> > -#define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC|FIEMAP_FLAG_XATTR)
> > +#define EXT4_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC | \
> > + FIEMAP_FLAG_XATTR| \
> > + FIEMAP_KERNEL_FIBMAP)
> >
> > static int ext4_xattr_fiemap(struct inode *inode,
> > struct fiemap_extent_info *fieinfo)
> > @@ -5048,6 +5050,9 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo)
> > if (ext4_has_inline_data(inode)) {
> > int has_inline = 1;
> >
> > + if (fieinfo->fi_flags & FIEMAP_KERNEL_FIBMAP)
> > + return -EINVAL;
>
> Wouldn't the inline data case be caught by fiemap_bmap and turned into
> -EINVAL?
Yes, it does, but until ext4_fiemap() returns the extent with the INLINE flag,
it does need to go through the whole fiemap mapping mechanism when we already
know the result... So, instead of letting the ext4_fiemap() map the extent, just
take the shortcut and return -EINVAL directly.
The check in fiemap_bmap() is a 'safe measure' (if it does have other name I
don't know :), but if the filesystem already knows it's gonna fall into an
inline inode, taking the shortcut is better, isn't it?
> > + return 1;
> > + return 0;
> > +}
> > +
> > +static int bmap_fiemap(struct inode *inode, sector_t *block)
> > +{
> > + struct fiemap_extent_info fieinfo = { 0, };
> > + struct fiemap_extent fextent;
> > + u64 start = *block << inode->i_blkbits;
> > + int error = -EINVAL;
> > +
> > + fextent.fe_logical = 0;
> > + fextent.fe_physical = 0;
> > + fieinfo.fi_extents_max = 1;
> > + fieinfo.fi_extents_mapped = 0;
> > + fieinfo.fi_cb_data = &fextent;
> > + fieinfo.fi_start = start;
> > + fieinfo.fi_len = 1 << inode->i_blkbits;
> > + fieinfo.fi_cb = fiemap_fill_kernel_extent;
> > + fieinfo.fi_flags = (FIEMAP_KERNEL_FIBMAP | FIEMAP_FLAG_SYNC);
> > +
> > + error = inode->i_op->fiemap(inode, &fieinfo);
> > +
> > + if (error)
> > + return error;
> > +
> > + if (fieinfo.fi_flags & (FIEMAP_EXTENT_UNKNOWN |
> > + FIEMAP_EXTENT_ENCODED |
> > + FIEMAP_EXTENT_DATA_INLINE |
> > + FIEMAP_EXTENT_UNWRITTEN |
> > + FIEMAP_EXTENT_SHARED))
> > + return -EINVAL;
> > +
> > + *block = (fextent.fe_physical +
> > + (start - fextent.fe_logical)) >> inode->i_blkbits;
> > +
> > + return error;
> > +}
> > +
> > /**
> > * bmap - find a block number in a file
> > * @inode: inode owning the block number being requested
> > @@ -1591,10 +1663,15 @@ EXPORT_SYMBOL(iput);
> > */
> > int bmap(struct inode *inode, sector_t *block)
> > {
> > - if (!inode->i_mapping->a_ops->bmap)
> > + if (inode->i_op->fiemap)
> > + return bmap_fiemap(inode, block);
> > +
> > + if (inode->i_mapping->a_ops->bmap)
> > + *block = inode->i_mapping->a_ops->bmap(inode->i_mapping,
> > + *block);
> > + else
> > return -EINVAL;
> >
> > - *block = inode->i_mapping->a_ops->bmap(inode->i_mapping, *block);
> > return 0;
> > }
> > EXPORT_SYMBOL(bmap);
> > diff --git a/fs/ioctl.c b/fs/ioctl.c
> > index d72696c222de..0759ac6e4c7e 100644
> > --- a/fs/ioctl.c
> > +++ b/fs/ioctl.c
> > @@ -77,11 +77,8 @@ static int ioctl_fibmap(struct file *filp, int __user *p)
> > return error;
> > }
> >
> > -#define SET_UNKNOWN_FLAGS (FIEMAP_EXTENT_DELALLOC)
> > -#define SET_NO_UNMOUNTED_IO_FLAGS (FIEMAP_EXTENT_DATA_ENCRYPTED)
> > -#define SET_NOT_ALIGNED_FLAGS (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
> > -int fiemap_fill_user_extent(struct fiemap_extent_info *fieinfo, u64 logical,
> > - u64 phys, u64 len, u32 flags)
> > +static int fiemap_fill_user_extent(struct fiemap_extent_info *fieinfo,
> > + u64 logical, u64 phys, u64 len, u32 flags)
> > {
> > struct fiemap_extent extent;
> > struct fiemap_extent __user *dest = fieinfo->fi_cb_data;
> > @@ -89,17 +86,17 @@ int fiemap_fill_user_extent(struct fiemap_extent_info *fieinfo, u64 logical,
> > /* only count the extents */
> > if (fieinfo->fi_extents_max == 0) {
> > fieinfo->fi_extents_mapped++;
> > - return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
> > + goto out;
> > }
> >
> > if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
> > return 1;
> >
> > - if (flags & SET_UNKNOWN_FLAGS)
> > + if (flags & FIEMAP_EXTENT_DELALLOC)
> > flags |= FIEMAP_EXTENT_UNKNOWN;
> > - if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
> > + if (flags & FIEMAP_EXTENT_DATA_ENCRYPTED)
> > flags |= FIEMAP_EXTENT_ENCODED;
> > - if (flags & SET_NOT_ALIGNED_FLAGS)
>
> It's too bad that we lose the "not aligned" semantic meaning here.
May you explain a bit better what you mean? We don't lose it, just the define
goes away, the reason I dropped these defines is because the same flags are used
in both functions, fiemap_fill_{user,kernel}_extent(), and I didn't think
defining them on both places (or in fs.h) has any benefit here, so I opted to
remove them.
>
> > + if (flags & (FIEMAP_EXTENT_DATA_TAIL | FIEMAP_EXTENT_DATA_INLINE))
> > flags |= FIEMAP_EXTENT_NOT_ALIGNED;
>
> Why doesn't this function just call fiemap_fill_kernel_extent to fill
> out the onstack @extent structure? We've now implemented "fill out out
> a struct fiemap_extent" twice.
fiemap_fill_{user, kernel}_extent() have different purposes, and the big
difference is one handles a userspace pointer memory and the other don't. IIRC
the original proposal was some sort of sharing a single function, but then
Christoph suggested a new design, using different functions as callbacks.
> > diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> > index b485190b7ecd..18a798e9076b 100644
> > --- a/fs/xfs/xfs_iops.c
> > +++ b/fs/xfs/xfs_iops.c
> > @@ -1113,6 +1113,11 @@ xfs_vn_fiemap(
> > struct fiemap_extent_info *fieinfo)
> > {
> > int error;
> > + struct xfs_inode *ip = XFS_I(inode);
>
> Would you mind fixing the indentation to match usual xfs style?
Sure, will fix it
>
> > +
> > + if (fieinfo->fi_flags & FIEMAP_KERNEL_FIBMAP)
> > + if (xfs_is_reflink_inode(ip) || XFS_IS_REALTIME_INODE(ip))
> > + return -EINVAL;
>
> The xfs part looks ok to me.
>
> --D
>
--
Carlos
