1 /* 2 * linux/fs/nfs/blocklayout/blocklayout.h 3 * 4 * Module for the NFSv4.1 pNFS block layout driver. 5 * 6 * Copyright (c) 2006 The Regents of the University of Michigan. 7 * All rights reserved. 8 * 9 * Andy Adamson <andros@citi.umich.edu> 10 * Fred Isaman <iisaman@umich.edu> 11 * 12 * permission is granted to use, copy, create derivative works and 13 * redistribute this software and such derivative works for any purpose, 14 * so long as the name of the university of michigan is not used in 15 * any advertising or publicity pertaining to the use or distribution 16 * of this software without specific, written prior authorization. if 17 * the above copyright notice or any other identification of the 18 * university of michigan is included in any copy of any portion of 19 * this software, then the disclaimer below must also be included. 20 * 21 * this software is provided as is, without representation from the 22 * university of michigan as to its fitness for any purpose, and without 23 * warranty by the university of michigan of any kind, either express 24 * or implied, including without limitation the implied warranties of 25 * merchantability and fitness for a particular purpose. the regents 26 * of the university of michigan shall not be liable for any damages, 27 * including special, indirect, incidental, or consequential damages, 28 * with respect to any claim arising out or in connection with the use 29 * of the software, even if it has been or is hereafter advised of the 30 * possibility of such damages. 31 */ 32 #ifndef FS_NFS_NFS4BLOCKLAYOUT_H 33 #define FS_NFS_NFS4BLOCKLAYOUT_H 34 35 #include <linux/device-mapper.h> 36 #include <linux/nfs_fs.h> 37 #include <linux/sunrpc/rpc_pipe_fs.h> 38 39 #include "../pnfs.h" 40 41 #define PAGE_CACHE_SECTORS (PAGE_CACHE_SIZE >> SECTOR_SHIFT) 42 #define PAGE_CACHE_SECTOR_SHIFT (PAGE_CACHE_SHIFT - SECTOR_SHIFT) 43 44 struct block_mount_id { 45 spinlock_t bm_lock; /* protects list */ 46 struct list_head bm_devlist; /* holds pnfs_block_dev */ 47 }; 48 49 struct pnfs_block_dev { 50 struct list_head bm_node; 51 struct nfs4_deviceid bm_mdevid; /* associated devid */ 52 struct block_device *bm_mdev; /* meta device itself */ 53 }; 54 55 enum exstate4 { 56 PNFS_BLOCK_READWRITE_DATA = 0, 57 PNFS_BLOCK_READ_DATA = 1, 58 PNFS_BLOCK_INVALID_DATA = 2, /* mapped, but data is invalid */ 59 PNFS_BLOCK_NONE_DATA = 3 /* unmapped, it's a hole */ 60 }; 61 62 #define MY_MAX_TAGS (15) /* tag bitnums used must be less than this */ 63 64 struct my_tree { 65 sector_t mtt_step_size; /* Internal sector alignment */ 66 struct list_head mtt_stub; /* Should be a radix tree */ 67 }; 68 69 struct pnfs_inval_markings { 70 spinlock_t im_lock; 71 struct my_tree im_tree; /* Sectors that need LAYOUTCOMMIT */ 72 sector_t im_block_size; /* Server blocksize in sectors */ 73 }; 74 75 struct pnfs_inval_tracking { 76 struct list_head it_link; 77 int it_sector; 78 int it_tags; 79 }; 80 81 /* sector_t fields are all in 512-byte sectors */ 82 struct pnfs_block_extent { 83 struct kref be_refcnt; 84 struct list_head be_node; /* link into lseg list */ 85 struct nfs4_deviceid be_devid; /* FIXME: could use device cache instead */ 86 struct block_device *be_mdev; 87 sector_t be_f_offset; /* the starting offset in the file */ 88 sector_t be_length; /* the size of the extent */ 89 sector_t be_v_offset; /* the starting offset in the volume */ 90 enum exstate4 be_state; /* the state of this extent */ 91 struct pnfs_inval_markings *be_inval; /* tracks INVAL->RW transition */ 92 }; 93 94 /* Shortened extent used by LAYOUTCOMMIT */ 95 struct pnfs_block_short_extent { 96 struct list_head bse_node; 97 struct nfs4_deviceid bse_devid; 98 struct block_device *bse_mdev; 99 sector_t bse_f_offset; /* the starting offset in the file */ 100 sector_t bse_length; /* the size of the extent */ 101 }; 102 103 static inline void 104 BL_INIT_INVAL_MARKS(struct pnfs_inval_markings *marks, sector_t blocksize) 105 { 106 spin_lock_init(&marks->im_lock); 107 INIT_LIST_HEAD(&marks->im_tree.mtt_stub); 108 marks->im_block_size = blocksize; 109 marks->im_tree.mtt_step_size = min((sector_t)PAGE_CACHE_SECTORS, 110 blocksize); 111 } 112 113 enum extentclass4 { 114 RW_EXTENT = 0, /* READWRTE and INVAL */ 115 RO_EXTENT = 1, /* READ and NONE */ 116 EXTENT_LISTS = 2, 117 }; 118 119 static inline int bl_choose_list(enum exstate4 state) 120 { 121 if (state == PNFS_BLOCK_READ_DATA || state == PNFS_BLOCK_NONE_DATA) 122 return RO_EXTENT; 123 else 124 return RW_EXTENT; 125 } 126 127 struct pnfs_block_layout { 128 struct pnfs_layout_hdr bl_layout; 129 struct pnfs_inval_markings bl_inval; /* tracks INVAL->RW transition */ 130 spinlock_t bl_ext_lock; /* Protects list manipulation */ 131 struct list_head bl_extents[EXTENT_LISTS]; /* R and RW extents */ 132 struct list_head bl_commit; /* Needs layout commit */ 133 struct list_head bl_committing; /* Layout committing */ 134 unsigned int bl_count; /* entries in bl_commit */ 135 sector_t bl_blocksize; /* Server blocksize in sectors */ 136 }; 137 138 #define BLK_ID(lo) ((struct block_mount_id *)(NFS_SERVER(lo->plh_inode)->pnfs_ld_data)) 139 140 static inline struct pnfs_block_layout * 141 BLK_LO2EXT(struct pnfs_layout_hdr *lo) 142 { 143 return container_of(lo, struct pnfs_block_layout, bl_layout); 144 } 145 146 static inline struct pnfs_block_layout * 147 BLK_LSEG2EXT(struct pnfs_layout_segment *lseg) 148 { 149 return BLK_LO2EXT(lseg->pls_layout); 150 } 151 152 struct bl_dev_msg { 153 int32_t status; 154 uint32_t major, minor; 155 }; 156 157 struct bl_msg_hdr { 158 u8 type; 159 u16 totallen; /* length of entire message, including hdr itself */ 160 }; 161 162 extern struct dentry *bl_device_pipe; 163 extern wait_queue_head_t bl_wq; 164 165 #define BL_DEVICE_UMOUNT 0x0 /* Umount--delete devices */ 166 #define BL_DEVICE_MOUNT 0x1 /* Mount--create devices*/ 167 #define BL_DEVICE_REQUEST_INIT 0x0 /* Start request */ 168 #define BL_DEVICE_REQUEST_PROC 0x1 /* User level process succeeds */ 169 #define BL_DEVICE_REQUEST_ERR 0x2 /* User level process fails */ 170 171 /* blocklayoutdev.c */ 172 ssize_t bl_pipe_downcall(struct file *, const char __user *, size_t); 173 void bl_pipe_destroy_msg(struct rpc_pipe_msg *); 174 struct block_device *nfs4_blkdev_get(dev_t dev); 175 int nfs4_blkdev_put(struct block_device *bdev); 176 struct pnfs_block_dev *nfs4_blk_decode_device(struct nfs_server *server, 177 struct pnfs_device *dev); 178 int nfs4_blk_process_layoutget(struct pnfs_layout_hdr *lo, 179 struct nfs4_layoutget_res *lgr, gfp_t gfp_flags); 180 181 /* blocklayoutdm.c */ 182 void bl_free_block_dev(struct pnfs_block_dev *bdev); 183 184 /* extents.c */ 185 struct pnfs_block_extent * 186 bl_find_get_extent(struct pnfs_block_layout *bl, sector_t isect, 187 struct pnfs_block_extent **cow_read); 188 int bl_mark_sectors_init(struct pnfs_inval_markings *marks, 189 sector_t offset, sector_t length, 190 sector_t **pages); 191 void bl_put_extent(struct pnfs_block_extent *be); 192 struct pnfs_block_extent *bl_alloc_extent(void); 193 int bl_is_sector_init(struct pnfs_inval_markings *marks, sector_t isect); 194 int encode_pnfs_block_layoutupdate(struct pnfs_block_layout *bl, 195 struct xdr_stream *xdr, 196 const struct nfs4_layoutcommit_args *arg); 197 void clean_pnfs_block_layoutupdate(struct pnfs_block_layout *bl, 198 const struct nfs4_layoutcommit_args *arg, 199 int status); 200 int bl_add_merge_extent(struct pnfs_block_layout *bl, 201 struct pnfs_block_extent *new); 202 int bl_mark_for_commit(struct pnfs_block_extent *be, 203 sector_t offset, sector_t length); 204 205 #endif /* FS_NFS_NFS4BLOCKLAYOUT_H */ 206