external/gpl2/lvm2/dist/lib/device/device.h

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
   5  * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
   6  *
   7  * This file is part of LVM2.
   8  *
   9  * This copyrighted material is made available to anyone wishing to use,
  10  * modify, copy, or redistribute it subject to the terms and conditions
  11  * of the GNU Lesser General Public License v.2.1.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this program; if not, write to the Free Software Foundation,
  15  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16  */
  17
  18 #ifndef _LVM_DEVICE_H
  19 #define _LVM_DEVICE_H
  20
  21 #include "uuid.h"
  22
  23 #include <fcntl.h>
  24
  25 #define DEV_ACCESSED_W          0x00000001      /* Device written to? */
  26 #define DEV_REGULAR             0x00000002      /* Regular file? */
  27 #define DEV_ALLOCED             0x00000004      /* dm_malloc used */
  28 #define DEV_OPENED_RW           0x00000008      /* Opened RW */
  29 #define DEV_OPENED_EXCL         0x00000010      /* Opened EXCL */
  30 #define DEV_O_DIRECT            0x00000020      /* Use O_DIRECT */
  31 #define DEV_O_DIRECT_TESTED     0x00000040      /* DEV_O_DIRECT is reliable */
  32
  33 /*
  34  * All devices in LVM will be represented by one of these.
  35  * pointer comparisons are valid.
  36  */
  37 struct device {
  38         struct dm_list aliases; /* struct str_list from lvm-types.h */
  39         dev_t dev;
  40
  41         /* private */
  42         int fd;
  43         int open_count;
  44         int block_size;
  45         int read_ahead;
  46         uint32_t flags;
  47         uint64_t end;
  48         struct dm_list open_list;
  49
  50         char pvid[ID_LEN + 1];
  51         char _padding[7];
  52 };
  53
  54 struct device_list {
  55         struct dm_list list;
  56         struct device *dev;
  57 };
  58
  59 struct device_area {
  60         struct device *dev;
  61         uint64_t start;         /* Bytes */
  62         uint64_t size;          /* Bytes */
  63 };
  64
  65 /*
  66  * All io should use these routines.
  67  */
  68 int dev_get_size(const struct device *dev, uint64_t *size);
  69 int dev_get_sectsize(struct device *dev, uint32_t *size);
  70 int dev_get_read_ahead(struct device *dev, uint32_t *read_ahead);
  71
  72 /* Use quiet version if device number could change e.g. when opening LV */
  73 int dev_open(struct device *dev);
  74 int dev_open_quiet(struct device *dev);
  75 int dev_open_flags(struct device *dev, int flags, int direct, int quiet);
  76 int dev_close(struct device *dev);
  77 int dev_close_immediate(struct device *dev);
  78 void dev_close_all(void);
  79 int dev_test_excl(struct device *dev);
  80
  81 int dev_fd(struct device *dev);
  82 const char *dev_name(const struct device *dev);
  83
  84 int dev_read(struct device *dev, uint64_t offset, size_t len, void *buffer);
  85 int dev_read_circular(struct device *dev, uint64_t offset, size_t len,
  86                       uint64_t offset2, size_t len2, void *buf);
  87 int dev_write(struct device *dev, uint64_t offset, size_t len, void *buffer);
  88 int dev_append(struct device *dev, size_t len, void *buffer);
  89 int dev_set(struct device *dev, uint64_t offset, size_t len, int value);
  90 void dev_flush(struct device *dev);
  91
  92 struct device *dev_create_file(const char *filename, struct device *dev,
  93                                struct str_list *alias, int use_malloc);
  94
  95 /* Return a valid device name from the alias list; NULL otherwise */
  96 const char *dev_name_confirmed(struct device *dev, int quiet);
  97
  98 /* Does device contain md superblock?  If so, where? */
  99 int dev_is_md(struct device *dev, uint64_t *sb);
 100 int dev_is_swap(struct device *dev, uint64_t *signature);
 101 unsigned long dev_md_stripe_width(const char *sysfs_dir, struct device *dev);
 102
 103 int is_partitioned_dev(struct device *dev);
 104
 105 int get_primary_dev(const char *sysfs_dir,
 106                     struct device *dev, dev_t *result);
 107
 108 unsigned long dev_alignment_offset(const char *sysfs_dir,
 109                                    struct device *dev);
 110
 111 unsigned long dev_minimum_io_size(const char *sysfs_dir,
 112                                   struct device *dev);
 113
 114 unsigned long dev_optimal_io_size(const char *sysfs_dir,
 115                                   struct device *dev);
 116
 117 #endif