On Wed, Jul 02, 2014 at 01:38:04PM +0100, Arnd Bergmann wrote: > Some more detailed comments now > > On Tuesday 01 July 2014 19:43:28 Liviu Dudau wrote: > > +/* > > + * Record the PCI IO range (expressed as CPU physical address + size). > > + * Return a negative value if an error has occured, zero otherwise > > + */ > > +int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size) > > +{ > > +#ifdef PCI_IOBASE > > + struct io_range *res; > > I was confused by the variable naming here: A variable named 'res' is > normally a 'struct resource'. Maybe better call this 'range'. > > > + resource_size_t allocated_size = 0; > > + > > + /* check if the range hasn't been previously recorded */ > > + list_for_each_entry(res, &io_range_list, list) { > > + if (addr >= res->start && addr + size <= res->start + size) > > + return 0; > > + allocated_size += res->size; > > + } > > A spin_lock around the list lookup should be sufficient to get around > the race that Will mentioned. > > > + /* range not registed yet, check for available space */ > > + if (allocated_size + size - 1 > IO_SPACE_LIMIT) > > + return -E2BIG; > > It might be better to limit the size to 64K if it doesn't fit at first. Thanks Arnd for review. Will update and post a new patch soon if I don't get any other comments. Best regards, Liviu > > > Arnd > > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯ -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html