bcache-tools:Do a entire discard when 'bcache make' for cache devices.
If discard successfully, it will be prompted, or do nothing.
Thanks for appreciation.
Coly Li <colyli@xxxxxxx> 于2019年6月6日周四 下午7:42写道：
>
> On 2019/6/6 10:06 上午, Xinwei Wei wrote:
> > Signed-off-by: Xinwei Wei <xinweiwei90@xxxxxxxxx>
> > ---
>
> The code looks good to me. Could you please to offer a detailed commit log ?
>
> Thanks.
>
> Coly Li
>
> > make.c | 48 +++++++++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 47 insertions(+), 1 deletion(-)
> >
> > diff --git a/make.c b/make.c
> > index e5e7464..4244866 100644
> > --- a/make.c
> > +++ b/make.c
> > @@ -179,6 +179,48 @@ const char * const cache_replacement_policies[] = {
> > NULL
> > };
> >
> > +int blkdiscard_all(char *path, int fd)
> > +{
> > + printf("%s blkdiscard beginning...", path);
> > + fflush(stdout);
> > +
> > + uint64_t end, blksize, secsize, range[2];
> > + struct stat sb;
> > +
> > + range[0] = 0;
> > + range[1] = ULLONG_MAX;
> > +
> > + if (fstat(fd, &sb) == -1)
> > + goto err;
> > +
> > + if (!S_ISBLK(sb.st_mode))
> > + goto err;
> > +
> > + if (ioctl(fd, BLKGETSIZE64, &blksize))
> > + goto err;
> > +
> > + if (ioctl(fd, BLKSSZGET, &secsize))
> > + goto err;
> > +
> > + /* align range to the sector size */
> > + range[0] = (range[0] + secsize - 1) & ~(secsize - 1);
> > + range[1] &= ~(secsize - 1);
> > +
> > + /* is the range end behind the end of the device ?*/
> > + end = range[0] + range[1];
> > + if (end < range[0] || end > blksize)
> > + range[1] = blksize - range[0];
> > +
> > + if (ioctl(fd, BLKDISCARD, &range))
> > + goto err;
> > +
> > + printf("done\n");
> > + return 0;
> > +err:
> > + printf("\r ");
> > + return -1;
> > +}
> > +
> > static void write_sb(char *dev, unsigned int block_size,
> > unsigned int bucket_size,
> > bool writeback, bool discard, bool wipe_bcache,
> > @@ -354,6 +396,10 @@ static void write_sb(char *dev, unsigned int block_size,
> > sb.nr_in_set,
> > sb.nr_this_dev,
> > sb.first_bucket);
> > +
> > + /* Attempting to discard cache device
> > + */
> > + blkdiscard_all(dev, fd);
> > putchar('\n');
> > }
> >
> > @@ -429,7 +475,7 @@ int make_bcache(int argc, char **argv)
> > unsigned int i, ncache_devices = 0, nbacking_devices = 0;
> > char *cache_devices[argc];
> > char *backing_devices[argc];
> > - char label[SB_LABEL_SIZE];
> > + char label[SB_LABEL_SIZE] = { 0 };
> > unsigned int block_size = 0, bucket_size = 1024;
> > int writeback = 0, discard = 0, wipe_bcache = 0, force = 0;
> > unsigned int cache_replacement_policy = 0;
> >
