Use the scatterlist memory iterator instead of just dereferencing virtual memory using sg_virt(). This make highmem references work properly. Suggested-by: Christoph Hellwig <hch@xxxxxx> Link: https://lore.kernel.org/linux-mmc/20240122073423.GA25859@xxxxxx/ Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> --- drivers/mmc/host/moxart-mmc.c | 77 +++++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 43 deletions(-) diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c index 8ede4ce93271..b88d6dec209f 100644 --- a/drivers/mmc/host/moxart-mmc.c +++ b/drivers/mmc/host/moxart-mmc.c @@ -131,12 +131,10 @@ struct moxart_host { struct dma_async_tx_descriptor *tx_desc; struct mmc_host *mmc; struct mmc_request *mrq; - struct scatterlist *cur_sg; struct completion dma_complete; struct completion pio_complete; - u32 num_sg; - u32 data_remain; + struct sg_mapping_iter sg_miter; u32 data_len; u32 fifo_width; u32 timeout; @@ -148,35 +146,6 @@ struct moxart_host { bool is_removed; }; -static inline void moxart_init_sg(struct moxart_host *host, - struct mmc_data *data) -{ - host->cur_sg = data->sg; - host->num_sg = data->sg_len; - host->data_remain = host->cur_sg->length; - - if (host->data_remain > host->data_len) - host->data_remain = host->data_len; -} - -static inline int moxart_next_sg(struct moxart_host *host) -{ - int remain; - struct mmc_data *data = host->mrq->cmd->data; - - host->cur_sg++; - host->num_sg--; - - if (host->num_sg > 0) { - host->data_remain = host->cur_sg->length; - remain = host->data_len - data->bytes_xfered; - if (remain > 0 && remain < host->data_remain) - host->data_remain = remain; - } - - return host->num_sg; -} - static int moxart_wait_for_status(struct moxart_host *host, u32 mask, u32 *status) { @@ -309,14 +278,28 @@ static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host) static void moxart_transfer_pio(struct moxart_host *host) { + struct sg_mapping_iter *sgm = &host->sg_miter; struct mmc_data *data = host->mrq->cmd->data; u32 *sgp, len = 0, remain, status; if (host->data_len == data->bytes_xfered) return; - sgp = sg_virt(host->cur_sg); - remain = host->data_remain; + /* + * By updating sgm->consumes this will get a proper pointer into the + * buffer at any time. + */ + if (!sg_miter_next(sgm)) { + /* This shold not happen */ + dev_err(mmc_dev(host->mmc), "ran out of scatterlist prematurely\n"); + data->error = -EINVAL; + complete(&host->pio_complete); + return; + } + sgp = sgm->addr; + remain = sgm->length; + if (remain > host->data_len) + remain = host->data_len; if (data->flags & MMC_DATA_WRITE) { while (remain > 0) { @@ -331,6 +314,7 @@ static void moxart_transfer_pio(struct moxart_host *host) sgp++; len += 4; } + sgm->consumed += len; remain -= len; } @@ -347,22 +331,22 @@ static void moxart_transfer_pio(struct moxart_host *host) sgp++; len += 4; } + sgm->consumed += len; remain -= len; } } - data->bytes_xfered += host->data_remain - remain; - host->data_remain = remain; - - if (host->data_len != data->bytes_xfered) - moxart_next_sg(host); - else + data->bytes_xfered += sgm->consumed; + if (host->data_len == data->bytes_xfered) { complete(&host->pio_complete); + return; + } } static void moxart_prepare_data(struct moxart_host *host) { struct mmc_data *data = host->mrq->cmd->data; + unsigned int flags = SG_MITER_ATOMIC; /* Used from IRQ */ u32 datactrl; int blksz_bits; @@ -373,15 +357,19 @@ static void moxart_prepare_data(struct moxart_host *host) blksz_bits = ffs(data->blksz) - 1; BUG_ON(1 << blksz_bits != data->blksz); - moxart_init_sg(host, data); - datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE); - if (data->flags & MMC_DATA_WRITE) + if (data->flags & MMC_DATA_WRITE) { + flags |= SG_MITER_FROM_SG; datactrl |= DCR_DATA_WRITE; + } else { + flags |= SG_MITER_TO_SG; + } if (moxart_use_dma(host)) datactrl |= DCR_DMA_EN; + else + sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags); writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL); writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR); @@ -454,6 +442,9 @@ static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq) } request_done: + if (!moxart_use_dma(host)) + sg_miter_stop(&host->sg_miter); + spin_unlock_irqrestore(&host->lock, flags); mmc_request_done(host->mmc, mrq); } -- 2.34.1
