The branch main has been updated by 0mp: URL: https://cgit.FreeBSD.org/src/commit/?id=076e44839160f74f96fda83fa81c3acb41b9ebc8
commit 076e44839160f74f96fda83fa81c3acb41b9ebc8 Author: Mateusz Piotrowski <[email protected]> AuthorDate: 2026-03-20 07:52:28 +0000 Commit: Mateusz Piotrowski <[email protected]> CommitDate: 2026-05-08 09:05:57 +0000 uio.9: Document uiomove_fromphys() Reviewed by: kib Discussed with: markj, royger MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D54070 --- share/man/man9/Makefile | 1 + share/man/man9/uio.9 | 45 ++++++++++++++++++++++++++++++++++----------- 2 files changed, 35 insertions(+), 11 deletions(-) diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile index 29c822c10eb2..fbb981891ce4 100644 --- a/share/man/man9/Makefile +++ b/share/man/man9/Makefile @@ -2333,6 +2333,7 @@ MLINKS+=uidinfo.9 uifind.9 \ uidinfo.9 uihold.9 MLINKS+=uio.9 uiomove.9 \ uio.9 uiomove_frombuf.9 \ + uio.9 uiomove_fromphys.9 \ uio.9 uiomove_nofault.9 MLINKS+=unr.9 alloc_unr.9 \ unr.9 alloc_unrl.9 \ diff --git a/share/man/man9/uio.9 b/share/man/man9/uio.9 index b143eb6e8e62..a7563125a351 100644 --- a/share/man/man9/uio.9 +++ b/share/man/man9/uio.9 @@ -23,13 +23,14 @@ .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" -.Dd October 22, 2025 +.Dd May 7, 2026 .Dt UIO 9 .Os .Sh NAME .Nm uio , .Nm uiomove , .Nm uiomove_frombuf , +.Nm uiomove_fromphys , .Nm uiomove_nofault .Nd device driver I/O routines .Sh SYNOPSIS @@ -37,25 +38,29 @@ .In sys/uio.h .Bd -literal struct uio { - struct iovec *uio_iov; /* scatter/gather list */ - int uio_iovcnt; /* length of scatter/gather list */ - off_t uio_offset; /* offset in target object */ - ssize_t uio_resid; /* remaining bytes to copy */ - enum uio_seg uio_segflg; /* address space */ - enum uio_rw uio_rw; /* operation */ - struct thread *uio_td; /* owner */ + struct iovec *uio_iov; /* scatter/gather list */ + int uio_iovcnt; /* length of scatter/gather list */ + off_t uio_offset; /* offset in target object */ + ssize_t uio_resid; /* remaining bytes to process */ + enum uio_seg uio_segflg; /* address space */ + enum uio_rw uio_rw; /* operation */ + struct thread *uio_td; /* owner */ }; .Ed +.Pp .Ft int .Fn uiomove "void *buf" "int howmuch" "struct uio *uiop" .Ft int .Fn uiomove_frombuf "void *buf" "int howmuch" "struct uio *uiop" .Ft int +.Fn uiomove_fromphys "vm_page_t ma[]" "vm_offset_t offset" "int howmuch" "struct uio *uiop" +.Ft int .Fn uiomove_nofault "void *buf" "int howmuch" "struct uio *uiop" .Sh DESCRIPTION The functions .Fn uiomove , .Fn uiomove_frombuf , +.Fn uiomove_fromphys , and .Fn uiomove_nofault are used to transfer data between buffers and I/O vectors that might @@ -152,10 +157,27 @@ When .Va uio_offset is greater than or equal to the buffer size, the result is success with no bytes transferred, effectively signaling EOF. +.Pp +The +.Fn uiomove_fromphys +function provides a machine-independent way to copy memory +to and from the physical address space. +The +.Fa "ma[]" +argument is an array of physical pages. +Every physical page address in the array provides +a page-sized chunk of the physical space. +The +.Fa "offset" +argument is the offset into the +.Fa "ma[]" +array. +In particular, the offset does not have to lie within the first page. .Sh RETURN VALUES On success .Fn uiomove , .Fn uiomove_frombuf , +.Fn uiomove_fromphys , and .Fn uiomove_nofault will return 0; on error they will return an appropriate error code. @@ -168,7 +190,7 @@ will not work (the buffer pointer is not being advanced in case of a partial read), it is just here to demonstrate the .Nm handling. -.Bd -literal +.Bd -literal -offset 2n /* MIN() can be found there: */ #include <sys/param.h> @@ -200,7 +222,8 @@ fooread(struct cdev *dev, struct uio *uio, int flag) } .Ed .Sh ERRORS -.Fn uiomove +.Fn uiomove , +.Fn uiomove_fromphys and .Fn uiomove_nofault will fail and return the following error code if: @@ -211,7 +234,7 @@ The invoked or .Xr copyout 9 returned -.Er EFAULT +.Er EFAULT . .El .Pp In addition,
