Date: Sun, 4 Mar 2012 14:55:38 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r232494 - head/sys/kern Message-ID: <201203041455.q24Etcmi039402@svn.freebsd.org>
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Author: kib Date: Sun Mar 4 14:55:37 2012 New Revision: 232494 URL: http://svn.freebsd.org/changeset/base/232494 Log: Instead of incomplete handling of read(2)/write(2) return values that does not fit into registers, declare that we do not support this case using CTASSERT(), and remove endianess-unsafe code to split return value into td_retval. While there, change the style of the sysctl debug.iosize_max_clamp definition. Requested by: bde MFC after: 3 weeks Modified: head/sys/kern/sys_generic.c Modified: head/sys/kern/sys_generic.c ============================================================================== --- head/sys/kern/sys_generic.c Sun Mar 4 14:51:42 2012 (r232493) +++ head/sys/kern/sys_generic.c Sun Mar 4 14:55:37 2012 (r232494) @@ -75,8 +75,14 @@ __FBSDID("$FreeBSD$"); #include <security/audit/audit.h> int iosize_max_clamp = 1; -SYSCTL_INT(_debug, OID_AUTO, iosize_max_clamp, CTLFLAG_RW, &iosize_max_clamp, 0, - "Clamp max i/o size to INT_MAX"); +SYSCTL_INT(_debug, OID_AUTO, iosize_max_clamp, CTLFLAG_RW, + &iosize_max_clamp, 0, "Clamp max i/o size to INT_MAX"); +/* + * Assert that the return value of read(2) and write(2) syscalls fits + * into a register. If not, an architecture will need to provide the + * usermode wrappers to reconstruct the result. + */ +CTASSERT(sizeof(register_t) >= sizeof(size_t)); static MALLOC_DEFINE(M_IOCTLOPS, "ioctlops", "ioctl data buffer"); static MALLOC_DEFINE(M_SELECT, "select", "select() buffer"); @@ -338,12 +344,7 @@ dofileread(td, fd, fp, auio, offset, fla ktrgenio(fd, UIO_READ, ktruio, error); } #endif -#if SSIZE_MAX > LONG_MAX - td->td_retval[1] = cnt >> (sizeof(register_t) * CHAR_BIT); - td->td_retval[0] = cnt; -#else td->td_retval[0] = cnt; -#endif return (error); } @@ -555,12 +556,7 @@ dofilewrite(td, fd, fp, auio, offset, fl ktrgenio(fd, UIO_WRITE, ktruio, error); } #endif -#if SSIZE_MAX > LONG_MAX - td->td_retval[1] = cnt >> (sizeof(register_t) * CHAR_BIT); - td->td_retval[0] = cnt; -#else td->td_retval[0] = cnt; -#endif return (error); }
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