| Message ID | d6f31db1d2542e1b4ba66d4cea80d3891678aa5a.1638476031.git.christophe.jaillet@wanadoo.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] xen-blkfront: Use the bitmap API when applicable | expand |
On Thu, Dec 02, 2021 at 09:16:04PM +0100, Christophe JAILLET wrote: > Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid some > open-coded arithmetic in allocator arguments. > > Also change the corresponding 'kfree()' into 'bitmap_free()' to keep > consistency. > > Use 'bitmap_copy()' to avoid an explicit 'memcpy()' > > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Thanks, Roger.
On Tue, Dec 14, 2021 at 11:59:39AM +0100, Roger Pau Monné wrote: > On Thu, Dec 02, 2021 at 09:16:04PM +0100, Christophe JAILLET wrote: > > Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid some > > open-coded arithmetic in allocator arguments. > > > > Also change the corresponding 'kfree()' into 'bitmap_free()' to keep > > consistency. > > > > Use 'bitmap_copy()' to avoid an explicit 'memcpy()' > > > > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > > Acked-by: Roger Pau Monné <roger.pau@citrix.com> Oh, I see there's been further discussion on this to avoid relying implicitly on the size of the bitmap being rounded to the size of an unsigned long. I think a new version is expected then? Thanks, Roger.
Le 14/12/2021 à 12:08, Roger Pau Monné a écrit : > On Tue, Dec 14, 2021 at 11:59:39AM +0100, Roger Pau Monné wrote: >> On Thu, Dec 02, 2021 at 09:16:04PM +0100, Christophe JAILLET wrote: >>> Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid some >>> open-coded arithmetic in allocator arguments. >>> >>> Also change the corresponding 'kfree()' into 'bitmap_free()' to keep >>> consistency. >>> >>> Use 'bitmap_copy()' to avoid an explicit 'memcpy()' >>> >>> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> >> >> Acked-by: Roger Pau Monné <roger.pau@citrix.com> > > Oh, I see there's been further discussion on this to avoid relying > implicitly on the size of the bitmap being rounded to the size of an > unsigned long. I think a new version is expected then? > > Thanks, Roger. > Yes, I'll send a patch in order to add a 'bitmap_size()' I'll update this patch when/if it is merged. You can drop it for now. CJ
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 700c765a759a..69cf13608ce0 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -442,22 +442,20 @@ static int xlbd_reserve_minors(unsigned int minor, unsigned int nr) if (end > nr_minors) { unsigned long *bitmap, *old; - bitmap = kcalloc(BITS_TO_LONGS(end), sizeof(*bitmap), - GFP_KERNEL); + bitmap = bitmap_zalloc(end, GFP_KERNEL); if (bitmap == NULL) return -ENOMEM; spin_lock(&minor_lock); if (end > nr_minors) { old = minors; - memcpy(bitmap, minors, - BITS_TO_LONGS(nr_minors) * sizeof(*bitmap)); + bitmap_copy(bitmap, minors, nr_minors); minors = bitmap; nr_minors = BITS_TO_LONGS(end) * BITS_PER_LONG; } else old = bitmap; spin_unlock(&minor_lock); - kfree(old); + bitmap_free(old); } spin_lock(&minor_lock); @@ -2610,7 +2608,7 @@ static void __exit xlblk_exit(void) xenbus_unregister_driver(&blkfront_driver); unregister_blkdev(XENVBD_MAJOR, DEV_NAME); - kfree(minors); + bitmap_free(minors); } module_exit(xlblk_exit);
Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid some open-coded arithmetic in allocator arguments. Also change the corresponding 'kfree()' into 'bitmap_free()' to keep consistency. Use 'bitmap_copy()' to avoid an explicit 'memcpy()' Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> --- v1 --> v2: change another kfree into bitmap_free --- drivers/block/xen-blkfront.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)