1 /*
2 * 9p
3 *
4 * Copyright IBM, Corp. 2010
5 *
6 * Authors:
7 * Gautham R Shenoy <ego@in.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include "qapi/error.h"
15 #include "qemu-fsdev.h"
16 #include "qemu/queue.h"
17 #include "qemu/config-file.h"
18 #include "qemu/error-report.h"
19 #include "qemu/option.h"
20
21 /*
22 * A table to store the various file systems and their callback operations.
23 * -----------------
24 * fstype | ops
25 * -----------------
26 * local | local_ops
27 * . |
28 * . |
29 * . |
30 * . |
31 * -----------------
32 * etc
33 */
34 typedef struct FsDriverTable {
35 const char *name;
36 FileOperations *ops;
37 const char **opts;
38 } FsDriverTable;
39
40 typedef struct FsDriverListEntry {
41 FsDriverEntry fse;
42 QTAILQ_ENTRY(FsDriverListEntry) next;
43 } FsDriverListEntry;
44
45 static QTAILQ_HEAD(, FsDriverListEntry) fsdriver_entries =
46 QTAILQ_HEAD_INITIALIZER(fsdriver_entries);
47
48 #define COMMON_FS_DRIVER_OPTIONS "id", "fsdriver", "readonly"
49
50 static FsDriverTable FsDrivers[] = {
51 {
52 .name = "local",
53 .ops = &local_ops,
54 .opts = (const char * []) {
55 COMMON_FS_DRIVER_OPTIONS,
56 "security_model",
57 "path",
58 "writeout",
59 "fmode",
60 "dmode",
61 "multidevs",
62 "throttling.bps-total",
63 "throttling.bps-read",
64 "throttling.bps-write",
65 "throttling.iops-total",
66 "throttling.iops-read",
67 "throttling.iops-write",
68 "throttling.bps-total-max",
69 "throttling.bps-read-max",
70 "throttling.bps-write-max",
71 "throttling.iops-total-max",
72 "throttling.iops-read-max",
73 "throttling.iops-write-max",
74 "throttling.bps-total-max-length",
75 "throttling.bps-read-max-length",
76 "throttling.bps-write-max-length",
77 "throttling.iops-total-max-length",
78 "throttling.iops-read-max-length",
79 "throttling.iops-write-max-length",
80 "throttling.iops-size",
81 NULL
82 },
83 },
84 {
85 .name = "synth",
86 .ops = &synth_ops,
87 .opts = (const char * []) {
88 COMMON_FS_DRIVER_OPTIONS,
89 NULL
90 },
91 },
92 };
93
validate_opt(void * opaque,const char * name,const char * value,Error ** errp)94 static int validate_opt(void *opaque, const char *name, const char *value,
95 Error **errp)
96 {
97 FsDriverTable *drv = opaque;
98 const char **opt;
99
100 for (opt = drv->opts; *opt; opt++) {
101 if (!strcmp(*opt, name)) {
102 return 0;
103 }
104 }
105
106 error_setg(errp, "'%s' is invalid for fsdriver '%s'", name, drv->name);
107 return -1;
108 }
109
qemu_fsdev_add(QemuOpts * opts,Error ** errp)110 int qemu_fsdev_add(QemuOpts *opts, Error **errp)
111 {
112 int i;
113 struct FsDriverListEntry *fsle;
114 const char *fsdev_id = qemu_opts_id(opts);
115 const char *fsdriver = qemu_opt_get(opts, "fsdriver");
116 const char *writeout = qemu_opt_get(opts, "writeout");
117 bool ro = qemu_opt_get_bool(opts, "readonly", 0);
118
119 if (!fsdev_id) {
120 error_setg(errp, "fsdev: No id specified");
121 return -1;
122 }
123
124 if (fsdriver) {
125 for (i = 0; i < ARRAY_SIZE(FsDrivers); i++) {
126 if (strcmp(FsDrivers[i].name, fsdriver) == 0) {
127 break;
128 }
129 }
130
131 if (i == ARRAY_SIZE(FsDrivers)) {
132 error_setg(errp, "fsdev: fsdriver %s not found", fsdriver);
133 return -1;
134 }
135 } else {
136 error_setg(errp, "fsdev: No fsdriver specified");
137 return -1;
138 }
139
140 if (qemu_opt_foreach(opts, validate_opt, &FsDrivers[i], errp)) {
141 return -1;
142 }
143
144 fsle = g_malloc0(sizeof(*fsle));
145 fsle->fse.fsdev_id = g_strdup(fsdev_id);
146 fsle->fse.ops = FsDrivers[i].ops;
147 if (writeout) {
148 if (!strcmp(writeout, "immediate")) {
149 fsle->fse.export_flags |= V9FS_IMMEDIATE_WRITEOUT;
150 }
151 }
152 if (ro) {
153 fsle->fse.export_flags |= V9FS_RDONLY;
154 } else {
155 fsle->fse.export_flags &= ~V9FS_RDONLY;
156 }
157
158 if (fsle->fse.ops->parse_opts) {
159 if (fsle->fse.ops->parse_opts(opts, &fsle->fse, errp)) {
160 g_free(fsle->fse.fsdev_id);
161 g_free(fsle);
162 return -1;
163 }
164 }
165
166 QTAILQ_INSERT_TAIL(&fsdriver_entries, fsle, next);
167 return 0;
168 }
169
get_fsdev_fsentry(char * id)170 FsDriverEntry *get_fsdev_fsentry(char *id)
171 {
172 if (id) {
173 struct FsDriverListEntry *fsle;
174
175 QTAILQ_FOREACH(fsle, &fsdriver_entries, next) {
176 if (strcmp(fsle->fse.fsdev_id, id) == 0) {
177 return &fsle->fse;
178 }
179 }
180 }
181 return NULL;
182 }
183