[PATCH v3 2/5] PCI: Cleanup comments in setup-bus.c to meet kernel coding style guidelines

From: Nicholas Johnson
Date: Mon Apr 15 2019 - 13:09:43 EST


Change block comments to accepted style with asterisks on each line.

Justify block comments to 80-character limit to reduce the number of
lines where possible.

Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@xxxxxxxxxxxxxx>
---
drivers/pci/setup-bus.c | 265 ++++++++++++++++++++--------------------
1 file changed, 130 insertions(+), 135 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 75827fb06..0ce641282 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -51,11 +51,9 @@ static void free_list(struct list_head *head)
/**
* add_to_list() - add a new resource tracker to the list
* @head: Head of the list
- * @dev: device corresponding to which the resource
- * belongs
+ * @dev: device corresponding to which the resource belongs
* @res: The resource to be tracked
- * @add_size: additional size to be optionally added
- * to the resource
+ * @add_size: additional size to be optionally added to the resource
*/
static int add_to_list(struct list_head *head,
struct pci_dev *dev, struct resource *res,
@@ -158,7 +156,7 @@ static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head)
tmp->res = r;
tmp->dev = dev;

- /* fallback is smallest one or list is empty*/
+ /* fallback is smallest one or list is empty */
n = head;
list_for_each_entry(dev_res, head, list) {
resource_size_t align;
@@ -171,7 +169,7 @@ static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head)
break;
}
}
- /* Insert it just before n*/
+ /* Insert it just before n */
list_add_tail(&tmp->list, n);
}
}
@@ -181,7 +179,7 @@ static void __dev_sort_resources(struct pci_dev *dev,
{
u16 class = dev->class >> 8;

- /* Don't touch classless devices or host bridges or ioapics. */
+ /* Don't touch classless devices or host bridges or ioapics */
if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
return;

@@ -208,12 +206,10 @@ static inline void reset_resource(struct resource *res)
*
* @realloc_head : head of the list tracking requests requiring additional
* resources
- * @head : head of the list tracking requests with allocated
- * resources
+ * @head : head of the list tracking requests with allocated resources
*
- * Walk through each element of the realloc_head and try to procure
- * additional resources for the element, provided the element
- * is in the head list.
+ * Walk through each element of the realloc_head and try to procure additional
+ * resources for the element, provided the element is in the head list.
*/
static void reassign_resources_sorted(struct list_head *realloc_head,
struct list_head *head)
@@ -315,10 +311,9 @@ static unsigned long pci_fail_res_type_mask(struct list_head *fail_head)
mask |= fail_res->flags;

/*
- * one pref failed resource will set IORESOURCE_MEM,
- * as we can allocate pref in non-pref range.
- * Will release all assigned non-pref sibling resources
- * according to that bit.
+ * one pref failed resource will set IORESOURCE_MEM, as we can allocate
+ * pref in non-pref range. Will release all assigned non-pref sibling
+ * resources according to that bit.
*/
return mask & (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH);
}
@@ -351,25 +346,24 @@ static void __assign_resources_sorted(struct list_head *head,
struct list_head *fail_head)
{
/*
- * Should not assign requested resources at first.
- * they could be adjacent, so later reassign can not reallocate
- * them one by one in parent resource window.
- * Try to assign requested + add_size at beginning
- * if could do that, could get out early.
- * if could not do that, we still try to assign requested at first,
- * then try to reassign add_size for some resources.
+ * Should not assign requested resources at first. They could be
+ * adjacent, so later reassign can not reallocate them one by one in
+ * parent resource window.
+ *
+ * Try to assign requested + add_size at beginning. If could do that,
+ * could get out early. If could not do that, we still try to assign
+ * requested at first, then try to reassign add_size for some resources.
*
* Separate three resource type checking if we need to release
* assigned resource after requested + add_size try.
- * 1. if there is io port assign fail, will release assigned
- * io port.
- * 2. if there is pref mmio assign fail, release assigned
- * pref mmio.
- * if assigned pref mmio's parent is non-pref mmio and there
- * is non-pref mmio assign fail, will release that assigned
- * pref mmio.
- * 3. if there is non-pref mmio assign fail or pref mmio
- * assigned fail, will release assigned non-pref mmio.
+ * 1. if there is io port assign fail, will release assigned io
+ * port.
+ * 2. if there is pref mmio assign fail, release assigned pref
+ * mmio. If assigned pref mmio's parent is non-pref mmio
+ * and there is non-pref mmio assign fail, will release that
+ * assigned pref mmio.
+ * 3. if there is non-pref mmio assign fail or pref mmio assigned
+ * fail, will release assigned non-pref mmio.
*/
LIST_HEAD(save_head);
LIST_HEAD(local_fail_head);
@@ -398,7 +392,7 @@ static void __assign_resources_sorted(struct list_head *head,
/*
* There are two kinds of additional resources in the list:
* 1. bridge resource -- IORESOURCE_STARTALIGN
- * 2. SR-IOV resource -- IORESOURCE_SIZEALIGN
+ * 2. SR-IOV resource -- IORESOURCE_SIZEALIGN
* Here just fix the additional alignment for bridge
*/
if (!(dev_res->res->flags & IORESOURCE_STARTALIGN))
@@ -477,8 +471,7 @@ static void __assign_resources_sorted(struct list_head *head,
/* Satisfy the must-have resource requests */
assign_requested_resources_sorted(head, fail_head);

- /* Try to satisfy any additional optional resource
- requests */
+ /* Try to satisfy any additional optional resource requests */
if (realloc_head)
reassign_resources_sorted(realloc_head, head);
free_list(head);
@@ -563,17 +556,19 @@ void pci_setup_cardbus(struct pci_bus *bus)
}
EXPORT_SYMBOL(pci_setup_cardbus);

-/* Initialize bridges with base/limit values we have collected.
- PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
- requires that if there is no I/O ports or memory behind the
- bridge, corresponding range must be turned off by writing base
- value greater than limit to the bridge's base/limit registers.
-
- Note: care must be taken when updating I/O base/limit registers
- of bridges which support 32-bit I/O. This update requires two
- config space writes, so it's quite possible that an I/O window of
- the bridge will have some undesirable address (e.g. 0) after the
- first write. Ditto 64-bit prefetchable MMIO. */
+/*
+ * Initialize bridges with base/limit values we have collected. PCI-to-PCI
+ * Bridge Architecture Specification rev. 1.1 (1998) requires that if there is
+ * no I/O ports or memory behind the bridge, corresponding range must be turned
+ * off by writing base value greater than limit to the bridge's base/limit
+ * registers.
+ *
+ * Note: care must be taken when updating I/O base/limit registers of bridges
+ * which support 32-bit I/O. This update requires two config space writes, so
+ * it's quite possible that an I/O window of the bridge will have some
+ * undesirable address (e.g. 0) after the first write. Ditto 64-bit prefetchable
+ * MMIO.
+ */
static void pci_setup_bridge_io(struct pci_dev *bridge)
{
struct resource *res;
@@ -636,9 +631,11 @@ static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge)
struct pci_bus_region region;
u32 l, bu, lu;

- /* Clear out the upper 32 bits of PREF limit.
- If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
- disables PREF range, which is ok. */
+ /*
+ * Clear out the upper 32 bits of PREF limit.
+ * If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
+ * disables PREF range, which is ok.
+ */
pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);

/* Set up PREF base/limit. */
@@ -730,9 +727,11 @@ int pci_claim_bridge_resource(struct pci_dev *bridge, int i)
return -EINVAL;
}

-/* Check whether the bridge supports optional I/O and
- prefetchable memory ranges. If not, the respective
- base/limit registers must be read-only and read as 0. */
+/*
+ * Check whether the bridge supports optional I/O and prefetchable memory
+ * ranges. If not, the respective base/limit registers must be read-only and
+ * read as 0.
+ */
static void pci_bridge_check_ranges(struct pci_bus *bus)
{
u16 io;
@@ -752,9 +751,11 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)
if (io)
b_res[0].flags |= IORESOURCE_IO;

- /* DECchip 21050 pass 2 errata: the bridge may miss an address
- disconnect boundary by one PCI data phase.
- Workaround: do not use prefetching on this device. */
+ /*
+ * DECchip 21050 pass 2 errata: the bridge may miss an address
+ * disconnect boundary by one PCI data phase. Workaround: do not use
+ * prefetching on this device.
+ */
if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
return;

@@ -789,10 +790,11 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)
}
}

-/* Helper function for sizing routines: find first available
- bus resource of a given type. Note: we intentionally skip
- the bus resources which have already been assigned (that is,
- have non-NULL parent resource). */
+/*
+ * Helper function for sizing routines: find first available bus resource of a
+ * given type. Note: we intentionally skip the bus resources which have already
+ * been assigned (that is, have non-NULL parent resource).
+ */
static struct resource *find_free_bus_resource(struct pci_bus *bus,
unsigned long type_mask, unsigned long type)
{
@@ -820,8 +822,10 @@ static resource_size_t calculate_iosize(resource_size_t size,
size = min_size;
if (old_size == 1)
old_size = 0;
- /* To be fixed in 2.5: we should have sort of HAVE_ISA
- flag in the struct pci_bus. */
+ /*
+ * To be fixed in 2.5: we should have sort of HAVE_ISA flag in the
+ * struct pci_bus.
+ */
#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
size = (size & 0xff) + ((size & ~0xffUL) << 2);
#endif
@@ -870,8 +874,8 @@ static resource_size_t window_alignment(struct pci_bus *bus,
align = PCI_P2P_DEFAULT_MEM_ALIGN;
else if (type & IORESOURCE_IO) {
/*
- * Per spec, I/O windows are 4K-aligned, but some
- * bridges have an extension to support 1K alignment.
+ * Per spec, I/O windows are 4K-aligned, but some bridges have
+ * an extension to support 1K alignment.
*/
if (bus->self->io_window_1k)
align = PCI_P2P_DEFAULT_IO_ALIGN_1K;
@@ -891,10 +895,9 @@ static resource_size_t window_alignment(struct pci_bus *bus,
* @add_size : additional optional io window
* @realloc_head : track the additional io window on this list
*
- * Sizing the IO windows of the PCI-PCI bridge is trivial,
- * since these windows have 1K or 4K granularity and the IO ranges
- * of non-bridge PCI devices are limited to 256 bytes.
- * We must be careful with the ISA aliasing though.
+ * Sizing the IO windows of the PCI-PCI bridge is trivial, since these windows
+ * have 1K or 4K granularity and the IO ranges of non-bridge PCI devices are
+ * limited to 256 bytes. We must be careful with the ISA aliasing though.
*/
static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
resource_size_t add_size, struct list_head *realloc_head)
@@ -995,12 +998,12 @@ static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
* @add_size : additional optional memory window
* @realloc_head : track the additional memory window on this list
*
- * Calculate the size of the bus and minimal alignment which
- * guarantees that all child resources fit in this size.
+ * Calculate the size of the bus and minimal alignment which guarantees that all
+ * child resources fit in this size.
*
* Returns -ENOSPC if there's no available bus resource of the desired type.
- * Otherwise, sets the bus resource start/end to indicate the required
- * size, adds things to realloc_head (if supplied), and returns 0.
+ * Otherwise, sets the bus resource start/end to indicate the required size,
+ * adds things to realloc_head (if supplied), and returns 0.
*/
static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
unsigned long type, unsigned long type2,
@@ -1010,7 +1013,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
{
struct pci_dev *dev;
resource_size_t min_align, align, size, size0, size1;
- resource_size_t aligns[18]; /* Alignments from 1Mb to 128Gb */
+ resource_size_t aligns[18]; /* Alignments from 1Mb to 128Gb */
int order, max_order;
struct resource *b_res = find_free_bus_resource(bus,
mask | IORESOURCE_PREFETCH, type);
@@ -1050,10 +1053,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
}
#endif
/*
- * aligns[0] is for 1MB (since bridge memory
- * windows are always at least 1MB aligned), so
- * keep "order" from being negative for smaller
- * resources.
+ * aligns[0] is for 1MB (since bridge memory windows are
+ * always at least 1MB aligned), so keep "order" from
+ * being negative for smaller resources.
*/
align = pci_resource_alignment(dev, r);
order = __ffs(align) - 20;
@@ -1066,8 +1068,10 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
continue;
}
size += max(r_size, align);
- /* Exclude ranges with size > align from
- calculation of the alignment. */
+ /*
+ * Exclude ranges with size > align from calculation of
+ * the alignment.
+ */
if (r_size <= align)
aligns[order] += align;
if (order > max_order)
@@ -1128,8 +1132,8 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
if (b_res[0].parent)
goto handle_b_res_1;
/*
- * Reserve some resources for CardBus. We reserve
- * a fixed amount of bus space for CardBus bridges.
+ * Reserve some resources for CardBus. We reserve a fixed amount of bus
+ * space for CardBus bridges.
*/
b_res[0].start = pci_cardbus_io_size;
b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1;
@@ -1161,10 +1165,7 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
}

- /*
- * Check whether prefetchable memory is supported
- * by this bridge.
- */
+ /* Check whether prefetchable memory is supported by this bridge. */
pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
@@ -1175,9 +1176,8 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
if (b_res[2].parent)
goto handle_b_res_3;
/*
- * If we have prefetchable memory support, allocate
- * two regions. Otherwise, allocate one region of
- * twice the size.
+ * If we have prefetchable memory support, allocate two regions.
+ * Otherwise, allocate one region of twice the size.
*/
if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
b_res[2].start = pci_cardbus_mem_size;
@@ -1256,9 +1256,8 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
additional_io_size, realloc_head);

/*
- * If there's a 64-bit prefetchable MMIO window, compute
- * the size required to put all 64-bit prefetchable
- * resources in it.
+ * If there's a 64-bit prefetchable MMIO window, compute the
+ * size required to put all 64-bit prefetchable resources in it.
*/
b_res = &bus->self->resource[PCI_BRIDGE_RESOURCES];
mask = IORESOURCE_MEM;
@@ -1271,9 +1270,9 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
additional_mem_size, realloc_head);

/*
- * If successful, all non-prefetchable resources
- * and any 32-bit prefetchable resources will go in
- * the non-prefetchable window.
+ * If successful, all non-prefetchable resources and any
+ * 32-bit prefetchable resources will go in the
+ * non-prefetchable window.
*/
if (ret == 0) {
mask = prefmask;
@@ -1308,18 +1307,17 @@ void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)

/*
* Compute the size required to put everything else in the
- * non-prefetchable window. This includes:
+ * non-prefetchable window. This includes:
*
* - all non-prefetchable resources
* - 32-bit prefetchable resources if there's a 64-bit
* prefetchable window or no prefetchable window at all
- * - 64-bit prefetchable resources if there's no
- * prefetchable window at all
+ * - 64-bit prefetchable resources if there's no prefetchable
+ * window at all
*
- * Note that the strategy in __pci_assign_resource() must
- * match that used here. Specifically, we cannot put a
- * 32-bit prefetchable resource in a 64-bit prefetchable
- * window.
+ * Note that the strategy in __pci_assign_resource() must match
+ * that used here. Specifically, we cannot put a 32-bit
+ * prefetchable resource in a 64-bit prefetchable window.
*/
pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3,
realloc_head ? 0 : additional_mem_size,
@@ -1352,8 +1350,8 @@ static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r)
}

/*
- * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they
- * are skipped by pbus_assign_resources_sorted().
+ * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they are
+ * skipped by pbus_assign_resources_sorted().
*/
static void pdev_assign_fixed_resources(struct pci_dev *dev)
{
@@ -1464,10 +1462,9 @@ static void pci_bus_allocate_resources(struct pci_bus *b)
struct pci_bus *child;

/*
- * Carry out a depth-first search on the PCI bus
- * tree to allocate bridge apertures. Read the
- * programmed bridge bases and recursively claim
- * the respective bridge resources.
+ * Carry out a depth-first search on the PCI bus tree to allocate bridge
+ * apertures. Read the programmed bridge bases and recursively claim the
+ * respective bridge resources.
*/
if (b->self) {
pci_read_bridge_bases(b);
@@ -1532,16 +1529,15 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
b_res = &dev->resource[PCI_BRIDGE_RESOURCES];

/*
- * 1. if there is io port assign fail, will release bridge
- * io port.
- * 2. if there is non pref mmio assign fail, release bridge
- * nonpref mmio.
- * 3. if there is 64bit pref mmio assign fail, and bridge pref
- * is 64bit, release bridge pref mmio.
- * 4. if there is pref mmio assign fail, and bridge pref is
- * 32bit mmio, release bridge pref mmio
- * 5. if there is pref mmio assign fail, and bridge pref is not
- * assigned, release bridge nonpref mmio.
+ * 1. if there is io port assign fail, will release bridge io port.
+ * 2. if there is non pref mmio assign fail, release bridge nonpref
+ * mmio.
+ * 3. if there is 64bit pref mmio assign fail, and bridge pref is 64bit,
+ * release bridge pref mmio.
+ * 4. if there is pref mmio assign fail, and bridge pref is 32bit mmio,
+ * release bridge pref mmio
+ * 5. if there is pref mmio assign fail, and bridge pref is not
+ * assigned, release bridge nonpref mmio.
*/
if (type & IORESOURCE_IO)
idx = 0;
@@ -1561,10 +1557,7 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
if (!r->parent)
return;

- /*
- * if there are children under that, we should release them
- * all
- */
+ /* if there are children under that, we should release them all */
release_child_resources(r);
if (!release_resource(r)) {
type = old_flags = r->flags & PCI_RES_TYPE_MASK;
@@ -1589,8 +1582,8 @@ enum release_type {
whole_subtree,
};
/*
- * try to release pci bridge resources that is from leaf bridge,
- * so we can allocate big new one later
+ * try to release pci bridge resources that is from leaf bridge, so we can
+ * allocate big new one later
*/
static void pci_bus_release_bridge_resources(struct pci_bus *bus,
unsigned long type,
@@ -1751,8 +1744,8 @@ static enum enable_type pci_realloc_detect(struct pci_bus *bus,
*/
void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus)
{
- LIST_HEAD(realloc_head); /* list of resources that
- want additional resources */
+ LIST_HEAD(realloc_head);
+ /* list of resources that want additional resources */
struct list_head *add_list = NULL;
int tried_times = 0;
enum release_type rel_type = leaf_only;
@@ -1774,13 +1767,14 @@ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus)

again:
/*
- * last try will use add_list, otherwise will try good to have as
- * must have, so can realloc parent bridge resource
+ * last try will use add_list, otherwise will try good to have as must
+ * have, so can realloc parent bridge resource
*/
if (tried_times + 1 == pci_try_num)
add_list = &realloc_head;
- /* Depth first, calculate sizes and alignments of all
- subordinate buses. */
+ /*
+ * Depth first, calculate sizes and alignments of all subordinate buses.
+ */
__pci_bus_size_bridges(bus, add_list);

/* Depth last, allocate resources and update the hardware. */
@@ -2040,8 +2034,9 @@ pci_bridge_distribute_available_resources(struct pci_dev *bridge,
void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
{
struct pci_bus *parent = bridge->subordinate;
- LIST_HEAD(add_list); /* list of resources that
- want additional resources */
+ /* list of resources that want additional resources */
+ LIST_HEAD(add_list);
+
int tried_times = 0;
LIST_HEAD(fail_head);
struct pci_dev_resource *fail_res;
@@ -2051,9 +2046,9 @@ void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
__pci_bus_size_bridges(parent, &add_list);

/*
- * Distribute remaining resources (if any) equally between
- * hotplug bridges below. This makes it possible to extend the
- * hierarchy later without running out of resources.
+ * Distribute remaining resources (if any) equally between hotplug
+ * bridges below. This makes it possible to extend the hierarchy
+ * later without running out of resources.
*/
pci_bridge_distribute_available_resources(bridge, &add_list);

@@ -2205,8 +2200,8 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type)
void pci_assign_unassigned_bus_resources(struct pci_bus *bus)
{
struct pci_dev *dev;
- LIST_HEAD(add_list); /* list of resources that
- want additional resources */
+ /* list of resources that want additional resources */
+ LIST_HEAD(add_list);

down_read(&pci_bus_sem);
for_each_pci_bridge(dev, bus)
--
2.20.1