Subject: [PATCH net,v2] net: mana: Switch to page pool for jumbo frames
Frag allocators, such as netdev_alloc_frag(), were not designed to work
for
fragsz > PAGE_SIZE.
So, switch to page pool for jumbo frames instead of using page frag
allocators.
This driver is using page pool for smaller MTUs already.
Cc: stable@vger.kernel.org Fixes: 80f6215b450e ("net: mana: Add support for jumbo frame") Signed-off-by: Haiyang Zhang haiyangz@microsoft.com
Reviewed-by: Long Li longli@microsoft.com
v2: updated the commit msg as suggested by Jakub Kicinski.
drivers/net/ethernet/microsoft/mana/mana_en.c | 46 ++++--------------- 1 file changed, 9 insertions(+), 37 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index 9a8171f099b6..4d41f4cca3d8 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -661,30 +661,16 @@ int mana_pre_alloc_rxbufs(struct mana_port_context *mpc, int new_mtu, int num_qu mpc->rxbpre_total = 0;
for (i = 0; i < num_rxb; i++) {
if (mpc->rxbpre_alloc_size > PAGE_SIZE) {va = netdev_alloc_frag(mpc->rxbpre_alloc_size);if (!va)goto error;page = virt_to_head_page(va);/* Check if the frag falls back to single page */if (compound_order(page) <get_order(mpc->rxbpre_alloc_size)) {put_page(page);goto error;}} else {page = dev_alloc_page();if (!page)goto error;
page = dev_alloc_pages(get_order(mpc->rxbpre_alloc_size));if (!page)goto error;
va = page_to_virt(page);}
va = page_to_virt(page); da = dma_map_single(dev, va + mpc->rxbpre_headroom, mpc->rxbpre_datasize, DMA_FROM_DEVICE); if (dma_mapping_error(dev, da)) {
put_page(virt_to_head_page(va));
put_page(page);Should we use __free_pages()?
Quote from doc: https://www.ker/ nel.org%2Fdoc%2Fhtml%2Fnext%2Fcore-api%2Fmm- api.html&data=05%7C02%7Clongli%40microsoft.com%7Cada2b7bad76e4ab7286 508dd6bc87430%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C638785 230869082534%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIl YiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C 0%7C%7C%7C&sdata=VINKfrv80MzhE1mmibv1RrRz4WCmr%2BZhWDf1ZaOv47 w%3D&reserved=0 ___free_pages(): "This function can free multi-page allocations that are not compound pages." "If you want to use the page's reference count to decide when to free the allocation, you should allocate a compound page, and use put_page() instead of __free_pages()."
And, since dev_alloc_pages returns compound page for high order page, we use put_page() which works for both compound & single page.
Thanks,
- Haiyang