So we need to do some thinking about how to support resizing in the long-term anyway. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, May 21, 2010 at 12:34:22AM +0100, Ben Hutchings wrote: > struct ext4_new_group_input needs to be converted because u64 has > only 32-bit alignment on some 32-bit architectures, notably i386. > > Signed-off-by: Ben Hutchings <ben@decadent.org.uk> > --- Thanks for your patches. Both have been applied to the ext4 tree. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index f5c9941..ff540f7 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -29,6 +29,9 @@ #include <linux/wait.h> #include <linux/blockgroup_lock.h> #include <linux/percpu_counter.h> +#ifdef __KERNEL__ +#include <linux/compat.h> +#endif /* * The fourth extended filesystem constants/structures @@ -332,6 +335,18 @@ struct ext4_new_group_input { __u16 unused; }; +#if defined(__KERNEL__) && defined(CONFIG_COMPAT) +struct compat_ext4_new_group_input { + u32 group; + compat_u64 block_bitmap; + compat_u64 inode_bitmap; + compat_u64 inode_table; + u32 blocks_count; + u16 reserved_blocks; + u16 unused; +}; +#endif + /* The struct ext4_new_group_input in kernel space, with free_blocks_count */ struct ext4_new_group_data { __u32 group; @@ -409,6 +424,7 @@ struct ext4_new_group_data { #define EXT4_IOC32_GETRSVSZ _IOR('f', 5, int) #define EXT4_IOC32_SETRSVSZ _IOW('f', 6, int) #define EXT4_IOC32_GROUP_EXTEND _IOW('f', 7, unsigned int) +#define EXT4_IOC32_GROUP_ADD _IOW('f', 8, struct compat_ext4_new_group_input) #ifdef CONFIG_JBD2_DEBUG #define EXT4_IOC32_WAIT_FOR_READONLY _IOR('f', 99, int) #endif diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 66fa0b0..6ddec84 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -373,8 +373,29 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case EXT4_IOC32_SETRSVSZ: cmd = EXT4_IOC_SETRSVSZ; break; - case EXT4_IOC_GROUP_ADD: - break; + case EXT4_IOC32_GROUP_ADD: { + struct compat_ext4_new_group_input __user *uinput; + struct ext4_new_group_input input; + mm_segment_t old_fs; + int err; + + uinput = compat_ptr(arg); + err = get_user(input.group, &uinput->group); + err |= get_user(input.block_bitmap, &uinput->block_bitmap); + err |= get_user(input.inode_bitmap, &uinput->inode_bitmap); + err |= get_user(input.inode_table, &uinput->inode_table); + err |= get_user(input.blocks_count, &uinput->blocks_count); + err |= get_user(input.reserved_blocks, + &uinput->reserved_blocks); + if (err) + return -EFAULT; + old_fs = get_fs(); + set_fs(KERNEL_DS); + err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD, + (unsigned long) &input); + set_fs(old_fs); + return err; + } case EXT4_IOC_MOVE_EXT: break; default:
struct ext4_new_group_input needs to be converted because u64 has only 32-bit alignment on some 32-bit architectures, notably i386. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> --- Found and tested by myself on a Debian 2.6.32 kernel. This patch is based on linux-next. Ben. fs/ext4/ext4.h | 16 ++++++++++++++++ fs/ext4/ioctl.c | 25 +++++++++++++++++++++++-- 2 files changed, 39 insertions(+), 2 deletions(-)