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Diffstat (limited to 'share/man/man9/fetch.9')
| -rw-r--r-- | share/man/man9/fetch.9 | 72 |
1 files changed, 60 insertions, 12 deletions
diff --git a/share/man/man9/fetch.9 b/share/man/man9/fetch.9 index ccf6866..1d46784 100644 --- a/share/man/man9/fetch.9 +++ b/share/man/man9/fetch.9 @@ -34,7 +34,7 @@ .\" .\" $FreeBSD$ .\" -.Dd October 5, 2009 +.Dd October 29, 2014 .Dt FETCH 9 .Os .Sh NAME @@ -44,43 +44,56 @@ .Nm fuword , .Nm fuword16 , .Nm fuword32 , -.Nm fuword64 +.Nm fuword64 , +.Nm fueword , +.Nm fueword32 , +.Nm fueword64 .Nd fetch data from user-space .Sh SYNOPSIS .In sys/types.h -.In sys/time.h .In sys/systm.h .Ft int -.Fn fubyte "const void *base" +.Fn fubyte "volatile const void *base" .Ft long -.Fn fuword "const void *base" +.Fn fuword "volatile const void *base" .Ft int -.Fn fuword16 "void *base" +.Fn fuword16 "volatile const void *base" .Ft int32_t -.Fn fuword32 "const void *base" +.Fn fuword32 "volatile const void *base" .Ft int64_t -.Fn fuword64 "const void *base" +.Fn fuword64 "volatile const void *base" +.Ft long +.Fn fueword "volatile const void *base" "long *val" +.Ft int32_t +.Fn fueword32 "volatile const void *base" "int32_t *val" +.Ft int64_t +.Fn fueword64 "volatile const void *base" "int64_t *val" .In sys/resourcevar.h .Ft int .Fn fuswintr "void *base" .Sh DESCRIPTION The .Nm -functions are designed to copy small amounts of data from user-space. +functions are designed to copy small amounts of data from user-space +of the current process. +If read is successful, it is performed atomically. +The data read must be naturally aligned. .Pp The .Nm routines provide the following functionality: -.Bl -tag -width "fuswintr()" +.Bl -tag -width "fueword32()" .It Fn fubyte Fetches a byte of data from the user-space address .Pa base . +The byte read is zero-extended into the results variable. .It Fn fuword -Fetches a word of data from the user-space address +Fetches a word of data (long) from the user-space address .Pa base . .It Fn fuword16 Fetches 16 bits of data from the user-space address .Pa base . +The half-word read is zero-extended into the results variable. .It Fn fuword32 Fetches 32 bits of data from the user-space address .Pa base . @@ -91,11 +104,46 @@ Fetches 64 bits of data from the user-space address Fetches a short word of data from the user-space address .Pa base . This function is safe to call during an interrupt context. +.It Fn fueword +Fetches a word of data (long) from the user-space address +.Pa base +and stores the result in the variable pointed by +.Pa val . +.It Fn fueword32 +Fetches 32 bits of data from the user-space address +.Pa base +and stores the result in the variable pointed by +.Pa val . +.It Fn fueword64 +Fetches 64 bits of data from the user-space address +.Pa base +and stores the result in the variable pointed by +.Pa val . .El +.Pp +The callers of +.Fn fuword , +.Fn fuword32 +and +.Fn fuword64 +functions cannot distinguish between -1 read from +userspace and function failure. .Sh RETURN VALUES The -.Nm +.Fn fubyte , +.Fn fuword , +.Fn fuword16 , +.Fn fuword32 , +.Fn fuword64 , +and +.Fn fuswintr functions return the data fetched or -1 on failure. +The +.Fn fueword , +.Fn fueword32 +and +.Fn fueword64 +functions return 0 on success and -1 on failure. .Sh SEE ALSO .Xr copy 9 , .Xr store 9 |
