From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Subject: Re: [PATCH v2 6/7] eal: pci: export pci_map_device
Date: Tue, 12 Jan 2016 16:40:43 +0800
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To: David Marchand <david.marchand@6wind.com>
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On Tue, Jan 12, 2016 at 09:31:05AM +0100, David Marchand wrote:
> On Tue, Jan 12, 2016 at 7:59 AM, Yuanhan Liu <yuanhan.liu@linux.intel.c=
om>
> wrote:
>=20
>     Normally we could set RTE_PCI_DRV_NEED_MAPPING flag so that eal wil=
l
>     invoke pci_map_device internally for us. From that point view, ther=
e
>     is no need to export pci_map_device.
>=20
>     However, for virtio pmd driver, which is designed to work without
>     binding UIO (or something similar first), pci_map_device() will fai=
l,
>     which ends up with virtio pmd driver being skipped. Therefore, we c=
an
>     not set RTE_PCI_DRV_NEED_MAPPING blindly at virtio pmd driver.
>=20
>     Therefore, this patch exports pci_map_device, and let virtio pmd
>     call it when necessary.
>=20
>=20
> Well, if you introduce map function, I suppose, for hotplug, you would =
need
> unmap.

Good remind. Thanks. I will export pci_unmap_device as well.

> [snip]
>=20
>=20
>     diff --git a/lib/librte_eal/common/include/rte_pci.h b/lib/librte_e=
al/
>     common/include/rte_pci.h
>     index 334c12e..e9e1725 100644
>     --- a/lib/librte_eal/common/include/rte_pci.h
>     +++ b/lib/librte_eal/common/include/rte_pci.h
>     @@ -485,6 +485,17 @@ int rte_eal_pci_read_config(const struct
>     rte_pci_device *device,
>     =A0 */
>     =A0int rte_eal_pci_write_config(const struct rte_pci_device *device=
,
>     =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0const vo=
id *buf, size_t len, off_t offset);
>     +/**
>     + * Map this device
>     + *
>     + * This function is private to EAL.
>     + *
>     + * @return
>     + *=A0 =A00 on success, negative on error and positive if no driver
>     + *=A0 =A0is found for the device.
>     + */
>     +int rte_eal_pci_map_device(struct rte_pci_device *dev);
>     +
>=20
>=20
> If you export it, then this can not be marked as private anymore.

Oops, a silly C&P error. Will fix it.

> Description could be better (I agree it was not that great before).
> And a little comment on when to call: driver should not set
> RTE_PCI_DRV_NEED_MAPPING flag if it wants to use it.

Good suggestion.

> The rest looks good to me.

Thanks.

	--yliu