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exofs.h
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1 /*
2  * Copyright (C) 2005, 2006
3  * Avishay Traeger ([email protected])
4  * Copyright (C) 2008, 2009
5  * Boaz Harrosh <[email protected]>
6  *
7  * Copyrights for code taken from ext2:
8  * Copyright (C) 1992, 1993, 1994, 1995
9  * Remy Card ([email protected])
10  * Laboratoire MASI - Institut Blaise Pascal
11  * Universite Pierre et Marie Curie (Paris VI)
12  * from
13  * linux/fs/minix/inode.c
14  * Copyright (C) 1991, 1992 Linus Torvalds
15  *
16  * This file is part of exofs.
17  *
18  * exofs is free software; you can redistribute it and/or modify
19  * it under the terms of the GNU General Public License as published by
20  * the Free Software Foundation. Since it is based on ext2, and the only
21  * valid version of GPL for the Linux kernel is version 2, the only valid
22  * version of GPL for exofs is version 2.
23  *
24  * exofs is distributed in the hope that it will be useful,
25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27  * GNU General Public License for more details.
28  *
29  * You should have received a copy of the GNU General Public License
30  * along with exofs; if not, write to the Free Software
31  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
32  */
33 #ifndef __EXOFS_H__
34 #define __EXOFS_H__
35 
36 #include <linux/fs.h>
37 #include <linux/time.h>
38 #include <linux/backing-dev.h>
39 #include <scsi/osd_ore.h>
40 
41 #include "common.h"
42 
43 #define EXOFS_ERR(fmt, a...) printk(KERN_ERR "exofs: " fmt, ##a)
44 
45 #ifdef CONFIG_EXOFS_DEBUG
46 #define EXOFS_DBGMSG(fmt, a...) \
47  printk(KERN_NOTICE "exofs @%s:%d: " fmt, __func__, __LINE__, ##a)
48 #else
49 #define EXOFS_DBGMSG(fmt, a...) \
50  do { if (0) printk(fmt, ##a); } while (0)
51 #endif
52 
53 /* u64 has problems with printk this will cast it to unsigned long long */
54 #define _LLU(x) (unsigned long long)(x)
55 
56 struct exofs_dev {
57  struct ore_dev ored;
58  unsigned did;
59  unsigned urilen;
61  struct kobject ed_kobj;
62 };
63 /*
64  * our extension to the in-memory superblock
65  */
66 struct exofs_sb_info {
67  struct backing_dev_info bdi; /* register our bdi with VFS */
68  struct exofs_sb_stats s_ess; /* Written often, pre-allocate*/
69  int s_timeout; /* timeout for OSD operations */
70  uint64_t s_nextid; /* highest object ID used */
71  uint32_t s_numfiles; /* number of files on fs */
72  spinlock_t s_next_gen_lock; /* spinlock for gen # update */
73  u32 s_next_generation; /* next gen # to use */
74  atomic_t s_curr_pending; /* number of pending commands */
75 
76  struct ore_layout layout; /* Default files layout */
77  struct ore_comp one_comp; /* id & cred of partition id=0*/
78  struct ore_components oc; /* comps for the partition */
79  struct kobject s_kobj; /* holds per-sbi kobject */
80 };
81 
82 /*
83  * our extension to the in-memory inode
84  */
85 struct exofs_i_info {
86  struct inode vfs_inode; /* normal in-memory inode */
87  wait_queue_head_t i_wq; /* wait queue for inode */
88  unsigned long i_flags; /* various atomic flags */
89  uint32_t i_data[EXOFS_IDATA];/*short symlink names and device #s*/
90  uint32_t i_dir_start_lookup; /* which page to start lookup */
91  uint64_t i_commit_size; /* the object's written length */
92  struct ore_comp one_comp; /* same component for all devices */
93  struct ore_components oc; /* inode view of the device table */
94 };
95 
96 static inline osd_id exofs_oi_objno(struct exofs_i_info *oi)
97 {
98  return oi->vfs_inode.i_ino + EXOFS_OBJ_OFF;
99 }
100 
101 /*
102  * our inode flags
103  */
104 #define OBJ_2BCREATED 0 /* object will be created soon*/
105 #define OBJ_CREATED 1 /* object has been created on the osd*/
106 
107 static inline int obj_2bcreated(struct exofs_i_info *oi)
108 {
109  return test_bit(OBJ_2BCREATED, &oi->i_flags);
110 }
111 
112 static inline void set_obj_2bcreated(struct exofs_i_info *oi)
113 {
115 }
116 
117 static inline int obj_created(struct exofs_i_info *oi)
118 {
119  return test_bit(OBJ_CREATED, &oi->i_flags);
120 }
121 
122 static inline void set_obj_created(struct exofs_i_info *oi)
123 {
124  set_bit(OBJ_CREATED, &oi->i_flags);
125 }
126 
127 int __exofs_wait_obj_created(struct exofs_i_info *oi);
128 static inline int wait_obj_created(struct exofs_i_info *oi)
129 {
130  if (likely(obj_created(oi)))
131  return 0;
132 
133  return __exofs_wait_obj_created(oi);
134 }
135 
136 /*
137  * get to our inode from the vfs inode
138  */
139 static inline struct exofs_i_info *exofs_i(struct inode *inode)
140 {
141  return container_of(inode, struct exofs_i_info, vfs_inode);
142 }
143 
144 /*
145  * Maximum count of links to a file
146  */
147 #define EXOFS_LINK_MAX 32000
148 
149 /*************************
150  * function declarations *
151  *************************/
152 
153 /* inode.c */
154 unsigned exofs_max_io_pages(struct ore_layout *layout,
155  unsigned expected_pages);
156 int exofs_setattr(struct dentry *, struct iattr *);
157 int exofs_write_begin(struct file *file, struct address_space *mapping,
158  loff_t pos, unsigned len, unsigned flags,
159  struct page **pagep, void **fsdata);
160 extern struct inode *exofs_iget(struct super_block *, unsigned long);
161 struct inode *exofs_new_inode(struct inode *, umode_t);
162 extern int exofs_write_inode(struct inode *, struct writeback_control *wbc);
163 extern void exofs_evict_inode(struct inode *);
164 
165 /* dir.c: */
166 int exofs_add_link(struct dentry *, struct inode *);
167 ino_t exofs_inode_by_name(struct inode *, struct dentry *);
168 int exofs_delete_entry(struct exofs_dir_entry *, struct page *);
169 int exofs_make_empty(struct inode *, struct inode *);
170 struct exofs_dir_entry *exofs_find_entry(struct inode *, struct dentry *,
171  struct page **);
172 int exofs_empty_dir(struct inode *);
173 struct exofs_dir_entry *exofs_dotdot(struct inode *, struct page **);
175 int exofs_set_link(struct inode *, struct exofs_dir_entry *, struct page *,
176  struct inode *);
177 
178 /* super.c */
180  const struct osd_obj_id *obj);
181 int exofs_sbi_write_stats(struct exofs_sb_info *sbi);
182 
183 /* sys.c */
184 int exofs_sysfs_init(void);
185 void exofs_sysfs_uninit(void);
186 int exofs_sysfs_sb_add(struct exofs_sb_info *sbi,
187  struct exofs_dt_device_info *dt_dev);
188 void exofs_sysfs_sb_del(struct exofs_sb_info *sbi);
189 int exofs_sysfs_odev_add(struct exofs_dev *edev,
190  struct exofs_sb_info *sbi);
191 void exofs_sysfs_dbg_print(void);
192 
193 /*********************
194  * operation vectors *
195  *********************/
196 /* dir.c: */
197 extern const struct file_operations exofs_dir_operations;
198 
199 /* file.c */
201 extern const struct file_operations exofs_file_operations;
202 
203 /* inode.c */
204 extern const struct address_space_operations exofs_aops;
205 
206 /* namei.c */
207 extern const struct inode_operations exofs_dir_inode_operations;
209 
210 /* symlink.c */
213 
214 /* exofs_init_comps will initialize an ore_components device array
215  * pointing to a single ore_comp struct, and a round-robin view
216  * of the device table.
217  * The first device of each inode is the [inode->ino % num_devices]
218  * and the rest of the devices sequentially following where the
219  * first device is after the last device.
220  * It is assumed that the global device array at @sbi is twice
221  * bigger and that the device table repeats twice.
222  * See: exofs_read_lookup_dev_table()
223  */
224 static inline void exofs_init_comps(struct ore_components *oc,
225  struct ore_comp *one_comp,
226  struct exofs_sb_info *sbi, osd_id oid)
227 {
228  unsigned dev_mod = (unsigned)oid, first_dev;
229 
230  one_comp->obj.partition = sbi->one_comp.obj.partition;
231  one_comp->obj.id = oid;
232  exofs_make_credential(one_comp->cred, &one_comp->obj);
233 
234  oc->first_dev = 0;
235  oc->numdevs = sbi->layout.group_width * sbi->layout.mirrors_p1 *
236  sbi->layout.group_count;
237  oc->single_comp = EC_SINGLE_COMP;
238  oc->comps = one_comp;
239 
240  /* Round robin device view of the table */
241  first_dev = (dev_mod * sbi->layout.mirrors_p1) % sbi->oc.numdevs;
242  oc->ods = &sbi->oc.ods[first_dev];
243 }
244 
245 #endif