Hi David,
On Wed, 31 May 2017 16:58:48 +0200 David Sterba <dste...@suse.cz> wrote:
>
> On Wed, May 31, 2017 at 02:29:20AM -0700, Omar Sandoval wrote:
> > diff --git a/fs/btrfs/free-space-tree.c b/fs/btrfs/free-space-tree.c
> > index fc0bd8406758..5abd3cd71144 100644
> > --- a/fs/btrfs/free-space-tree.c
> > +++ b/fs/btrfs/free-space-tree.c
> > @@ -153,21 +153,18 @@ static inline u32 free_space_bitmap_size(u64 size,
> > u32 sectorsize)
> >
> > static u8 *alloc_bitmap(u32 bitmap_size)
> > {
> > - void *mem;
> > + u8 *ret;
> > + unsigned int nofs_flag;
> >
> > /*
> > - * The allocation size varies, observed numbers were < 4K up to 16K.
> > - * Using vmalloc unconditionally would be too heavy, we'll try
> > - * contiguous allocations first.
> > + * GFP_NOFS doesn't work with kvmalloc(), but we really can't recurse
> > + * into the filesystem as the free space bitmap can be modified in the
> > + * critical section of a transaction commit.
> > */
> > - if (bitmap_size <= PAGE_SIZE)
> > - return kzalloc(bitmap_size, GFP_NOFS);
> > -
> > - mem = kzalloc(bitmap_size, GFP_NOFS | __GFP_NOWARN);
> > - if (mem)
> > - return mem;
> > -
> > - return __vmalloc(bitmap_size, GFP_NOFS | __GFP_ZERO, PAGE_KERNEL);
> > + nofs_flag = memalloc_nofs_save();
> > + ret = kvmalloc(bitmap_size, GFP_KERNEL);
> > + memalloc_nofs_restore(nofs_flag);
> > + return ret;
> > }
> >
> > int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans,
> >
> > Dave, would you prefer to replace the patch we have now or do an
> > incremental patch on top of it?
>
> I'll drop the patch "btrfs: Use kvzalloc instead of kzalloc/vmalloc in
> alloc_bitmap", please send an updated version.
Ping?
--
Cheers,
Stephen Rothwell
