xref: /netbsd/share/man/man9/copy.9 (revision 6550d01e)
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3.\" Copyright (c) 1996, 2002 Jason R. Thorpe.
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35.Dd August 28, 2005
36.Dt COPY 9
37.Os
38.Sh NAME
39.Nm copy ,
40.Nm copyin ,
41.Nm copyout ,
42.Nm copystr ,
43.Nm copyinstr ,
44.Nm copyoutstr
45.Nd kernel space to/from user space copy functions
46.Sh SYNOPSIS
47.In sys/types.h
48.In sys/systm.h
49.Ft int
50.Fn copyin "const void *uaddr" "void *kaddr" "size_t len"
51.Ft int
52.Fn copyout "const void *kaddr" "void *uaddr" "size_t len"
53.Ft int
54.Fn copystr "const void *kfaddr" "void *kdaddr" "size_t len" "size_t *done"
55.Ft int
56.Fn copyinstr "const void *uaddr" "void *kaddr" "size_t len" "size_t *done"
57.Ft int
58.Fn copyoutstr "const void *kaddr" "void *uaddr" "size_t len" "size_t *done"
59.Ft int
60.Fn copyin_proc "struct proc *p" "const void *uaddr" "void *kaddr" "size_t len"
61.Ft int
62.Fn copyout_proc "struct proc *p" "const void *kaddr" "void *uaddr" "size_t len"
63.Ft int
64.Fn ioctl_copyin "int ioctlflags" "const void *src" "void *dst" "size_t len"
65.Ft int
66.Fn ioctl_copyout "int ioctlflags" "const void *src" "void *dst" "size_t len"
67.Sh DESCRIPTION
68The
69.Nm
70functions are designed to copy contiguous data from one address
71to another.
72All but
73.Fn copystr
74copy data from user-space to kernel-space or vice-versa.
75.Pp
76The
77.Nm
78routines provide the following functionality:
79.Bl -tag -width "copyout_proc()"
80.It Fn copyin
81Copies
82.Fa len
83bytes of data from the user-space address
84.Fa uaddr
85in the current process to the kernel-space address
86.Fa kaddr .
87.It Fn copyout
88Copies
89.Fa len
90bytes of data from the kernel-space address
91.Fa kaddr
92to the user-space address
93.Fa uaddr
94in the current process.
95.It Fn copystr
96Copies a NUL-terminated string, at most
97.Fa len
98bytes long, from kernel-space address
99.Fa kfaddr
100to kernel-space address
101.Fa kdaddr .
102If the
103.Fa done
104argument is non-NULL,
105the number of bytes actually copied, including the terminating
106NUL, is returned in
107.Fa *done .
108.It Fn copyinstr
109Copies a NUL-terminated string, at most
110.Fa len
111bytes long, from user-space address
112.Fa uaddr
113in the current process to kernel-space address
114.Fa kaddr .
115If the
116.Fa done
117argument is non-NULL,
118the number of bytes actually copied, including the terminating
119NUL, is returned in
120.Fa *done .
121.It Fn copyoutstr
122Copies a NUL-terminated string, at most
123.Fa len
124bytes long, from kernel-space address
125.Fa kaddr
126to user-space address
127.Fa uaddr
128in the current process.
129If the
130.Fa done
131argument is non-NULL,
132the number of bytes actually copied, including the terminating
133NUL, is returned in
134.Fa *done .
135.It Fn copyin_proc
136Like
137.Fn copyin ,
138except it operates on the address space of the process
139.Fa p .
140.It Fn copyout_proc
141Like
142.Fn copyout ,
143except it operates on the address space of the process
144.Fa p .
145.It Fn ioctl_copyin
146Like
147.Fn copyin ,
148except it operates on kernel adresses when the
149.Dv FKIOCTL
150flag is passed in
151.Fa ioctlflags
152from the ioctl call.
153.It Fn ioctl_copyout
154Like
155.Fn copyout ,
156except it operates on kernel adresses when the
157.Dv FKIOCTL
158flag is passed in
159.Fa ioctlflags
160from the ioctl call.
161.El
162.Sh RETURN VALUES
163The
164.Nm
165functions return 0 on success or
166.Er EFAULT
167if a bad address is encountered.
168In addition, the
169.Fn copystr ,
170.Fn copyinstr ,
171and
172.Fn copyoutstr
173functions return
174.Er ENAMETOOLONG
175if the string is longer than
176.Fa len
177bytes.
178.Sh SEE ALSO
179.Xr fetch 9 ,
180.Xr store 9
181