1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <linux/init.h>
3*4882a593Smuzhiyun #include <linux/seq_file.h>
4*4882a593Smuzhiyun #include <linux/fs.h>
5*4882a593Smuzhiyun #include <linux/mm.h>
6*4882a593Smuzhiyun #include <linux/proc_fs.h>
7*4882a593Smuzhiyun #include <linux/slab.h>
8*4882a593Smuzhiyun #include <xen/interface/platform.h>
9*4882a593Smuzhiyun #include <asm/xen/hypercall.h>
10*4882a593Smuzhiyun #include <xen/xen-ops.h>
11*4882a593Smuzhiyun #include "xenfs.h"
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun #define XEN_KSYM_NAME_LEN 127 /* Hypervisor may have different name length */
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun struct xensyms {
17*4882a593Smuzhiyun struct xen_platform_op op;
18*4882a593Smuzhiyun char *name;
19*4882a593Smuzhiyun uint32_t namelen;
20*4882a593Smuzhiyun };
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun /* Grab next output page from the hypervisor */
xensyms_next_sym(struct xensyms * xs)23*4882a593Smuzhiyun static int xensyms_next_sym(struct xensyms *xs)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun int ret;
26*4882a593Smuzhiyun struct xenpf_symdata *symdata = &xs->op.u.symdata;
27*4882a593Smuzhiyun uint64_t symnum;
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun memset(xs->name, 0, xs->namelen);
30*4882a593Smuzhiyun symdata->namelen = xs->namelen;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun symnum = symdata->symnum;
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun ret = HYPERVISOR_platform_op(&xs->op);
35*4882a593Smuzhiyun if (ret < 0)
36*4882a593Smuzhiyun return ret;
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun /*
39*4882a593Smuzhiyun * If hypervisor's symbol didn't fit into the buffer then allocate
40*4882a593Smuzhiyun * a larger buffer and try again.
41*4882a593Smuzhiyun */
42*4882a593Smuzhiyun if (unlikely(symdata->namelen > xs->namelen)) {
43*4882a593Smuzhiyun kfree(xs->name);
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun xs->namelen = symdata->namelen;
46*4882a593Smuzhiyun xs->name = kzalloc(xs->namelen, GFP_KERNEL);
47*4882a593Smuzhiyun if (!xs->name)
48*4882a593Smuzhiyun return -ENOMEM;
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun set_xen_guest_handle(symdata->name, xs->name);
51*4882a593Smuzhiyun symdata->symnum--; /* Rewind */
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun ret = HYPERVISOR_platform_op(&xs->op);
54*4882a593Smuzhiyun if (ret < 0)
55*4882a593Smuzhiyun return ret;
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun if (symdata->symnum == symnum)
59*4882a593Smuzhiyun /* End of symbols */
60*4882a593Smuzhiyun return 1;
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun return 0;
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
xensyms_start(struct seq_file * m,loff_t * pos)65*4882a593Smuzhiyun static void *xensyms_start(struct seq_file *m, loff_t *pos)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun struct xensyms *xs = (struct xensyms *)m->private;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun xs->op.u.symdata.symnum = *pos;
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun if (xensyms_next_sym(xs))
72*4882a593Smuzhiyun return NULL;
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun return m->private;
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun
xensyms_next(struct seq_file * m,void * p,loff_t * pos)77*4882a593Smuzhiyun static void *xensyms_next(struct seq_file *m, void *p, loff_t *pos)
78*4882a593Smuzhiyun {
79*4882a593Smuzhiyun struct xensyms *xs = (struct xensyms *)m->private;
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun xs->op.u.symdata.symnum = ++(*pos);
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun if (xensyms_next_sym(xs))
84*4882a593Smuzhiyun return NULL;
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun return p;
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun
xensyms_show(struct seq_file * m,void * p)89*4882a593Smuzhiyun static int xensyms_show(struct seq_file *m, void *p)
90*4882a593Smuzhiyun {
91*4882a593Smuzhiyun struct xensyms *xs = (struct xensyms *)m->private;
92*4882a593Smuzhiyun struct xenpf_symdata *symdata = &xs->op.u.symdata;
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun seq_printf(m, "%016llx %c %s\n", symdata->address,
95*4882a593Smuzhiyun symdata->type, xs->name);
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun return 0;
98*4882a593Smuzhiyun }
99*4882a593Smuzhiyun
xensyms_stop(struct seq_file * m,void * p)100*4882a593Smuzhiyun static void xensyms_stop(struct seq_file *m, void *p)
101*4882a593Smuzhiyun {
102*4882a593Smuzhiyun }
103*4882a593Smuzhiyun
104*4882a593Smuzhiyun static const struct seq_operations xensyms_seq_ops = {
105*4882a593Smuzhiyun .start = xensyms_start,
106*4882a593Smuzhiyun .next = xensyms_next,
107*4882a593Smuzhiyun .show = xensyms_show,
108*4882a593Smuzhiyun .stop = xensyms_stop,
109*4882a593Smuzhiyun };
110*4882a593Smuzhiyun
xensyms_open(struct inode * inode,struct file * file)111*4882a593Smuzhiyun static int xensyms_open(struct inode *inode, struct file *file)
112*4882a593Smuzhiyun {
113*4882a593Smuzhiyun struct seq_file *m;
114*4882a593Smuzhiyun struct xensyms *xs;
115*4882a593Smuzhiyun int ret;
116*4882a593Smuzhiyun
117*4882a593Smuzhiyun ret = seq_open_private(file, &xensyms_seq_ops,
118*4882a593Smuzhiyun sizeof(struct xensyms));
119*4882a593Smuzhiyun if (ret)
120*4882a593Smuzhiyun return ret;
121*4882a593Smuzhiyun
122*4882a593Smuzhiyun m = file->private_data;
123*4882a593Smuzhiyun xs = (struct xensyms *)m->private;
124*4882a593Smuzhiyun
125*4882a593Smuzhiyun xs->namelen = XEN_KSYM_NAME_LEN + 1;
126*4882a593Smuzhiyun xs->name = kzalloc(xs->namelen, GFP_KERNEL);
127*4882a593Smuzhiyun if (!xs->name) {
128*4882a593Smuzhiyun seq_release_private(inode, file);
129*4882a593Smuzhiyun return -ENOMEM;
130*4882a593Smuzhiyun }
131*4882a593Smuzhiyun set_xen_guest_handle(xs->op.u.symdata.name, xs->name);
132*4882a593Smuzhiyun xs->op.cmd = XENPF_get_symbol;
133*4882a593Smuzhiyun xs->op.u.symdata.namelen = xs->namelen;
134*4882a593Smuzhiyun
135*4882a593Smuzhiyun return 0;
136*4882a593Smuzhiyun }
137*4882a593Smuzhiyun
xensyms_release(struct inode * inode,struct file * file)138*4882a593Smuzhiyun static int xensyms_release(struct inode *inode, struct file *file)
139*4882a593Smuzhiyun {
140*4882a593Smuzhiyun struct seq_file *m = file->private_data;
141*4882a593Smuzhiyun struct xensyms *xs = (struct xensyms *)m->private;
142*4882a593Smuzhiyun
143*4882a593Smuzhiyun kfree(xs->name);
144*4882a593Smuzhiyun return seq_release_private(inode, file);
145*4882a593Smuzhiyun }
146*4882a593Smuzhiyun
147*4882a593Smuzhiyun const struct file_operations xensyms_ops = {
148*4882a593Smuzhiyun .open = xensyms_open,
149*4882a593Smuzhiyun .read = seq_read,
150*4882a593Smuzhiyun .llseek = seq_lseek,
151*4882a593Smuzhiyun .release = xensyms_release
152*4882a593Smuzhiyun };
153