On Mon, Dec 17, 2012 at 12:13:36AM +0800, Zheng Liu wrote: > On Thu, Dec 13, 2012 at 12:08:11AM -0800, Darrick J. Wong wrote: > > diff --git a/mm/bounce.c b/mm/bounce.c > > index 0420867..fa11935 100644 > > --- a/mm/bounce.c > > +++ b/mm/bounce.c > > @@ -178,6 +178,38 @@ static void bounce_end_io_read_isa(struct bio *bio, > > int err) > > __bounce_end_io_read(bio, isa_page_pool, err); > > } > > > > +#ifdef CONFIG_NEED_BOUNCE_POOL > > +static int might_snapshot_stable_page_write(struct bio **bio_orig) > > +{ > > + return bio_data_dir(*bio_orig) == WRITE; > > +} > > + > > +static int should_snapshot_stable_pages(struct page *page, int rw) > > +{ > > + struct backing_dev_info *bdi; > > + struct address_space *mapping = page_mapping(page); > > + > > + if (!mapping) > > + return 0; > > + bdi = mapping->backing_dev_info; > > + if (!bdi_cap_stable_pages_required(bdi)) > > + return 0; > > + > > + return mapping->host->i_sb->s_flags & MS_SNAP_STABLE && > > + rw == WRITE; > > +} > > +#else > > +static int might_snapshot_stable_page_write(struct bio **bio_orig) > > +{ > > + return 0; > > +} > > + > > +static int should_snapshot_static_pages(struct page *page, int rw) > ^^^^^^ > It should be _stable_.
Good catch! Thank you! --D > > Regards, > - Zheng > > +{ > > + return 0; > > +} > > +#endif /* CONFIG_NEED_BOUNCE_POOL */ > > + > > static void __blk_queue_bounce(struct request_queue *q, struct bio > > **bio_orig, > > mempool_t *pool) > > { > > @@ -192,7 +224,8 @@ static void __blk_queue_bounce(struct request_queue *q, > > struct bio **bio_orig, > > /* > > * is destination page below bounce pfn? > > */ > > - if (page_to_pfn(page) <= queue_bounce_pfn(q)) > > + if (page_to_pfn(page) <= queue_bounce_pfn(q) && > > + !should_snapshot_stable_pages(page, rw)) > > continue; > > > > /* > > @@ -284,7 +317,8 @@ void blk_queue_bounce(struct request_queue *q, struct > > bio **bio_orig) > > * don't waste time iterating over bio segments > > */ > > if (!(q->bounce_gfp & GFP_DMA)) { > > - if (queue_bounce_pfn(q) >= blk_max_pfn) > > + if (queue_bounce_pfn(q) >= blk_max_pfn && > > + !might_snapshot_stable_page_write(bio_orig)) > > return; > > pool = page_pool; > > } else { > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/