Linux Kernel  3.7.1
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ore_raid.h
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1 /*
2  * Copyright (C) from 2011
3  * Boaz Harrosh <[email protected]>
4  *
5  * This file is part of the objects raid engine (ore).
6  *
7  * It is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as published
9  * by the Free Software Foundation.
10  *
11  * You should have received a copy of the GNU General Public License
12  * along with "ore". If not, write to the Free Software Foundation, Inc:
13  * "Free Software Foundation <[email protected]>"
14  */
15 
16 #include <scsi/osd_ore.h>
17 
18 #define ORE_ERR(fmt, a...) printk(KERN_ERR "ore: " fmt, ##a)
19 
20 #ifdef CONFIG_EXOFS_DEBUG
21 #define ORE_DBGMSG(fmt, a...) \
22  printk(KERN_NOTICE "ore @%s:%d: " fmt, __func__, __LINE__, ##a)
23 #else
24 #define ORE_DBGMSG(fmt, a...) \
25  do { if (0) printk(fmt, ##a); } while (0)
26 #endif
27 
28 /* u64 has problems with printk this will cast it to unsigned long long */
29 #define _LLU(x) (unsigned long long)(x)
30 
31 #define ORE_DBGMSG2(M...) do {} while (0)
32 /* #define ORE_DBGMSG2 ORE_DBGMSG */
33 
34 /* Calculate the component order in a stripe. eg the logical data unit
35  * address within the stripe of @dev given the @par_dev of this stripe.
36  */
37 static inline unsigned _dev_order(unsigned devs_in_group, unsigned mirrors_p1,
38  unsigned par_dev, unsigned dev)
39 {
40  unsigned first_dev = dev - dev % devs_in_group;
41 
42  dev -= first_dev;
43  par_dev -= first_dev;
44 
45  if (devs_in_group == par_dev) /* The raid 0 case */
46  return dev / mirrors_p1;
47  /* raid4/5/6 case */
48  return ((devs_in_group + dev - par_dev - mirrors_p1) % devs_in_group) /
49  mirrors_p1;
50 }
51 
52 /* ios_raid.c stuff needed by ios.c */
54 void _ore_free_raid_stuff(struct ore_io_state *ios);
55 
56 void _ore_add_sg_seg(struct ore_per_dev_state *per_dev, unsigned cur_len,
57  bool not_last);
58 int _ore_add_parity_unit(struct ore_io_state *ios, struct ore_striping_info *si,
59  struct ore_per_dev_state *per_dev, unsigned cur_len);
60 void _ore_add_stripe_page(struct __stripe_pages_2d *sp2d,
61  struct ore_striping_info *si, struct page *page);
62 static inline void _add_stripe_page(struct __stripe_pages_2d *sp2d,
63  struct ore_striping_info *si, struct page *page)
64 {
65  if (!sp2d) /* Inline the fast path */
66  return; /* Hay no raid stuff */
67  _ore_add_stripe_page(sp2d, si, page);
68 }
69 
70 /* ios.c stuff needed by ios_raid.c */
72  struct ore_components *oc, unsigned numdevs,
73  unsigned sgs_per_dev, unsigned num_par_pages,
74  struct ore_io_state **pios);
75 int _ore_add_stripe_unit(struct ore_io_state *ios, unsigned *cur_pg,
76  unsigned pgbase, struct page **pages,
77  struct ore_per_dev_state *per_dev, int cur_len);
78 int _ore_read_mirror(struct ore_io_state *ios, unsigned cur_comp);
79 int ore_io_execute(struct ore_io_state *ios);