The fs_shell now also works with devices that don't return a correct

hd_geometry, but do support the BLKGETSIZE64 ioctl (it just crashed 
before).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@23064 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/tools/fs_shell/unistd.cpp

@@ -29,6 +29,7 @@
 
 #	if defined(HAIKU_HOST_PLATFORM_LINUX)
 #		include <linux/hdreg.h>
+#		include <linux/fs.h>
 #	endif
 #endif
 
@@ -155,6 +156,23 @@ fssh_ioctl(int fd, unsigned long op, ...)
 				// to be HDIO_GETGEO, which is kind of obsolete, BTW), and
 				// get the partition size via binary search.
 				if (ioctl(fd, HDIO_GETGEO, &hdGeometry) == 0) {
+					int blockSize = 512;
+					if (hdGeometry.heads == 0) {
+						off_t size;
+						if (ioctl(fd, BLKGETSIZE64, &size) == 0) {
+							off_t blocks = size / blockSize;
+							uint32_t heads = (blocks + ULONG_MAX - 1)
+								/ ULONG_MAX;
+							if (heads == 0)
+								heads = 1;
+
+							geometry->head_count = heads;
+							geometry->cylinder_count = blocks / heads;
+							geometry->sectors_per_track = 1;
+							error = B_OK;
+						} else
+							error = errno;
+					} else {
 						off_t bytesPerCylinder = (off_t)hdGeometry.heads
 							* hdGeometry.sectors * 512;
 						off_t deviceSize = bytesPerCylinder * hdGeometry.cylinders;
@@ -163,14 +181,17 @@ fssh_ioctl(int fd, unsigned long op, ...)
 						geometry->head_count = hdGeometry.heads;
 						geometry->cylinder_count = partitionSize / bytesPerCylinder;
 						geometry->sectors_per_track = hdGeometry.sectors;
+						error = B_OK;
+					}
 
+					if (error == B_OK) {
 						// TODO: Get the real values...
-					geometry->bytes_per_sector = 512;
+						geometry->bytes_per_sector = blockSize;
 						geometry->device_type = FSSH_B_DISK;
 						geometry->removable = false;
 						geometry->read_only = false;
 						geometry->write_once = false;
-					error = B_OK;
+					}
 				} else
 					error = errno;