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author | Gerd Bayer <gbayer@linux.ibm.com> | 2024-04-05 14:16:06 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-04-17 12:23:29 +0300 |
commit | 94ad0fdb1f5a8eb3a53a79b6b241ea2e1d08919f (patch) | |
tree | 6373c679e3e715cd5ef1a93681a2f004c748bc2a /drivers/s390 | |
parent | 357163fff3a6e48fe74745425a32071ec9caf852 (diff) | |
download | linux-94ad0fdb1f5a8eb3a53a79b6b241ea2e1d08919f.tar.xz |
s390/ism: fix receive message buffer allocation
[ Upstream commit 58effa3476536215530c9ec4910ffc981613b413 ]
Since [1], dma_alloc_coherent() does not accept requests for GFP_COMP
anymore, even on archs that may be able to fulfill this. Functionality that
relied on the receive buffer being a compound page broke at that point:
The SMC-D protocol, that utilizes the ism device driver, passes receive
buffers to the splice processor in a struct splice_pipe_desc with a
single entry list of struct pages. As the buffer is no longer a compound
page, the splice processor now rejects requests to handle more than a
page worth of data.
Replace dma_alloc_coherent() and allocate a buffer with folio_alloc and
create a DMA map for it with dma_map_page(). Since only receive buffers
on ISM devices use DMA, qualify the mapping as FROM_DEVICE.
Since ISM devices are available on arch s390, only and on that arch all
DMA is coherent, there is no need to introduce and export some kind of
dma_sync_to_cpu() method to be called by the SMC-D protocol layer.
Analogously, replace dma_free_coherent by a two step dma_unmap_page,
then folio_put to free the receive buffer.
[1] https://lore.kernel.org/all/20221113163535.884299-1-hch@lst.de/
Fixes: c08004eede4b ("s390/ism: don't pass bogus GFP_ flags to dma_alloc_coherent")
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/s390')
-rw-r--r-- | drivers/s390/net/ism_drv.c | 38 |
1 files changed, 29 insertions, 9 deletions
diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c index 2c8e964425dc..affb05521e14 100644 --- a/drivers/s390/net/ism_drv.c +++ b/drivers/s390/net/ism_drv.c @@ -14,6 +14,8 @@ #include <linux/err.h> #include <linux/ctype.h> #include <linux/processor.h> +#include <linux/dma-mapping.h> +#include <linux/mm.h> #include "ism.h" @@ -292,13 +294,15 @@ out: static void ism_free_dmb(struct ism_dev *ism, struct ism_dmb *dmb) { clear_bit(dmb->sba_idx, ism->sba_bitmap); - dma_free_coherent(&ism->pdev->dev, dmb->dmb_len, - dmb->cpu_addr, dmb->dma_addr); + dma_unmap_page(&ism->pdev->dev, dmb->dma_addr, dmb->dmb_len, + DMA_FROM_DEVICE); + folio_put(virt_to_folio(dmb->cpu_addr)); } static int ism_alloc_dmb(struct ism_dev *ism, struct ism_dmb *dmb) { unsigned long bit; + int rc; if (PAGE_ALIGN(dmb->dmb_len) > dma_get_max_seg_size(&ism->pdev->dev)) return -EINVAL; @@ -315,14 +319,30 @@ static int ism_alloc_dmb(struct ism_dev *ism, struct ism_dmb *dmb) test_and_set_bit(dmb->sba_idx, ism->sba_bitmap)) return -EINVAL; - dmb->cpu_addr = dma_alloc_coherent(&ism->pdev->dev, dmb->dmb_len, - &dmb->dma_addr, - GFP_KERNEL | __GFP_NOWARN | - __GFP_NOMEMALLOC | __GFP_NORETRY); - if (!dmb->cpu_addr) - clear_bit(dmb->sba_idx, ism->sba_bitmap); + dmb->cpu_addr = + folio_address(folio_alloc(GFP_KERNEL | __GFP_NOWARN | + __GFP_NOMEMALLOC | __GFP_NORETRY, + get_order(dmb->dmb_len))); - return dmb->cpu_addr ? 0 : -ENOMEM; + if (!dmb->cpu_addr) { + rc = -ENOMEM; + goto out_bit; + } + dmb->dma_addr = dma_map_page(&ism->pdev->dev, + virt_to_page(dmb->cpu_addr), 0, + dmb->dmb_len, DMA_FROM_DEVICE); + if (dma_mapping_error(&ism->pdev->dev, dmb->dma_addr)) { + rc = -ENOMEM; + goto out_free; + } + + return 0; + +out_free: + kfree(dmb->cpu_addr); +out_bit: + clear_bit(dmb->sba_idx, ism->sba_bitmap); + return rc; } int ism_register_dmb(struct ism_dev *ism, struct ism_dmb *dmb, |