From 378c18e5f024ac5a8aef4cb40d7c9aa9633d144c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:30:35 +0200 Subject: Adding upstream version 2.38.1. Signed-off-by: Daniel Baumann --- libblkid/src/topology/md.c | 154 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 libblkid/src/topology/md.c (limited to 'libblkid/src/topology/md.c') diff --git a/libblkid/src/topology/md.c b/libblkid/src/topology/md.c new file mode 100644 index 0000000..02f27a8 --- /dev/null +++ b/libblkid/src/topology/md.c @@ -0,0 +1,154 @@ +/* + * Linux Software RAID (md) topology + * -- this is fallback for old systems where the topology information is not + * exported by sysfs + * + * Copyright (C) 2009 Karel Zak + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "topology.h" + +#ifndef MD_MAJOR +#define MD_MAJOR 9 +#endif + +#ifndef _IOT__IOTBASE_uint32_t +#define _IOT__IOTBASE_uint32_t IOT_SIMPLE(uint32_t) +#endif +#define _IOT_md_array_info _IOT (_IOTS(uint32_t), 18, 0, 0, 0, 0) +#define GET_ARRAY_INFO _IOR (MD_MAJOR, 0x11, struct md_array_info) + +struct md_array_info { + /* + * Generic constant information + */ + uint32_t major_version; + uint32_t minor_version; + uint32_t patch_version; + uint32_t ctime; + uint32_t level; + uint32_t size; + uint32_t nr_disks; + uint32_t raid_disks; + uint32_t md_minor; + uint32_t not_persistent; + + /* + * Generic state information + */ + uint32_t utime; /* 0 Superblock update time */ + uint32_t state; /* 1 State bits (clean, ...) */ + uint32_t active_disks; /* 2 Number of currently active disks */ + uint32_t working_disks; /* 3 Number of working disks */ + uint32_t failed_disks; /* 4 Number of failed disks */ + uint32_t spare_disks; /* 5 Number of spare disks */ + + /* + * Personality information + */ + uint32_t layout; /* 0 the array's physical layout */ + uint32_t chunk_size; /* 1 chunk size in bytes */ + +}; + +static int is_md_device(dev_t devno) +{ + if (major(devno) == MD_MAJOR) + return 1; + return blkid_driver_has_major("md", major(devno)); +} + +static int probe_md_tp(blkid_probe pr, + const struct blkid_idmag *mag __attribute__((__unused__))) +{ + int fd = -1; + dev_t disk = 0; + dev_t devno = blkid_probe_get_devno(pr); + struct md_array_info md; + + if (!devno) + goto nothing; /* probably not a block device */ + + if (!is_md_device(devno)) + goto nothing; + + if (blkid_devno_to_wholedisk(devno, NULL, 0, &disk)) + goto nothing; + + if (disk == devno) + fd = pr->fd; + else { + char *diskpath = blkid_devno_to_devname(disk); + + if (!diskpath) + goto nothing; + + fd = open(diskpath, O_RDONLY|O_CLOEXEC); + free(diskpath); + + if (fd == -1) + goto nothing; + } + + memset(&md, 0, sizeof(md)); + + if (ioctl(fd, GET_ARRAY_INFO, &md)) + goto nothing; + + if (fd >= 0 && fd != pr->fd) { + close(fd); + fd = -1; + } + + /* + * Ignore levels we don't want aligned (e.g. linear) + * and deduct disk(s) from stripe width on RAID4/5/6 + */ + switch (md.level) { + case 6: + md.raid_disks--; + /* fallthrough */ + case 5: + case 4: + md.raid_disks--; + /* fallthrough */ + case 1: + case 0: + case 10: + break; + default: + goto nothing; + } + + blkid_topology_set_minimum_io_size(pr, md.chunk_size); + blkid_topology_set_optimal_io_size(pr, (unsigned long) md.chunk_size * md.raid_disks); + + return 0; + +nothing: + if (fd >= 0 && fd != pr->fd) + close(fd); + return 1; +} + +const struct blkid_idinfo md_tp_idinfo = +{ + .name = "md", + .probefunc = probe_md_tp, + .magics = BLKID_NONE_MAGIC +}; + -- cgit v1.2.3