> From: Shijith Thotton [mailto:sthot...@marvell.com]
> Sent: Monday, 29 August 2022 17.16
>
> IOVA mode in DPDK is either PA or VA. The new build option iova_as_va
> configures the mode to VA at compile time and prevents setting it to PA
> at runtime. For now, all drivers which are not always enabled are
> disabled with this option. Supported driver can set the flag
> pmd_iova_as_va in its build file to enable build.
>
> mbuf structure holds the physical (PA) and virtual address (VA) of a
> buffer. if IOVA mode is set to VA, PA is redundant as it is the same as
> VA. So PA field need not be updated and marked invalid if the build is
> configured to use only VA.
>
> Signed-off-by: Shijith Thotton <sthot...@marvell.com>
> ---
[...]
> diff --git a/app/test/test_mbuf.c b/app/test/test_mbuf.c
> index e09b2549ca..992b8c64ab 100644
> --- a/app/test/test_mbuf.c
> +++ b/app/test/test_mbuf.c
> @@ -1232,11 +1232,13 @@ test_failing_mbuf_sanity_check(struct
> rte_mempool *pktmbuf_pool)
> return -1;
> }
>
> - badbuf = *buf;
> - badbuf.buf_iova = 0;
> - if (verify_mbuf_check_panics(&badbuf)) {
> - printf("Error with bad-physaddr mbuf test\n");
> - return -1;
> + if (!rte_is_iova_as_va_build()) {
> + badbuf = *buf;
> + rte_mbuf_iova_set(&badbuf, 0);
> + if (verify_mbuf_check_panics(&badbuf)) {
> + printf("Error with bad-physaddr mbuf test\n");
> + return -1;
> + }
> }
>
> badbuf = *buf;
> diff --git a/config/meson.build b/config/meson.build
> index 7f7b6c92fd..1ff1cd774b 100644
> --- a/config/meson.build
> +++ b/config/meson.build
> @@ -309,6 +309,9 @@ endif
> if get_option('mbuf_refcnt_atomic')
> dpdk_conf.set('RTE_MBUF_REFCNT_ATOMIC', true)
> endif
> +if get_option('iova_as_va')
> + dpdk_conf.set('RTE_IOVA_AS_VA', true)
> +endif
>
> compile_time_cpuflags = []
> subdir(arch_subdir)
> diff --git a/drivers/meson.build b/drivers/meson.build
> index b22c2adda7..469e60f1fa 100644
> --- a/drivers/meson.build
> +++ b/drivers/meson.build
> @@ -103,6 +103,7 @@ foreach subpath:subdirs
> ext_deps = []
> pkgconfig_extra_libs = []
> testpmd_sources = []
> + pmd_iova_as_va = false
>
> if not enable_drivers.contains(drv_path)
> build = false
> @@ -120,6 +121,11 @@ foreach subpath:subdirs
> # pull in driver directory which should update all the
> local variables
> subdir(drv_path)
>
> + if dpdk_conf.has('RTE_IOVA_AS_VA') and not pmd_iova_as_va
> and not always_enable.contains(drv_path)
> + build = false
> + reason = 'driver does not support IOVA as VA mode'
> + endif
> +
> # get dependency objs from strings
> shared_deps = ext_deps
> static_deps = ext_deps
> diff --git a/lib/eal/include/rte_common.h
> b/lib/eal/include/rte_common.h
> index a96cc2a138..0010ad7c7d 100644
> --- a/lib/eal/include/rte_common.h
> +++ b/lib/eal/include/rte_common.h
> @@ -921,6 +921,23 @@ __rte_noreturn void
> rte_exit(int exit_code, const char *format, ...)
> __rte_format_printf(2, 3);
>
> +/**
> + * Check if build is configured to use IOVA as VA.
> + *
> + * @return
> + * 1 if true, 0 otherwise
> + *
> + */
> +static inline int
> +rte_is_iova_as_va_build(void)
> +{
> +#ifdef RTE_IOVA_AS_VA
> + return 1;
> +#else
> + return 0;
> +#endif
> +}
The rte_is_iova_as_va_build() function is effectively a shadow of the
RTE_IOVA_AS_VA definition. Why the need to camouflage RTE_IOVA_AS_VA through a
function, instead of just using RTE_IOVA_AS_VA everywhere?
