6.15-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Fourier fourier.thomas@gmail.com
[ Upstream commit 8e1fab9cccc7b806b0cffdceabb09b310b83b553 ]
The dma_map_sg() can fail and, in case of failure, returns 0. If it fails, mtip_hw_submit_io() returns an error.
The dma_unmap_sg() requires the nents parameter to be the same as the one passed to dma_map_sg(). This patch saves the nents in command->scatter_ents.
Fixes: 88523a61558a ("block: Add driver for Micron RealSSD pcie flash cards") Signed-off-by: Thomas Fourier fourier.thomas@gmail.com Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Link: https://lore.kernel.org/r/20250627121123.203731-2-fourier.thomas@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/mtip32xx/mtip32xx.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-)
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c index 0d619df03fa9..fe3a0b8377db 100644 --- a/drivers/block/mtip32xx/mtip32xx.c +++ b/drivers/block/mtip32xx/mtip32xx.c @@ -2040,11 +2040,12 @@ static int mtip_hw_ioctl(struct driver_data *dd, unsigned int cmd, * @dir Direction (read or write) * * return value - * None + * 0 The IO completed successfully. + * -ENOMEM The DMA mapping failed. */ -static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq, - struct mtip_cmd *command, - struct blk_mq_hw_ctx *hctx) +static int mtip_hw_submit_io(struct driver_data *dd, struct request *rq, + struct mtip_cmd *command, + struct blk_mq_hw_ctx *hctx) { struct mtip_cmd_hdr *hdr = dd->port->command_list + sizeof(struct mtip_cmd_hdr) * rq->tag; @@ -2056,12 +2057,14 @@ static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq, unsigned int nents;
/* Map the scatter list for DMA access */ - nents = blk_rq_map_sg(rq, command->sg); - nents = dma_map_sg(&dd->pdev->dev, command->sg, nents, dma_dir); + command->scatter_ents = blk_rq_map_sg(rq, command->sg); + nents = dma_map_sg(&dd->pdev->dev, command->sg, + command->scatter_ents, dma_dir); + if (!nents) + return -ENOMEM;
- prefetch(&port->flags);
- command->scatter_ents = nents; + prefetch(&port->flags);
/* * The number of retries for this command before it is @@ -2112,11 +2115,13 @@ static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq, if (unlikely(port->flags & MTIP_PF_PAUSE_IO)) { set_bit(rq->tag, port->cmds_to_issue); set_bit(MTIP_PF_ISSUE_CMDS_BIT, &port->flags); - return; + return 0; }
/* Issue the command to the hardware */ mtip_issue_ncq_command(port, rq->tag); + + return 0; }
/* @@ -3315,7 +3320,9 @@ static blk_status_t mtip_queue_rq(struct blk_mq_hw_ctx *hctx,
blk_mq_start_request(rq);
- mtip_hw_submit_io(dd, rq, cmd, hctx); + if (mtip_hw_submit_io(dd, rq, cmd, hctx)) + return BLK_STS_IOERR; + return BLK_STS_OK; }