From: Christoph Hellwig hch@lst.de
stable inclusion from linux-4.19.203 commit 5d4f303010b717a05ec560dc1228918116f58637
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[ 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 Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- 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 7484ffdabd543..ec62d26c32a9d 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;