libata: fix ata_pio_sector for CONFIG_HIGHMEM

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>
This commit is contained in:
Christoph Hellwig 2021-07-09 15:02:37 +02:00 committed by Jens Axboe
parent f55966571d
commit ecef6a9eff
1 changed files with 27 additions and 8 deletions

View File

@ -637,6 +637,20 @@ unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf,
} }
EXPORT_SYMBOL_GPL(ata_sff_data_xfer32); 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. * ata_pio_sector - Transfer a sector of data.
* @qc: Command on going * @qc: Command on going
@ -648,11 +662,9 @@ EXPORT_SYMBOL_GPL(ata_sff_data_xfer32);
*/ */
static void ata_pio_sector(struct ata_queued_cmd *qc) 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 ata_port *ap = qc->ap;
struct page *page; struct page *page;
unsigned int offset; unsigned int offset;
unsigned char *buf;
if (!qc->cursg) { if (!qc->cursg) {
qc->curbytes = qc->nbytes; qc->curbytes = qc->nbytes;
@ -670,13 +682,20 @@ static void ata_pio_sector(struct ata_queued_cmd *qc)
DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read"); DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
/* do the actual data transfer */ /*
buf = kmap_atomic(page); * Split the transfer when it splits a page boundary. Note that the
ap->ops->sff_data_xfer(qc, buf + offset, qc->sect_size, do_write); * split still has to be dword aligned like all ATA data transfers.
kunmap_atomic(buf); */
WARN_ON_ONCE(offset % 4);
if (offset + qc->sect_size > PAGE_SIZE) {
unsigned int split_len = PAGE_SIZE - offset;
if (!do_write && !PageSlab(page)) ata_pio_xfer(qc, page, offset, split_len);
flush_dcache_page(page); 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->curbytes += qc->sect_size;
qc->cursg_ofs += qc->sect_size; qc->cursg_ofs += qc->sect_size;