| Message ID | 20160526085638.GF19428@n2100.arm.linux.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, May 26, 2016 at 2:26 PM, Russell King - ARM Linux <linux@armlinux.org.uk> wrote: > On Wed, May 25, 2016 at 01:30:44PM +0530, Pratyush Anand wrote: >> On Tue, May 3, 2016 at 3:52 PM, Russell King <rmk@arm.linux.org.uk> wrote: >> > +int mem_regions_exclude(struct memory_ranges *ranges, >> > + const struct memory_range *range) >> > +{ >> > + int i; >> > + >> > + for (i = 0; i < ranges->size; i++) { >> > + struct memory_range *r = ranges->ranges + i; >> > + >> > + /* >> > + * We assume that crash area is fully contained in >> > + * some larger memory area. >> > + */ >> > + if (r->start <= range->start && r->end >= range->end) { >> > + if (r->start == range->start) { >> > + /* Shrink the start of this memory range */ >> > + r->start = range->end + 1; >> > + } else if (r->end == range->end) { >> > + /* Shrink the end of this memory range */ >> > + r->end = range->start - 1; >> >> What if r->start == range->start) && (r->end == range->end)? > > I suppose that could happen, so what about this patch on top (untested). I think, it should be fine, except..... > This isn't something I'd be able to test on real hardware, it needs a > separate test-suite to be written to do modular testing... > > kexec/mem_regions.c | 94 +++++++++++++++++++++++++++++++---------------------- > 1 file changed, 55 insertions(+), 39 deletions(-) > > diff --git a/kexec/mem_regions.c b/kexec/mem_regions.c > index c6ba942..4e7061b 100644 > --- a/kexec/mem_regions.c > +++ b/kexec/mem_regions.c > @@ -29,6 +29,50 @@ void mem_regions_sort(struct memory_ranges *ranges) > } > > /** > + * mem_regions_add() - add a memory region to a set of ranges > + * @ranges: ranges to add the memory region to > + * @max: maximum number of entries in memory region > + * @base: base address of memory region > + * @length: length of memory region in bytes > + * @type: type of memory region > + * > + * Add the memory region to the set of ranges, and return %0 if successful, > + * or %-1 if we ran out of space. > + */ > +int mem_regions_add(struct memory_ranges *ranges, unsigned long long base, > + unsigned long long length, int type) > +{ > + struct memory_range *range; > + > + if (ranges->size >= ranges->max_size) > + return -1; > + > + range = ranges->ranges + ranges->size++; > + range->start = base; > + range->end = base + length - 1; > + range->type = type; > + > + return 0; > +} > + > +static void mem_regions_remove(struct memory_ranges *ranges, int index) > +{ > + int tail_entries; > + > + /* we are assured to have at least one entry */ > + ranges->size -= 1; > + > + /* if we have following entries, shuffle them down one place */ > + tail_entries = ranges->size - index; > + if (tail_entries) > + memmove(ranges->ranges + index, ranges->ranges + index + 1, > + tail_entries * sizeof(*ranges->ranges)); > + > + /* zero the new tail entry */ > + memset(ranges->ranges + ranges->size, 0, sizeof(*ranges->ranges)); > +} > + > +/** > * mem_regions_exclude() - excludes a memory region from a set of memory ranges > * @ranges: memory ranges to exclude the region from > * @range: memory range to exclude > @@ -40,7 +84,7 @@ void mem_regions_sort(struct memory_ranges *ranges) > int mem_regions_exclude(struct memory_ranges *ranges, > const struct memory_range *range) > { > - int i; > + int i, ret; > > for (i = 0; i < ranges->size; i++) { > struct memory_range *r = ranges->ranges + i; > @@ -51,25 +95,25 @@ int mem_regions_exclude(struct memory_ranges *ranges, > */ > if (r->start <= range->start && r->end >= range->end) { > if (r->start == range->start) { > - /* Shrink the start of this memory range */ > - r->start = range->end + 1; > + if (r->end == range->end) > + /* Remove this entry */ > + mem_regions_remove(ranges, i); > + else > + /* Shrink the start of this memory range */ > + r->start = range->end + 1; > } else if (r->end == range->end) { > /* Shrink the end of this memory range */ > r->end = range->start - 1; > } else { > - struct memory_range *new; > - > /* > * Split this area into 2 smaller ones and > * remove excluded range from between. First > * create new entry for the remaining area. > */ > - if (ranges->size >= ranges->max_size) > - return -1; > - > - new = ranges->ranges + ranges->size++; > - new->start = range->end + 1; > - new->end = r->end; > + ret = mem_regions_add(ranges, range->end + 1, > + r->end, 0); 3rd argument should be (r->end - range->end) > + if (ret < 0) > + return ret; > > /* > * Update this area to end before excluded > @@ -82,31 +126,3 @@ int mem_regions_exclude(struct memory_ranges *ranges, > } > return 0; > } > - > -/** > - * mem_regions_add() - add a memory region to a set of ranges > - * @ranges: ranges to add the memory region to > - * @max: maximum number of entries in memory region > - * @base: base address of memory region > - * @length: length of memory region in bytes > - * @type: type of memory region > - * > - * Add the memory region to the set of ranges, and return %0 if successful, > - * or %-1 if we ran out of space. > - */ > -int mem_regions_add(struct memory_ranges *ranges, unsigned long long base, > - unsigned long long length, int type) > -{ > - struct memory_range *range; > - > - if (ranges->size >= ranges->max_size) > - return -1; > - > - range = ranges->ranges + ranges->size++; > - range->start = base; > - range->end = base + length - 1; > - range->type = type; > - > - return 0; > -} > - > > > -- > RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ > FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up > according to speedtest.net. ~Pratyush
On Fri, May 27, 2016 at 08:37:41PM +0530, Pratyush Anand wrote: > On Thu, May 26, 2016 at 2:26 PM, Russell King - ARM Linux > <linux@armlinux.org.uk> wrote: > > - new = ranges->ranges + ranges->size++; > > - new->start = range->end + 1; > > - new->end = r->end; > > + ret = mem_regions_add(ranges, range->end + 1, > > + r->end, 0); > > 3rd argument should be (r->end - range->end) Yes indeed, thanks for pointing that out.
diff --git a/kexec/mem_regions.c b/kexec/mem_regions.c index c6ba942..4e7061b 100644 --- a/kexec/mem_regions.c +++ b/kexec/mem_regions.c @@ -29,6 +29,50 @@ void mem_regions_sort(struct memory_ranges *ranges) } /** + * mem_regions_add() - add a memory region to a set of ranges + * @ranges: ranges to add the memory region to + * @max: maximum number of entries in memory region + * @base: base address of memory region + * @length: length of memory region in bytes + * @type: type of memory region + * + * Add the memory region to the set of ranges, and return %0 if successful, + * or %-1 if we ran out of space. + */ +int mem_regions_add(struct memory_ranges *ranges, unsigned long long base, + unsigned long long length, int type) +{ + struct memory_range *range; + + if (ranges->size >= ranges->max_size) + return -1; + + range = ranges->ranges + ranges->size++; + range->start = base; + range->end = base + length - 1; + range->type = type; + + return 0; +} + +static void mem_regions_remove(struct memory_ranges *ranges, int index) +{ + int tail_entries; + + /* we are assured to have at least one entry */ + ranges->size -= 1; + + /* if we have following entries, shuffle them down one place */ + tail_entries = ranges->size - index; + if (tail_entries) + memmove(ranges->ranges + index, ranges->ranges + index + 1, + tail_entries * sizeof(*ranges->ranges)); + + /* zero the new tail entry */ + memset(ranges->ranges + ranges->size, 0, sizeof(*ranges->ranges)); +} + +/** * mem_regions_exclude() - excludes a memory region from a set of memory ranges * @ranges: memory ranges to exclude the region from * @range: memory range to exclude @@ -40,7 +84,7 @@ void mem_regions_sort(struct memory_ranges *ranges) int mem_regions_exclude(struct memory_ranges *ranges, const struct memory_range *range) { - int i; + int i, ret; for (i = 0; i < ranges->size; i++) { struct memory_range *r = ranges->ranges + i; @@ -51,25 +95,25 @@ int mem_regions_exclude(struct memory_ranges *ranges, */ if (r->start <= range->start && r->end >= range->end) { if (r->start == range->start) { - /* Shrink the start of this memory range */ - r->start = range->end + 1; + if (r->end == range->end) + /* Remove this entry */ + mem_regions_remove(ranges, i); + else + /* Shrink the start of this memory range */ + r->start = range->end + 1; } else if (r->end == range->end) { /* Shrink the end of this memory range */ r->end = range->start - 1; } else { - struct memory_range *new; - /* * Split this area into 2 smaller ones and * remove excluded range from between. First * create new entry for the remaining area. */ - if (ranges->size >= ranges->max_size) - return -1; - - new = ranges->ranges + ranges->size++; - new->start = range->end + 1; - new->end = r->end; + ret = mem_regions_add(ranges, range->end + 1, + r->end, 0); + if (ret < 0) + return ret; /* * Update this area to end before excluded @@ -82,31 +126,3 @@ int mem_regions_exclude(struct memory_ranges *ranges, } return 0; } - -/** - * mem_regions_add() - add a memory region to a set of ranges - * @ranges: ranges to add the memory region to - * @max: maximum number of entries in memory region - * @base: base address of memory region - * @length: length of memory region in bytes - * @type: type of memory region - * - * Add the memory region to the set of ranges, and return %0 if successful, - * or %-1 if we ran out of space. - */ -int mem_regions_add(struct memory_ranges *ranges, unsigned long long base, - unsigned long long length, int type) -{ - struct memory_range *range; - - if (ranges->size >= ranges->max_size) - return -1; - - range = ranges->ranges + ranges->size++; - range->start = base; - range->end = base + length - 1; - range->type = type; - - return 0; -} -