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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/hw/block/hd-geometry.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/hw/block/hd-geometry.c')
-rw-r--r--qemu/hw/block/hd-geometry.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/qemu/hw/block/hd-geometry.c b/qemu/hw/block/hd-geometry.c
new file mode 100644
index 000000000..b187878fa
--- /dev/null
+++ b/qemu/hw/block/hd-geometry.c
@@ -0,0 +1,165 @@
+/*
+ * Hard disk geometry utilities
+ *
+ * Copyright (C) 2012 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ * Copyright (c) 2003 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "sysemu/block-backend.h"
+#include "hw/block/block.h"
+#include "trace.h"
+
+struct partition {
+ uint8_t boot_ind; /* 0x80 - active */
+ uint8_t head; /* starting head */
+ uint8_t sector; /* starting sector */
+ uint8_t cyl; /* starting cylinder */
+ uint8_t sys_ind; /* What partition type */
+ uint8_t end_head; /* end head */
+ uint8_t end_sector; /* end sector */
+ uint8_t end_cyl; /* end cylinder */
+ uint32_t start_sect; /* starting sector counting from 0 */
+ uint32_t nr_sects; /* nr of sectors in partition */
+} QEMU_PACKED;
+
+/* try to guess the disk logical geometry from the MSDOS partition table.
+ Return 0 if OK, -1 if could not guess */
+static int guess_disk_lchs(BlockBackend *blk,
+ int *pcylinders, int *pheads, int *psectors)
+{
+ uint8_t buf[BDRV_SECTOR_SIZE];
+ int i, heads, sectors, cylinders;
+ struct partition *p;
+ uint32_t nr_sects;
+ uint64_t nb_sectors;
+
+ blk_get_geometry(blk, &nb_sectors);
+
+ /**
+ * The function will be invoked during startup not only in sync I/O mode,
+ * but also in async I/O mode. So the I/O throttling function has to
+ * be disabled temporarily here, not permanently.
+ */
+ if (blk_read_unthrottled(blk, 0, buf, 1) < 0) {
+ return -1;
+ }
+ /* test msdos magic */
+ if (buf[510] != 0x55 || buf[511] != 0xaa) {
+ return -1;
+ }
+ for (i = 0; i < 4; i++) {
+ p = ((struct partition *)(buf + 0x1be)) + i;
+ nr_sects = le32_to_cpu(p->nr_sects);
+ if (nr_sects && p->end_head) {
+ /* We make the assumption that the partition terminates on
+ a cylinder boundary */
+ heads = p->end_head + 1;
+ sectors = p->end_sector & 63;
+ if (sectors == 0) {
+ continue;
+ }
+ cylinders = nb_sectors / (heads * sectors);
+ if (cylinders < 1 || cylinders > 16383) {
+ continue;
+ }
+ *pheads = heads;
+ *psectors = sectors;
+ *pcylinders = cylinders;
+ trace_hd_geometry_lchs_guess(blk, cylinders, heads, sectors);
+ return 0;
+ }
+ }
+ return -1;
+}
+
+static void guess_chs_for_size(BlockBackend *blk,
+ uint32_t *pcyls, uint32_t *pheads, uint32_t *psecs)
+{
+ uint64_t nb_sectors;
+ int cylinders;
+
+ blk_get_geometry(blk, &nb_sectors);
+
+ cylinders = nb_sectors / (16 * 63);
+ if (cylinders > 16383) {
+ cylinders = 16383;
+ } else if (cylinders < 2) {
+ cylinders = 2;
+ }
+ *pcyls = cylinders;
+ *pheads = 16;
+ *psecs = 63;
+}
+
+void hd_geometry_guess(BlockBackend *blk,
+ uint32_t *pcyls, uint32_t *pheads, uint32_t *psecs,
+ int *ptrans)
+{
+ int cylinders, heads, secs, translation;
+ HDGeometry geo;
+
+ /* Try to probe the backing device geometry, otherwise fallback
+ to the old logic. (as of 12/2014 probing only succeeds on DASDs) */
+ if (blk_probe_geometry(blk, &geo) == 0) {
+ *pcyls = geo.cylinders;
+ *psecs = geo.sectors;
+ *pheads = geo.heads;
+ translation = BIOS_ATA_TRANSLATION_NONE;
+ } else if (guess_disk_lchs(blk, &cylinders, &heads, &secs) < 0) {
+ /* no LCHS guess: use a standard physical disk geometry */
+ guess_chs_for_size(blk, pcyls, pheads, psecs);
+ translation = hd_bios_chs_auto_trans(*pcyls, *pheads, *psecs);
+ } else if (heads > 16) {
+ /* LCHS guess with heads > 16 means that a BIOS LBA
+ translation was active, so a standard physical disk
+ geometry is OK */
+ guess_chs_for_size(blk, pcyls, pheads, psecs);
+ translation = *pcyls * *pheads <= 131072
+ ? BIOS_ATA_TRANSLATION_LARGE
+ : BIOS_ATA_TRANSLATION_LBA;
+ } else {
+ /* LCHS guess with heads <= 16: use as physical geometry */
+ *pcyls = cylinders;
+ *pheads = heads;
+ *psecs = secs;
+ /* disable any translation to be in sync with
+ the logical geometry */
+ translation = BIOS_ATA_TRANSLATION_NONE;
+ }
+ if (ptrans) {
+ *ptrans = translation;
+ }
+ trace_hd_geometry_guess(blk, *pcyls, *pheads, *psecs, translation);
+}
+
+int hd_bios_chs_auto_trans(uint32_t cyls, uint32_t heads, uint32_t secs)
+{
+ return cyls <= 1024 && heads <= 16 && secs <= 63
+ ? BIOS_ATA_TRANSLATION_NONE
+ : BIOS_ATA_TRANSLATION_LBA;
+}