46a660444e
To optimize the case of ping-ponging between two buffers, the DDP code caches the last two buffers used keeping the pages wired and page pods stored in the NIC's RAM. If a new aio_read() request uses one of the same buffers, then the work of holding pages, etc. can be avoided. However, the starting virtual address of an aio buffer was not saved, only the page count, length, and initial page offset. Thus, an aio_read() request could match a different buffer in the address space. (Earlier during development vm_fault_hold_quick_pages() was always called and the vm_page_t values were compared, but that was eventually removed without being adequately replaced.) Fix by storing the starting virtual address and comparing that (along with other fields) to determine if a buffer can be reused. MFC after: 3 days Sponsored by: Chelsio Communications
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