Blame SOURCES/kvm-block-backend-align-max_transfer-to-request-alignmen.patch

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From 643c979c2bfa0fc3c45ec8ec5f05a77e0b075356 Mon Sep 17 00:00:00 2001
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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Fri, 16 Jul 2021 16:51:32 -0400
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Subject: [PATCH 16/43] block-backend: align max_transfer to request alignment
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RH-Author: Miroslav Rezanina <mrezanin@redhat.com>
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RH-Bugzilla: 1957194
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Block device requests must be aligned to bs->bl.request_alignment.
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It makes sense for drivers to align bs->bl.max_transfer the same
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way; however when there is no specified limit, blk_get_max_transfer
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just returns INT_MAX.  Since the contract of the function does not
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specify that INT_MAX means "no maximum", just align the outcome
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of the function (whether INT_MAX or bs->bl.max_transfer) before
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returning it.
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Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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(cherry picked from commit b99f7fa08a3df8b8a6a907642e5851cdcf43fa9f)
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Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 block/block-backend.c | 6 +++---
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 1 file changed, 3 insertions(+), 3 deletions(-)
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diff --git a/block/block-backend.c b/block/block-backend.c
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index 05d8e5fb5d..136cc602c5 100644
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--- a/block/block-backend.c
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+++ b/block/block-backend.c
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@@ -1943,12 +1943,12 @@ uint32_t blk_get_request_alignment(BlockBackend *blk)
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 uint32_t blk_get_max_transfer(BlockBackend *blk)
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 {
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     BlockDriverState *bs = blk_bs(blk);
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-    uint32_t max = 0;
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+    uint32_t max = INT_MAX;
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     if (bs) {
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-        max = bs->bl.max_transfer;
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+        max = MIN_NON_ZERO(max, bs->bl.max_transfer);
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     }
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-    return MIN_NON_ZERO(max, INT_MAX);
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+    return ROUND_DOWN(max, blk_get_request_alignment(blk));
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 }
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 int blk_get_max_iov(BlockBackend *blk)
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-- 
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2.27.0
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