/* * include/linux/lvm.h * kernel/lvm.h * tools/lib/lvm.h * * Copyright (C) 1997 - 2002 Heinz Mauelshagen, Sistina Software * * February-November 1997 * May-July 1998 * January-March,July,September,October,Dezember 1999 * January,February,July,November 2000 * January-March,June,July 2001 * May 2002 * * lvm is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * lvm is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GNU CC; see the file COPYING. If not, write to * the Free Software Foundation, 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * */ /* * Changelog * * 10/10/1997 - beginning of new structure creation * 12/05/1998 - incorporated structures from lvm_v1.h and deleted lvm_v1.h * 07/06/1998 - avoided LVM_KMALLOC_MAX define by using vmalloc/vfree * instead of kmalloc/kfree * 01/07/1998 - fixed wrong LVM_MAX_SIZE * 07/07/1998 - extended pe_t structure by ios member (for statistic) * 02/08/1998 - changes for official char/block major numbers * 07/08/1998 - avoided init_module() and cleanup_module() to be static * 29/08/1998 - seprated core and disk structure type definitions * 01/09/1998 - merged kernel integration version (mike) * 20/01/1999 - added LVM_PE_DISK_OFFSET macro for use in * vg_read_with_pv_and_lv(), pv_move_pe(), pv_show_pe_text()... * 18/02/1999 - added definition of time_disk_t structure for; * keeps time stamps on disk for nonatomic writes (future) * 15/03/1999 - corrected LV() and VG() macro definition to use argument * instead of minor * 03/07/1999 - define for genhd.c name handling * 23/07/1999 - implemented snapshot part * 08/12/1999 - changed LVM_LV_SIZE_MAX macro to reflect current 1TB limit * 01/01/2000 - extended lv_v2 core structure by wait_queue member * 12/02/2000 - integrated Andrea Arcagnelli's snapshot work * 18/02/2000 - seperated user and kernel space parts by * #ifdef them with __KERNEL__ * 08/03/2000 - implemented cluster/shared bits for vg_access * 26/06/2000 - implemented snapshot persistency and resizing support * 02/11/2000 - added hash table size member to lv structure * 12/11/2000 - removed unneeded timestamp definitions * 24/12/2000 - removed LVM_TO_{CORE,DISK}*, use cpu_{from, to}_le* * instead - Christoph Hellwig * 22/01/2001 - Change ulong to uint32_t * 14/02/2001 - changed LVM_SNAPSHOT_MIN_CHUNK to 1 page * 20/02/2001 - incremented IOP version to 11 because of incompatible * change in VG activation (in order to support devfs better) * 01/03/2001 - Revert to IOP10 and add VG_CREATE_OLD call for compatibility * 08/03/2001 - new lv_t (in core) version number 5: changed page member * to (struct kiobuf *) to use for COW exception table io * 26/03/2001 - changed lv_v4 to lv_v5 in structure definition (HM) * 21/06/2001 - changed BLOCK_SIZE back to 1024 for non S/390 * 22/06/2001 - added Andreas Dilger's PE on 4k boundary alignment enhancements * 19/07/2001 - added rwsem compatibility macros for 2.2 kernels * 13/11/2001 - reduced userspace inclusion of kernel headers to a minimum * */ #ifndef _LVM_H_INCLUDE #define _LVM_H_INCLUDE #define LVM_RELEASE_NAME "1.0.8" #define LVM_RELEASE_DATE "17/11/2003" #define _LVM_KERNEL_H_VERSION "LVM "LVM_RELEASE_NAME" ("LVM_RELEASE_DATE")" #include /* * preprocessor definitions */ /* if you like emergency reset code in the driver */ #define LVM_TOTAL_RESET #ifdef __KERNEL__ #undef LVM_HD_NAME /* display nice names in /proc/partitions */ /* lots of debugging output (see driver source) #define DEBUG_LVM_GET_INFO #define DEBUG #define DEBUG_MAP #define DEBUG_MAP_SIZE #define DEBUG_IOCTL #define DEBUG_READ #define DEBUG_GENDISK #define DEBUG_VG_CREATE #define DEBUG_DEVICE #define DEBUG_KFREE */ #include #include #include #include #else /* This prevents the need to include which causes problems on some platforms. It's not nice but then neither is the alternative. */ struct list_head { struct list_head *next, *prev; }; #define __KERNEL__ #include #undef __KERNEL__ #endif /* #ifndef __KERNEL__ */ #ifdef __KERNEL__ #include #include #endif /* #ifdef __KERNEL__ */ #include #if !defined ( LVM_BLK_MAJOR) || !defined ( LVM_CHAR_MAJOR) #error Bad include/linux/major.h - LVM MAJOR undefined #endif #ifdef BLOCK_SIZE #undef BLOCK_SIZE #endif #ifdef CONFIG_ARCH_S390 #define BLOCK_SIZE 4096 #else #define BLOCK_SIZE 1024 #endif #ifndef SECTOR_SIZE #define SECTOR_SIZE 512 #endif /* structure version */ #define LVM_STRUCT_VERSION 1 #define LVM_DIR_PREFIX "/dev/" /* * i/o protocol version * * defined here for the driver and defined seperate in the * user land tools/lib/liblvm.h * */ #define LVM_DRIVER_IOP_VERSION 10 #define LVM_NAME "lvm" #define LVM_GLOBAL "global" #define LVM_DIR "lvm" #define LVM_VG_SUBDIR "VGs" #define LVM_LV_SUBDIR "LVs" #define LVM_PV_SUBDIR "PVs" /* * VG/LV indexing macros */ /* character minor maps directly to volume group */ #define VG_CHR(a) ( a) /* block minor indexes into a volume group/logical volume indirection table */ #define VG_BLK(a) ( vg_lv_map[a].vg_number) #define LV_BLK(a) ( vg_lv_map[a].lv_number) /* * absolute limits for VGs, PVs per VG and LVs per VG */ #define ABS_MAX_VG 99 #define ABS_MAX_PV 256 #define ABS_MAX_LV 256 /* caused by 8 bit minor */ #define MAX_VG ABS_MAX_VG #define MAX_LV ABS_MAX_LV #define MAX_PV ABS_MAX_PV #if ( MAX_VG > ABS_MAX_VG) #undef MAX_VG #define MAX_VG ABS_MAX_VG #endif #if ( MAX_LV > ABS_MAX_LV) #undef MAX_LV #define MAX_LV ABS_MAX_LV #endif /* * VGDA: default disk spaces and offsets * * there's space after the structures for later extensions. * * offset what size * --------------- ---------------------------------- ------------ * 0 physical volume structure ~500 byte * * 1K volume group structure ~200 byte * * 6K namelist of physical volumes 128 byte each * * 6k + n * ~300byte n logical volume structures ~300 byte each * * + m * 4byte m physical extent alloc. structs 4 byte each * * End of disk - first physical extent typically 4 megabyte * PE total * * PE size * * */ /* DONT TOUCH THESE !!! */ /* * LVM_PE_T_MAX corresponds to: * * 8KB PE size can map a ~512 MB logical volume at the cost of 1MB memory, * * 128MB PE size can map a 8TB logical volume at the same cost of memory. * * Default PE size of 4 MB gives a maximum logical volume size of 256 GB. * * Maximum PE size of 16GB gives a maximum logical volume size of 1024 TB. * * AFAIK, the actual kernels limit this to 1 TB. * * Should be a sufficient spectrum ;*) */ /* This is the usable size of pe_disk_t.le_num !!! v v */ #define LVM_PE_T_MAX ( ( 1 << ( sizeof ( uint16_t) * 8)) - 2) #define LVM_LV_SIZE_MAX(a) ( ( long long) LVM_PE_T_MAX * (a)->pe_size > ( long long) 1024*1024/SECTOR_SIZE*1024*1024 ? ( long long) 1024*1024/SECTOR_SIZE*1024*1024 : ( long long) LVM_PE_T_MAX * (a)->pe_size) #define LVM_MIN_PE_SIZE ( 8192L / SECTOR_SIZE) /* 8 KB in sectors */ #define LVM_MAX_PE_SIZE ( 16L * 1024L * 1024L / SECTOR_SIZE * 1024) /* 16GB in sectors */ #define LVM_DEFAULT_PE_SIZE ( 32768L * 1024 / SECTOR_SIZE) /* 32 MB in sectors */ #define LVM_DEFAULT_STRIPE_SIZE 16L /* 16 KB */ #define LVM_MIN_STRIPE_SIZE ( PAGE_SIZE/SECTOR_SIZE) /* PAGESIZE in sectors */ #define LVM_MAX_STRIPE_SIZE ( 512L * 1024 / SECTOR_SIZE) /* 512 KB in sectors */ #define LVM_MAX_STRIPES 128 /* max # of stripes */ #define LVM_MAX_SIZE ( 1024LU * 1024 / SECTOR_SIZE * 1024 * 1024) /* 1TB[sectors] */ #define LVM_MAX_MIRRORS 2 /* future use */ #define LVM_MIN_READ_AHEAD 0 /* minimum read ahead sectors */ #define LVM_DEFAULT_READ_AHEAD 1024 /* sectors for 512k scsi segments */ #define LVM_MAX_READ_AHEAD 1024 /* maximum read ahead sectors */ #define LVM_MAX_LV_IO_TIMEOUT 60 /* seconds I/O timeout (future use) */ #define LVM_PARTITION 0xfe /* LVM partition id */ #define LVM_NEW_PARTITION 0x8e /* new LVM partition id (10/09/1999) */ #define LVM_PE_SIZE_PV_SIZE_REL 5 /* max relation PV size and PE size */ #define LVM_SNAPSHOT_MAX_CHUNK 1024 /* 1024 KB */ #define LVM_SNAPSHOT_DEF_CHUNK 64 /* 64 KB */ #define LVM_SNAPSHOT_MIN_CHUNK (PAGE_SIZE/1024) /* 4 or 8 KB */ #define UNDEF -1 /* * ioctls * FIXME: the last parameter to _IO{W,R,WR} is a data type. The macro will * expand this using sizeof(), so putting "1" there is misleading * because sizeof(1) = sizeof(int) = sizeof(2) = 4 on a 32-bit machine! */ /* volume group */ #define VG_CREATE_OLD _IOW ( 0xfe, 0x00, 1) #define VG_REMOVE _IOW ( 0xfe, 0x01, 1) #define VG_EXTEND _IOW ( 0xfe, 0x03, 1) #define VG_REDUCE _IOW ( 0xfe, 0x04, 1) #define VG_STATUS _IOWR ( 0xfe, 0x05, 1) #define VG_STATUS_GET_COUNT _IOWR ( 0xfe, 0x06, 1) #define VG_STATUS_GET_NAMELIST _IOWR ( 0xfe, 0x07, 1) #define VG_SET_EXTENDABLE _IOW ( 0xfe, 0x08, 1) #define VG_RENAME _IOW ( 0xfe, 0x09, 1) /* Since 0.9beta6 */ #define VG_CREATE _IOW ( 0xfe, 0x0a, 1) /* logical volume */ #define LV_CREATE _IOW ( 0xfe, 0x20, 1) #define LV_REMOVE _IOW ( 0xfe, 0x21, 1) #define LV_ACTIVATE _IO ( 0xfe, 0x22) #define LV_DEACTIVATE _IO ( 0xfe, 0x23) #define LV_EXTEND _IOW ( 0xfe, 0x24, 1) #define LV_REDUCE _IOW ( 0xfe, 0x25, 1) #define LV_STATUS_BYNAME _IOWR ( 0xfe, 0x26, 1) #define LV_STATUS_BYINDEX _IOWR ( 0xfe, 0x27, 1) #define LV_SET_ACCESS _IOW ( 0xfe, 0x28, 1) #define LV_SET_ALLOCATION _IOW ( 0xfe, 0x29, 1) #define LV_SET_STATUS _IOW ( 0xfe, 0x2a, 1) #define LE_REMAP _IOW ( 0xfe, 0x2b, 1) #define LV_SNAPSHOT_USE_RATE _IOWR ( 0xfe, 0x2c, 1) #define LV_STATUS_BYDEV _IOWR ( 0xfe, 0x2e, 1) #define LV_RENAME _IOW ( 0xfe, 0x2f, 1) #define LV_BMAP _IOWR ( 0xfe, 0x30, 1) /* physical volume */ #define PV_STATUS _IOWR ( 0xfe, 0x40, 1) #define PV_CHANGE _IOWR ( 0xfe, 0x41, 1) #define PV_FLUSH _IOW ( 0xfe, 0x42, 1) /* physical extent */ #define PE_LOCK_UNLOCK _IOW ( 0xfe, 0x50, 1) /* i/o protocol version */ #define LVM_GET_IOP_VERSION _IOR ( 0xfe, 0x98, 1) #ifdef LVM_TOTAL_RESET /* special reset function for testing purposes */ #define LVM_RESET _IO ( 0xfe, 0x99) #endif /* lock the logical volume manager */ #if LVM_DRIVER_IOP_VERSION > 11 #define LVM_LOCK_LVM _IO ( 0xfe, 0x9A) #else /* This is actually the same as _IO ( 0xff, 0x00), oops. Remove for IOP 12+ */ #define LVM_LOCK_LVM _IO ( 0xfe, 0x100) #endif /* END ioctls */ /* * Status flags */ /* volume group */ #define VG_ACTIVE 0x01 /* vg_status */ #define VG_EXPORTED 0x02 /* " */ #define VG_EXTENDABLE 0x04 /* " */ #define VG_READ 0x01 /* vg_access */ #define VG_WRITE 0x02 /* " */ #define VG_CLUSTERED 0x04 /* " */ #define VG_SHARED 0x08 /* " */ /* logical volume */ #define LV_ACTIVE 0x01 /* lv_status */ #define LV_SPINDOWN 0x02 /* " */ #define LV_READ 0x01 /* lv_access */ #define LV_WRITE 0x02 /* " */ #define LV_SNAPSHOT 0x04 /* " */ #define LV_SNAPSHOT_ORG 0x08 /* " */ #define LV_BADBLOCK_ON 0x01 /* lv_badblock */ #define LV_STRICT 0x01 /* lv_allocation */ #define LV_CONTIGUOUS 0x02 /* " */ /* physical volume */ #define PV_ACTIVE 0x01 /* pv_status */ #define PV_ALLOCATABLE 0x02 /* pv_allocatable */ /* misc */ #define LVM_SNAPSHOT_DROPPED_SECTOR 1 /* * Structure definitions core/disk follow * * conditional conversion takes place on big endian architectures * in functions * pv_copy_*(), vg_copy_*() and lv_copy_*() * */ #define NAME_LEN 128 /* don't change!!! */ #define UUID_LEN 32 /* don't change!!! */ /* copy on write tables in disk format */ typedef struct lv_COW_table_disk_v1 { uint64_t pv_org_number; uint64_t pv_org_rsector; uint64_t pv_snap_number; uint64_t pv_snap_rsector; } lv_COW_table_disk_t; /* remap physical sector/rdev pairs including hash */ typedef struct lv_block_exception_v1 { struct list_head hash; uint32_t rsector_org; kdev_t rdev_org; uint32_t rsector_new; kdev_t rdev_new; } lv_block_exception_t; /* disk stored pe information */ typedef struct { uint16_t lv_num; uint16_t le_num; } pe_disk_t; /* disk stored PV, VG, LV and PE size and offset information */ typedef struct { uint32_t base; uint32_t size; } lvm_disk_data_t; /* * physical volume structures */ /* core */ typedef struct pv_v2 { char id[2]; /* Identifier */ unsigned short version; /* HM lvm version */ lvm_disk_data_t pv_on_disk; lvm_disk_data_t vg_on_disk; lvm_disk_data_t pv_uuidlist_on_disk; lvm_disk_data_t lv_on_disk; lvm_disk_data_t pe_on_disk; char pv_name[NAME_LEN]; char vg_name[NAME_LEN]; char system_id[NAME_LEN]; /* for vgexport/vgimport */ kdev_t pv_dev; uint pv_number; uint pv_status; uint pv_allocatable; uint pv_size; /* HM */ uint lv_cur; uint pe_size; uint pe_total; uint pe_allocated; uint pe_stale; /* for future use */ pe_disk_t *pe; /* HM */ struct block_device *bd; char pv_uuid[UUID_LEN + 1]; #ifndef __KERNEL__ uint32_t pe_start; /* in sectors */ #endif } pv_t; /* disk */ typedef struct pv_disk_v2 { uint8_t id[2]; /* Identifier */ uint16_t version; /* HM lvm version */ lvm_disk_data_t pv_on_disk; lvm_disk_data_t vg_on_disk; lvm_disk_data_t pv_uuidlist_on_disk; lvm_disk_data_t lv_on_disk; lvm_disk_data_t pe_on_disk; uint8_t pv_uuid[NAME_LEN]; uint8_t vg_name[NAME_LEN]; uint8_t system_id[NAME_LEN]; /* for vgexport/vgimport */ uint32_t pv_major; uint32_t pv_number; uint32_t pv_status; uint32_t pv_allocatable; uint32_t pv_size; /* HM */ uint32_t lv_cur; uint32_t pe_size; uint32_t pe_total; uint32_t pe_allocated; /* new in struct version 2 */ uint32_t pe_start; /* in sectors */ } pv_disk_t; /* * Structures for Logical Volume (LV) */ /* core PE information */ typedef struct { kdev_t dev; uint32_t pe; /* to be changed if > 2TB */ uint32_t reads; uint32_t writes; } pe_t; typedef struct { char lv_name[NAME_LEN]; kdev_t old_dev; kdev_t new_dev; uint32_t old_pe; uint32_t new_pe; } le_remap_req_t; typedef struct lv_bmap { uint32_t lv_block; dev_t lv_dev; } lv_bmap_t; /* * Structure Logical Volume (LV) Version 3 */ /* core */ typedef struct lv_v5 { char lv_name[NAME_LEN]; char vg_name[NAME_LEN]; uint lv_access; uint lv_status; uint lv_open; /* HM */ kdev_t lv_dev; /* HM */ uint lv_number; /* HM */ uint lv_mirror_copies; /* for future use */ uint lv_recovery; /* " */ uint lv_schedule; /* " */ uint lv_size; pe_t *lv_current_pe; /* HM */ uint lv_current_le; /* for future use */ uint lv_allocated_le; uint lv_stripes; uint lv_stripesize; uint lv_badblock; /* for future use */ uint lv_allocation; uint lv_io_timeout; /* for future use */ uint lv_read_ahead; /* delta to version 1 starts here */ struct lv_v5 *lv_snapshot_org; struct lv_v5 *lv_snapshot_prev; struct lv_v5 *lv_snapshot_next; lv_block_exception_t *lv_block_exception; uint lv_remap_ptr; uint lv_remap_end; uint lv_chunk_size; uint lv_snapshot_minor; #ifdef __KERNEL__ struct kiobuf *lv_iobuf; struct kiobuf *lv_COW_table_iobuf; struct rw_semaphore lv_lock; struct list_head *lv_snapshot_hash_table; uint32_t lv_snapshot_hash_table_size; uint32_t lv_snapshot_hash_mask; wait_queue_head_t lv_snapshot_wait; int lv_snapshot_use_rate; struct vg_v3 *vg; uint lv_allocated_snapshot_le; #else char dummy[200]; #endif } lv_t; /* disk */ typedef struct lv_disk_v3 { uint8_t lv_name[NAME_LEN]; uint8_t vg_name[NAME_LEN]; uint32_t lv_access; uint32_t lv_status; uint32_t lv_open; /* HM */ uint32_t lv_dev; /* HM */ uint32_t lv_number; /* HM */ uint32_t lv_mirror_copies; /* for future use */ uint32_t lv_recovery; /* " */ uint32_t lv_schedule; /* " */ uint32_t lv_size; uint32_t lv_snapshot_minor; /* minor number of original */ uint16_t lv_chunk_size; /* chunk size of snapshot */ uint16_t dummy; uint32_t lv_allocated_le; uint32_t lv_stripes; uint32_t lv_stripesize; uint32_t lv_badblock; /* for future use */ uint32_t lv_allocation; uint32_t lv_io_timeout; /* for future use */ uint32_t lv_read_ahead; /* HM */ } lv_disk_t; /* * Structure Volume Group (VG) Version 1 */ /* core */ typedef struct vg_v3 { char vg_name[NAME_LEN]; /* volume group name */ uint vg_number; /* volume group number */ uint vg_access; /* read/write */ uint vg_status; /* active or not */ uint lv_max; /* maximum logical volumes */ uint lv_cur; /* current logical volumes */ uint lv_open; /* open logical volumes */ uint pv_max; /* maximum physical volumes */ uint pv_cur; /* current physical volumes FU */ uint pv_act; /* active physical volumes */ uint dummy; /* was obsolete max_pe_per_pv */ uint vgda; /* volume group descriptor arrays FU */ uint pe_size; /* physical extent size in sectors */ uint pe_total; /* total of physical extents */ uint pe_allocated; /* allocated physical extents */ uint pvg_total; /* physical volume groups FU */ struct proc_dir_entry *proc; pv_t *pv[ABS_MAX_PV + 1]; /* physical volume struct pointers */ lv_t *lv[ABS_MAX_LV + 1]; /* logical volume struct pointers */ char vg_uuid[UUID_LEN + 1]; /* volume group UUID */ #ifdef __KERNEL__ struct proc_dir_entry *vg_dir_pde; struct proc_dir_entry *lv_subdir_pde; struct proc_dir_entry *pv_subdir_pde; #else char dummy1[200]; #endif } vg_t; /* disk */ typedef struct vg_disk_v2 { uint8_t vg_uuid[UUID_LEN]; /* volume group UUID */ uint8_t vg_name_dummy[NAME_LEN - UUID_LEN]; /* rest of v1 VG name */ uint32_t vg_number; /* volume group number */ uint32_t vg_access; /* read/write */ uint32_t vg_status; /* active or not */ uint32_t lv_max; /* maximum logical volumes */ uint32_t lv_cur; /* current logical volumes */ uint32_t lv_open; /* open logical volumes */ uint32_t pv_max; /* maximum physical volumes */ uint32_t pv_cur; /* current physical volumes FU */ uint32_t pv_act; /* active physical volumes */ uint32_t dummy; uint32_t vgda; /* volume group descriptor arrays FU */ uint32_t pe_size; /* physical extent size in sectors */ uint32_t pe_total; /* total of physical extents */ uint32_t pe_allocated; /* allocated physical extents */ uint32_t pvg_total; /* physical volume groups FU */ } vg_disk_t; /* * Request structures for ioctls */ /* Request structure PV_STATUS_BY_NAME... */ typedef struct { char pv_name[NAME_LEN]; pv_t *pv; } pv_status_req_t, pv_change_req_t; /* Request structure PV_FLUSH */ typedef struct { char pv_name[NAME_LEN]; kdev_t pv_dev; } pv_flush_req_t; /* Request structure PE_MOVE */ typedef struct { enum { LOCK_PE, UNLOCK_PE } lock; struct { kdev_t lv_dev; kdev_t pv_dev; uint32_t pv_offset; } data; } pe_lock_req_t; /* Request structure LV_STATUS_BYNAME */ typedef struct { char lv_name[NAME_LEN]; lv_t *lv; } lv_status_byname_req_t, lv_req_t; /* Request structure LV_STATUS_BYINDEX */ typedef struct { uint32_t lv_index; lv_t *lv; /* Transfer size because user space and kernel space differ */ ushort size; } lv_status_byindex_req_t; /* Request structure LV_STATUS_BYDEV... */ typedef struct { dev_t dev; lv_t *lv; } lv_status_bydev_req_t; /* Request structure LV_SNAPSHOT_USE_RATE */ typedef struct { int block; int rate; } lv_snapshot_use_rate_req_t; /* useful inlines */ static inline ulong round_up(ulong n, ulong size) { size--; return (n + size) & ~size; } static inline ulong div_up(ulong n, ulong size) { return round_up(n, size) / size; } /* FIXME: nasty capital letters */ static int inline LVM_GET_COW_TABLE_CHUNKS_PER_PE(vg_t * vg, lv_t * lv) { return vg->pe_size / lv->lv_chunk_size; } static int inline LVM_GET_COW_TABLE_ENTRIES_PER_PE(vg_t * vg, lv_t * lv) { ulong chunks = vg->pe_size / lv->lv_chunk_size; ulong entry_size = sizeof(lv_COW_table_disk_t); ulong chunk_size = lv->lv_chunk_size * SECTOR_SIZE; ulong entries = (vg->pe_size * SECTOR_SIZE) / (entry_size + chunk_size); if (chunks < 2) return 0; for (; entries; entries--) if ((div_up(entries * entry_size, chunk_size) + entries) <= chunks) break; return entries; } #endif /* #ifndef _LVM_H_INCLUDE */