From d78a3eda6985e74bc21a23362f27526f73e71649 Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Wed, 11 Aug 2010 14:17:27 -0700 Subject: [PATCH] kernel/kfifo.c: add handling of chained scatterlists The current kfifo scatterlist implementation will not work with chained scatterlists. It assumes that struct scatterlist arrays are allocated contiguously, which is not the case when chained scatterlists (struct sg_table) are in use. Signed-off-by: Stefani Seibold Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 02192dd905cc..4502604ecadf 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -10,7 +10,7 @@ * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License @@ -333,17 +333,16 @@ static int setup_sgl_buf(struct scatterlist *sgl, void *buf, buf += PAGE_SIZE; npage = virt_to_page(buf); if (page_to_phys(page) != page_to_phys(npage) - l) { - sgl->page_link = 0; - sg_set_page(sgl++, page, l - off, off); - if (++n == nents) + sg_set_page(sgl, page, l - off, off); + sgl = sg_next(sgl); + if (++n == nents || sgl == NULL) return n; page = npage; len -= l - off; l = off = 0; } } - sgl->page_link = 0; - sg_set_page(sgl++, page, len, off); + sg_set_page(sgl, page, len, off); return n + 1; } @@ -363,7 +362,7 @@ static unsigned int setup_sgl(struct __kfifo *fifo, struct scatterlist *sgl, } l = min(len, size - off); - n = setup_sgl_buf(sgl, fifo->data + off, nents, l); + n = setup_sgl_buf(sgl, fifo->data + off, nents, l); n += setup_sgl_buf(sgl + n, fifo->data, nents - n, len - l); if (n) -- 2.20.1