eal: fix memory mapping for 32-bit targets

For 32-bit targets, size_t is normally a 32-bit type and
does not have sufficient range to represent 64-bit offsets
that can are needed when mapping PCI addresses. Use off_t
instead, which is usually a 64-bit type when compiled with
_D_FILE_OFFSET_BITS=64 as is the case for DPDK.

Found when attempting to run 32-bit Linux dpdk-testpmd
using VFIO driver:

    EAL: pci_map_resource(): cannot map resource(63, 0xc0010000, \
    0x200000, 0x20000000000): Invalid argument ((nil))

Fixes: c4b89ecb64ea ("eal: introduce memory management wrappers")
Cc: stable@dpdk.org
Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
---
 lib/eal/include/rte_eal_paging.h |  2 +-
 lib/eal/unix/eal_unix_memory.c   | 10 +++++-----
 lib/eal/windows/eal_memory.c     |  2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

On Fri, May 7, 2021 at 2:10 PM Lance Richardson
<lance.richardson@broadcom.com> wrote:
>
> For 32-bit targets, size_t is normally a 32-bit type and
> does not have sufficient range to represent 64-bit offsets
> that can are needed when mapping PCI addresses. Use off_t
> instead, which is usually a 64-bit type when compiled with
> _D_FILE_OFFSET_BITS=64 as is the case for DPDK.
>
> Found when attempting to run 32-bit Linux dpdk-testpmd
> using VFIO driver:
>
>     EAL: pci_map_resource(): cannot map resource(63, 0xc0010000, \
>     0x200000, 0x20000000000): Invalid argument ((nil))
>
> Fixes: c4b89ecb64ea ("eal: introduce memory management wrappers")
> Cc: stable@dpdk.org
> Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
> ---
>  lib/eal/include/rte_eal_paging.h |  2 +-
>  lib/eal/unix/eal_unix_memory.c   | 10 +++++-----
>  lib/eal/windows/eal_memory.c     |  2 +-
>  3 files changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/lib/eal/include/rte_eal_paging.h b/lib/eal/include/rte_eal_paging.h
> index ed98e70e9e..2c05025ffc 100644
> --- a/lib/eal/include/rte_eal_paging.h
> +++ b/lib/eal/include/rte_eal_paging.h
> @@ -61,7 +61,7 @@ enum rte_map_flags {
>  __rte_internal
>  void *
>  rte_mem_map(void *requested_addr, size_t size, int prot, int flags,
> -       int fd, size_t offset);
> +       int fd, off_t offset);
>
>  /**
>   * OS-independent implementation of POSIX munmap(3).
> diff --git a/lib/eal/unix/eal_unix_memory.c b/lib/eal/unix/eal_unix_memory.c
> index ec7156df96..51a42e1a43 100644
> --- a/lib/eal/unix/eal_unix_memory.c
> +++ b/lib/eal/unix/eal_unix_memory.c
> @@ -24,14 +24,14 @@
>
>  static void *
>  mem_map(void *requested_addr, size_t size, int prot, int flags,
> -       int fd, size_t offset)
> +       int fd, off_t offset)
>  {
>         void *virt = mmap(requested_addr, size, prot, flags, fd, offset);
>         if (virt == MAP_FAILED) {
>                 RTE_LOG(DEBUG, EAL,
> -                       "Cannot mmap(%p, 0x%zx, 0x%x, 0x%x, %d, 0x%zx): %s\n",
> -                       requested_addr, size, prot, flags, fd, offset,
> -                       strerror(errno));
> +                       "Cannot mmap(%p, 0x%zx, 0x%x, 0x%x, %d, 0x%llx): %s\n",
> +                       requested_addr, size, prot, flags, fd,
> +                       (unsigned long long)offset, strerror(errno));
>                 rte_errno = errno;
>                 return NULL;
>         }
> @@ -106,7 +106,7 @@ mem_rte_to_sys_prot(int prot)
>
>  void *
>  rte_mem_map(void *requested_addr, size_t size, int prot, int flags,
> -       int fd, size_t offset)
> +       int fd, off_t offset)
>  {
>         int sys_flags = 0;
>         int sys_prot;
> diff --git a/lib/eal/windows/eal_memory.c b/lib/eal/windows/eal_memory.c
> index 2cf5a5e649..f1c4b03e96 100644
> --- a/lib/eal/windows/eal_memory.c
> +++ b/lib/eal/windows/eal_memory.c
> @@ -508,7 +508,7 @@ eal_mem_set_dump(void *virt, size_t size, bool dump)
>
>  void *
>  rte_mem_map(void *requested_addr, size_t size, int prot, int flags,
> -       int fd, size_t offset)
> +       int fd, off_t offset)
>  {
>         HANDLE file_handle = INVALID_HANDLE_VALUE;
>         HANDLE mapping_handle = INVALID_HANDLE_VALUE;
> --
> 2.25.1
>

Windows compilation is failing in CI, apparently Windows doesn't
understand "off_t".

Should we add an "rte_off_t" definition for non-POSIX portability?

> Windows compilation is failing in CI, apparently Windows doesn't
> understand "off_t".
>
> Should we add an "rte_off_t" definition for non-POSIX portability?

On second thought, it's probably better to simply use uint64_t.