1 /*
2  * Copyright (C) 2011
3  * Boaz Harrosh <bharrosh@panasas.com>
4  *
5  * Public Declarations of the ORE API
6  *
7  * This file is part of the ORE (Object Raid Engine) library.
8  *
9  * ORE is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as published
11  * by the Free Software Foundation. (GPL v2)
12  *
13  * ORE is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with the ORE; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
21  */
22 #ifndef __ORE_H__
23 #define __ORE_H__
24 
25 #include <scsi/osd_initiator.h>
26 #include <scsi/osd_attributes.h>
27 #include <scsi/osd_sec.h>
28 #include <linux/pnfs_osd_xdr.h>
29 
30 struct ore_comp {
31 	struct osd_obj_id	obj;
32 	u8			cred[OSD_CAP_LEN];
33 };
34 
35 struct ore_layout {
36 	/* Our way of looking at the data_map */
37 	enum pnfs_osd_raid_algorithm4
38 		 raid_algorithm;
39 	unsigned stripe_unit;
40 	unsigned mirrors_p1;
41 
42 	unsigned group_width;
43 	unsigned parity;
44 	u64	 group_depth;
45 	unsigned group_count;
46 
47 	/* Cached often needed calculations filled in by
48 	 * ore_verify_layout
49 	 */
50 	unsigned long max_io_length;	/* Max length that should be passed to
51 					 * ore_get_rw_state
52 					 */
53 };
54 
55 struct ore_dev {
56 	struct osd_dev *od;
57 };
58 
59 struct ore_components {
60 	unsigned	first_dev;		/* First logical device no    */
61 	unsigned	numdevs;		/* Num of devices in array    */
62 	/* If @single_comp == EC_SINGLE_COMP, @comps points to a single
63 	 * component. else there are @numdevs components
64 	 */
65 	enum EC_COMP_USAGE {
66 		EC_SINGLE_COMP = 0, EC_MULTPLE_COMPS = 0xffffffff
67 	}		single_comp;
68 	struct ore_comp	*comps;
69 
70 	/* Array of pointers to ore_dev-* . User will usually have these pointed
71 	 * too a bigger struct which contain an "ore_dev ored" member and use
72 	 * container_of(oc->ods[i], struct foo_dev, ored) to access the bigger
73 	 * structure.
74 	 */
75 	struct ore_dev	**ods;
76 };
77 
78 /* ore_comp_dev Recievies a logical device index */
ore_comp_dev(const struct ore_components * oc,unsigned i)79 static inline struct osd_dev *ore_comp_dev(
80 	const struct ore_components *oc, unsigned i)
81 {
82 	BUG_ON((i < oc->first_dev) || (oc->first_dev + oc->numdevs <= i));
83 	return oc->ods[i - oc->first_dev]->od;
84 }
85 
ore_comp_set_dev(struct ore_components * oc,unsigned i,struct osd_dev * od)86 static inline void ore_comp_set_dev(
87 	struct ore_components *oc, unsigned i, struct osd_dev *od)
88 {
89 	oc->ods[i - oc->first_dev]->od = od;
90 }
91 
92 struct ore_striping_info {
93 	u64 offset;
94 	u64 obj_offset;
95 	u64 length;
96 	u64 first_stripe_start; /* only used in raid writes */
97 	u64 M; /* for truncate */
98 	unsigned bytes_in_stripe;
99 	unsigned dev;
100 	unsigned par_dev;
101 	unsigned unit_off;
102 	unsigned cur_pg;
103 	unsigned cur_comp;
104 };
105 
106 struct ore_io_state;
107 typedef void (*ore_io_done_fn)(struct ore_io_state *ios, void *private);
108 struct _ore_r4w_op {
109 	/* @Priv given here is passed ios->private */
110 	struct page * (*get_page)(void *priv, u64 page_index, bool *uptodate);
111 	void (*put_page)(void *priv, struct page *page);
112 };
113 
114 struct ore_io_state {
115 	struct kref		kref;
116 	struct ore_striping_info si;
117 
118 	void			*private;
119 	ore_io_done_fn	done;
120 
121 	struct ore_layout	*layout;
122 	struct ore_components	*oc;
123 
124 	/* Global read/write IO*/
125 	loff_t			offset;
126 	unsigned long		length;
127 	void			*kern_buff;
128 
129 	struct page		**pages;
130 	unsigned		nr_pages;
131 	unsigned		pgbase;
132 	unsigned		pages_consumed;
133 
134 	/* Attributes */
135 	unsigned		in_attr_len;
136 	struct osd_attr		*in_attr;
137 	unsigned		out_attr_len;
138 	struct osd_attr		*out_attr;
139 
140 	bool			reading;
141 
142 	/* House keeping of Parity pages */
143 	bool			extra_part_alloc;
144 	struct page		**parity_pages;
145 	unsigned		max_par_pages;
146 	unsigned		cur_par_page;
147 	unsigned		sgs_per_dev;
148 	struct __stripe_pages_2d *sp2d;
149 	struct ore_io_state	 *ios_read_4_write;
150 	const struct _ore_r4w_op *r4w;
151 
152 	/* Variable array of size numdevs */
153 	unsigned numdevs;
154 	struct ore_per_dev_state {
155 		struct osd_request *or;
156 		struct bio *bio;
157 		loff_t offset;
158 		unsigned length;
159 		unsigned last_sgs_total;
160 		unsigned dev;
161 		struct osd_sg_entry *sglist;
162 		unsigned cur_sg;
163 	} per_dev[];
164 };
165 
ore_io_state_size(unsigned numdevs)166 static inline unsigned ore_io_state_size(unsigned numdevs)
167 {
168 	return sizeof(struct ore_io_state) +
169 		sizeof(struct ore_per_dev_state) * numdevs;
170 }
171 
172 /* ore.c */
173 int ore_verify_layout(unsigned total_comps, struct ore_layout *layout);
174 void ore_calc_stripe_info(struct ore_layout *layout, u64 file_offset,
175 			  u64 length, struct ore_striping_info *si);
176 int ore_get_rw_state(struct ore_layout *layout, struct ore_components *comps,
177 		     bool is_reading, u64 offset, u64 length,
178 		     struct ore_io_state **ios);
179 int ore_get_io_state(struct ore_layout *layout, struct ore_components *comps,
180 		     struct ore_io_state **ios);
181 void ore_put_io_state(struct ore_io_state *ios);
182 
183 typedef void (*ore_on_dev_error)(struct ore_io_state *ios, struct ore_dev *od,
184 	unsigned dev_index, enum osd_err_priority oep,
185 	u64 dev_offset, u64  dev_len);
186 int ore_check_io(struct ore_io_state *ios, ore_on_dev_error rep);
187 
188 int ore_create(struct ore_io_state *ios);
189 int ore_remove(struct ore_io_state *ios);
190 int ore_write(struct ore_io_state *ios);
191 int ore_read(struct ore_io_state *ios);
192 int ore_truncate(struct ore_layout *layout, struct ore_components *comps,
193 		 u64 size);
194 
195 int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr);
196 
197 extern const struct osd_attr g_attr_logical_length;
198 
199 #endif
200