On Fri, Dec 02, 2011 at 11:34:54AM -0500, Phillip Susi wrote: > On 12/2/2011 3:50 AM, Petr Uzel wrote: > >Hm, this code was hardly readable before and now with the ifdefs and > >ifndefs, it is even harder not to get lost in it. Perhaps this could > >be factored out somehow to separate function? Eventually also using > >/sys/block/DEV/PART/start as a fallback if the new ioctl() is not > >available? > > > >http://lists.alioth.debian.org/pipermail/parted-devel/2011-November/003975.html > > I merged your patch with mine.
> How does this look? You did not try to compile it, did you? :) See comments below. > > > From d45ed0d6cb2519464807f4185a5ad1644e802507 Mon Sep 17 00:00:00 2001 > From: Phillip Susi <[email protected]> > Date: Wed, 30 Nov 2011 21:24:45 -0500 > Subject: [PATCH] Avoid the HDIO_GETGEO when possible > > We were using the long depreciated HDIO_GETGEO ioctl on the > partition to get its start sector. Use the new BLKPG_GET_PARTITION > ioctl instead. This allows for disks > 2TB and partitioned loop > devices, which don't support HDIO_GETGEO. As a fallback when > BLKPG_GET_PARTITION fails or is not availible, try getting the > values from sysfs, and finally use BLKGETSIZE64 and HDIO_GETGEO > as a last resort. > > This modifies and superceeds Petr Uzel's patch: > libparted: fix reading partition start sector from kernel > --- > libparted/arch/linux.c | 124 ++++++++++++++++++++++++++++++++++++++++------- > 1 files changed, 105 insertions(+), 19 deletions(-) > > diff --git a/libparted/arch/linux.c b/libparted/arch/linux.c > index 3799b9d..2d10b80 100644 > --- a/libparted/arch/linux.c > +++ b/libparted/arch/linux.c > @@ -2410,6 +2410,25 @@ _blkpg_remove_partition (PedDisk* disk, int n) > BLKPG_DEL_PARTITION); > } > > +#ifdef BLKPG_GET_PARTITION > +static int > +_blkpg_get_partition (PedPartition *part, long long *start, long long > *length) > +{ > + struct blkpg_partition linux_part; > + int ret; > + > + memset (&linux_part, 0, sizeof (linux_part)); > + linux_part.pno = part->num; > + if (_blkpg_part_command (part->disk->dev, &linux_part, > + BLKPG_GET_PARTITION)) > + { > + *start = linux_part.start; > + *length = linux_part.length; > + return 1; > + } else return 0; > +} > +#endif > + > /* Read the integer from /sys/block/DEV_BASE/ENTRY and set *VAL > to that value, where DEV_BASE is the last component of DEV->path. > Upon success, return true. Otherwise, return false. */ > @@ -2432,6 +2451,85 @@ _sysfs_int_entry_from_dev(PedDevice const* dev, const > char *entry, int *val) > return ok; > } > > +/* Read the unsigned long long from /sys/block/DEV_BASE/PART_BASE/ENTRY > + and set *VAL to that value, where DEV_BASE is the last component of path > to > + block device corresponding to PART and PART_BASE is the sysfs name of > PART. > + Upon success, return true. Otherwise, return false. */ > +static bool > +_sysfs_ull_entry_from_part(PedPartition const* part, const char *entry, > unsigned long long *val) > +{ > + char path[128]; > + char *part_name = linux_partition_get_path(part); > + if (!part_name) > + return false; > + > + int r = snprintf(path, sizeof(path), "/sys/block/%s/%s/%s", > + last_component(part->disk->dev->path), > + last_component(part_name), entry); > + free(part_name); > + if (r < 0 || r >= sizeof(path)) > + return false; > + > + FILE *fp = fopen(path, "r"); > + if (!fp) > + return false; > + > + bool ok = fscanf(fp, "%llu", val) == 1; > + fclose(fp); > + > + return ok; > +} > + > + > +/* Get the starting sector and length of a partition PART within a block > device > + * Use blkpg if availible, then check sysfs and then use HDIO_GETGEO and > BLKGETSIZE64 > + * ioctls as fallback. Upon success, return true. Otherwise, return false. */ > +static bool > +_kernel_get_partition_start_and_legnth(PedPartition const *part, unsigned > long long *start, > + unsigned long long *length) Typo: s/legnth/length > +{ > + int fd = -1; > + int ok; > + PED_ASSERT(part); > + PED_ASSERT(start); > + PED_ASSERT(length); > + Trailing whitespace ^^ > +#ifdef BLKPG_GET_PARTITION > + ok = _blkpg_get_partition (part, start, length); > + if (ok) > + return ok; > +#endif > + char *dev_name = linux_partition_get_path (part); > + if (!dev_name) > + return false; > + > + ok = _sysfs_ull_entry_from_part (part, "start", start); > + if (!ok) { > + struct hd_geometry geom; > + int fd = open (dev_name, O_RDONLY); > + if (fd != -1 && ioctl (fd, HDIO_GETGEO, &geom)) { > + *val = geom.start; val is undeclared. s/val/start ? > + ok = true; Missing '}' ^^ here > + } > + ok = _sysfs_ull_entry_from_part (part, "size", length); > + if (!ok) > + { > + if (fd == -1) > + fd = open (dev_name, O_RDONLY); > + if (fd != -1 && ioctl (fd, BLKGETSIZE64, length)) > + ok = true; > + } > + if (ok) > + *length /= part->disk->dev->sector_size; > + if (fd != -1) > + close (fd); > + > + free (dev_name); > + return ok; > +} > + > + > + > /* > * The number of partitions that a device can have depends on the kernel. > * If we don't find this value in /sys/block/DEV/ext_range, we will use our > own > @@ -2519,30 +2617,18 @@ _disk_sync_part_table (PedDisk* disk) > const PedPartition *part = ped_disk_get_partition (disk, i); > if (part) { > if (!ok[i - 1] && errnums[i - 1] == EBUSY) { > - struct hd_geometry geom; > - unsigned long long length = 0; > + unsigned long long length; > + unsigned long long start; > /* get start and length of existing > partition */ > - char *dev_name = _device_get_part_path > (disk->dev, i); > - if (!dev_name) > - goto cleanup; > - int fd = open (dev_name, O_RDONLY); > - if (fd == -1 > - || ioctl (fd, HDIO_GETGEO, &geom) > - || ioctl (fd, BLKGETSIZE64, &length)) { > + if > (!_kernel_get_partition_start_and_length(part, &start, &length)) { _kernel_get_partition_start_and_length udeclared -> see the typo above > ped_exception_throw ( > - > PED_EXCEPTION_BUG, > - > PED_EXCEPTION_CANCEL, > + PED_EXCEPTION_BUG, > + PED_EXCEPTION_CANCEL, > _("Unable to determine the size and length of %s."), > - dev_name); dev_name undeclared > - if (fd != -1) > - close (fd); > - free (dev_name); > + dev_name); > goto cleanup; > } > - free (dev_name); > - length /= disk->dev->sector_size; > - close (fd); > - if (geom.start == part->geom.start > + if (start == part->geom.start > && length == part->geom.length) > ok[i - 1] = 1; > /* If the new partition is unchanged and the > -- > 1.7.5.4 > Petr -- Petr Uzel IRC: ptr_uzl @ freenode
