Messages in this thread Patch in this message | | | From | Sasha Levin <> | Subject | [PATCH AUTOSEL 4.19 1/5] libata: fix ata_pio_sector for CONFIG_HIGHMEM | Date | Tue, 3 Aug 2021 07:44:25 -0400 |
| |
From: Christoph Hellwig <hch@lst.de>
[ Upstream commit ecef6a9effe49e8e2635c839020b9833b71e934c ]
Data transfers are not required to be block aligned in memory, so they span two pages. Fix this by splitting the call to >sff_data_xfer into two for that case.
This has been broken since the initial libata import before the damn of git, but was uncovered by the legacy ide driver removal.
Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210709130237.3730959-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/ata/libata-sff.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-)
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 7484ffdabd54..ec62d26c32a9 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -657,6 +657,20 @@ unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf, } EXPORT_SYMBOL_GPL(ata_sff_data_xfer32); +static void ata_pio_xfer(struct ata_queued_cmd *qc, struct page *page, + unsigned int offset, size_t xfer_size) +{ + bool do_write = (qc->tf.flags & ATA_TFLAG_WRITE); + unsigned char *buf; + + buf = kmap_atomic(page); + qc->ap->ops->sff_data_xfer(qc, buf + offset, xfer_size, do_write); + kunmap_atomic(buf); + + if (!do_write && !PageSlab(page)) + flush_dcache_page(page); +} + /** * ata_pio_sector - Transfer a sector of data. * @qc: Command on going @@ -668,11 +682,9 @@ EXPORT_SYMBOL_GPL(ata_sff_data_xfer32); */ static void ata_pio_sector(struct ata_queued_cmd *qc) { - int do_write = (qc->tf.flags & ATA_TFLAG_WRITE); struct ata_port *ap = qc->ap; struct page *page; unsigned int offset; - unsigned char *buf; if (!qc->cursg) { qc->curbytes = qc->nbytes; @@ -690,13 +702,20 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read"); - /* do the actual data transfer */ - buf = kmap_atomic(page); - ap->ops->sff_data_xfer(qc, buf + offset, qc->sect_size, do_write); - kunmap_atomic(buf); + /* + * Split the transfer when it splits a page boundary. Note that the + * split still has to be dword aligned like all ATA data transfers. + */ + WARN_ON_ONCE(offset % 4); + if (offset + qc->sect_size > PAGE_SIZE) { + unsigned int split_len = PAGE_SIZE - offset; - if (!do_write && !PageSlab(page)) - flush_dcache_page(page); + ata_pio_xfer(qc, page, offset, split_len); + ata_pio_xfer(qc, nth_page(page, 1), 0, + qc->sect_size - split_len); + } else { + ata_pio_xfer(qc, page, offset, qc->sect_size); + } qc->curbytes += qc->sect_size; qc->cursg_ofs += qc->sect_size; -- 2.30.2
| |