Re: [PATCHv5 7/7] pciutils: Allow 32-bit domains

From: Martin Mares
Date: Sun Jan 03 2016 - 09:20:33 EST


Hello!

> PCI-e segments will continue to use the lower 16 bits as required by
> ACPI. Special domains may use the full 32-bits.
>
> Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
> ---
> lib/filter.c | 2 +-
> lib/pci.h | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/lib/filter.c b/lib/filter.c
> index d4254a0..075dc2f 100644
> --- a/lib/filter.c
> +++ b/lib/filter.c
> @@ -45,7 +45,7 @@ pci_filter_parse_slot_v33(struct pci_filter *f, char *str)
> if (str[0] && strcmp(str, "*"))
> {
> long int x = strtol(str, &e, 16);
> - if ((e && *e) || (x < 0 || x > 0xffff))
> + if ((e && *e) || (x < 0))
> return "Invalid domain number";
> f->domain = x;
> }
> diff --git a/lib/pci.h b/lib/pci.h
> index 10ba831..7e42765 100644
> --- a/lib/pci.h
> +++ b/lib/pci.h
> @@ -119,7 +119,7 @@ struct pci_param *pci_walk_params(struct pci_access *acc, struct pci_param *prev
>
> struct pci_dev {
> struct pci_dev *next; /* Next device in the chain */
> - u16 domain; /* PCI domain (host bridge) */
> + int32_t domain; /* PCI domain (host bridge) */
> u8 bus, dev, func; /* Bus inside domain, device and function */

This is definitely not enough. Try grepping the source for "domain" :-)

At least the following places need updating, too:

o struct pci_filter and operations on it

o Format strings for printing domains at various places

o ABI compability ... changing a field in the middle of struct pci_dev
(or pci_filter) is going to break ABI, so you either need to change the
structures in a backward-compatible way, or to use ABI versioning.

Also, we should decide on what type the domain should have -- currently, some
places use "int", others use u16, and your patch introduces int32_t. I would
prefer u32 myself, but especially in the filters we should be careful about
how to encode "any domain".

Have a nice new year
Martin
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