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 #include <linux/bug.h>
30 
31 struct ore_comp {
32 	struct osd_obj_id	obj;
33 	u8			cred[OSD_CAP_LEN];
34 };
35 
36 struct ore_layout {
37 	/* Our way of looking at the data_map */
38 	enum pnfs_osd_raid_algorithm4
39 		 raid_algorithm;
40 	unsigned stripe_unit;
41 	unsigned mirrors_p1;
42 
43 	unsigned group_width;
44 	unsigned parity;
45 	u64	 group_depth;
46 	unsigned group_count;
47 
48 	/* Cached often needed calculations filled in by
49 	 * ore_verify_layout
50 	 */
51 	unsigned long max_io_length;	/* Max length that should be passed to
52 					 * ore_get_rw_state
53 					 */
54 };
55 
56 struct ore_dev {
57 	struct osd_dev *od;
58 };
59 
60 struct ore_components {
61 	unsigned	first_dev;		/* First logical device no    */
62 	unsigned	numdevs;		/* Num of devices in array    */
63 	/* If @single_comp == EC_SINGLE_COMP, @comps points to a single
64 	 * component. else there are @numdevs components
65 	 */
66 	enum EC_COMP_USAGE {
67 		EC_SINGLE_COMP = 0, EC_MULTPLE_COMPS = 0xffffffff
68 	}		single_comp;
69 	struct ore_comp	*comps;
70 
71 	/* Array of pointers to ore_dev-* . User will usually have these pointed
72 	 * too a bigger struct which contain an "ore_dev ored" member and use
73 	 * container_of(oc->ods[i], struct foo_dev, ored) to access the bigger
74 	 * structure.
75 	 */
76 	struct ore_dev	**ods;
77 };
78 
79 /* ore_comp_dev Recievies a logical device index */
ore_comp_dev(const struct ore_components * oc,unsigned i)80 static inline struct osd_dev *ore_comp_dev(
81 	const struct ore_components *oc, unsigned i)
82 {
83 	BUG_ON((i < oc->first_dev) || (oc->first_dev + oc->numdevs <= i));
84 	return oc->ods[i - oc->first_dev]->od;
85 }
86 
ore_comp_set_dev(struct ore_components * oc,unsigned i,struct osd_dev * od)87 static inline void ore_comp_set_dev(
88 	struct ore_components *oc, unsigned i, struct osd_dev *od)
89 {
90 	oc->ods[i - oc->first_dev]->od = od;
91 }
92 
93 struct ore_striping_info {
94 	u64 offset;
95 	u64 obj_offset;
96 	u64 length;
97 	u64 first_stripe_start; /* only used in raid writes */
98 	u64 M; /* for truncate */
99 	unsigned bytes_in_stripe;
100 	unsigned dev;
101 	unsigned par_dev;
102 	unsigned unit_off;
103 	unsigned cur_pg;
104 	unsigned cur_comp;
105 	unsigned maxdevUnits;
106 };
107 
108 struct ore_io_state;
109 typedef void (*ore_io_done_fn)(struct ore_io_state *ios, void *private);
110 struct _ore_r4w_op {
111 	/* @Priv given here is passed ios->private */
112 	struct page * (*get_page)(void *priv, u64 page_index, bool *uptodate);
113 	void (*put_page)(void *priv, struct page *page);
114 };
115 
116 struct ore_io_state {
117 	struct kref		kref;
118 	struct ore_striping_info si;
119 
120 	void			*private;
121 	ore_io_done_fn	done;
122 
123 	struct ore_layout	*layout;
124 	struct ore_components	*oc;
125 
126 	/* Global read/write IO*/
127 	loff_t			offset;
128 	unsigned long		length;
129 	void			*kern_buff;
130 
131 	struct page		**pages;
132 	unsigned		nr_pages;
133 	unsigned		pgbase;
134 	unsigned		pages_consumed;
135 
136 	/* Attributes */
137 	unsigned		in_attr_len;
138 	struct osd_attr		*in_attr;
139 	unsigned		out_attr_len;
140 	struct osd_attr		*out_attr;
141 
142 	bool			reading;
143 
144 	/* House keeping of Parity pages */
145 	bool			extra_part_alloc;
146 	struct page		**parity_pages;
147 	unsigned		max_par_pages;
148 	unsigned		cur_par_page;
149 	unsigned		sgs_per_dev;
150 	struct __stripe_pages_2d *sp2d;
151 	struct ore_io_state	 *ios_read_4_write;
152 	const struct _ore_r4w_op *r4w;
153 
154 	/* Variable array of size numdevs */
155 	unsigned numdevs;
156 	struct ore_per_dev_state {
157 		struct osd_request *or;
158 		struct bio *bio;
159 		loff_t offset;
160 		unsigned length;
161 		unsigned last_sgs_total;
162 		unsigned dev;
163 		struct osd_sg_entry *sglist;
164 		unsigned cur_sg;
165 	} per_dev[];
166 };
167 
ore_io_state_size(unsigned numdevs)168 static inline unsigned ore_io_state_size(unsigned numdevs)
169 {
170 	return sizeof(struct ore_io_state) +
171 		sizeof(struct ore_per_dev_state) * numdevs;
172 }
173 
174 /* ore.c */
175 int ore_verify_layout(unsigned total_comps, struct ore_layout *layout);
176 void ore_calc_stripe_info(struct ore_layout *layout, u64 file_offset,
177 			  u64 length, struct ore_striping_info *si);
178 int ore_get_rw_state(struct ore_layout *layout, struct ore_components *comps,
179 		     bool is_reading, u64 offset, u64 length,
180 		     struct ore_io_state **ios);
181 int ore_get_io_state(struct ore_layout *layout, struct ore_components *comps,
182 		     struct ore_io_state **ios);
183 void ore_put_io_state(struct ore_io_state *ios);
184 
185 typedef void (*ore_on_dev_error)(struct ore_io_state *ios, struct ore_dev *od,
186 	unsigned dev_index, enum osd_err_priority oep,
187 	u64 dev_offset, u64  dev_len);
188 int ore_check_io(struct ore_io_state *ios, ore_on_dev_error rep);
189 
190 int ore_create(struct ore_io_state *ios);
191 int ore_remove(struct ore_io_state *ios);
192 int ore_write(struct ore_io_state *ios);
193 int ore_read(struct ore_io_state *ios);
194 int ore_truncate(struct ore_layout *layout, struct ore_components *comps,
195 		 u64 size);
196 
197 int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr);
198 
199 extern const struct osd_attr g_attr_logical_length;
200 
201 #endif
202