Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751826AbaKKVKD (ORCPT ); Tue, 11 Nov 2014 16:10:03 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49458 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751347AbaKKVJ7 (ORCPT ); Tue, 11 Nov 2014 16:09:59 -0500 From: Jeff Moyer To: Milosz Tanski Cc: linux-kernel@vger.kernel.org, Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, Mel Gorman , Volker Lendecke , Tejun Heo , "Theodore Ts'o" , Al Viro , linux-api@vger.kernel.org, Michael Kerrisk , linux-arch@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v6 2/7] vfs: Define new syscalls preadv2,pwritev2 References: <0a8539257086c2a3f7615d35ef621c7f81df52cf.1415636409.git.milosz@adfin.com> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Tue, 11 Nov 2014 16:09:11 -0500 In-Reply-To: <0a8539257086c2a3f7615d35ef621c7f81df52cf.1415636409.git.milosz@adfin.com> (Milosz Tanski's message of "Mon, 10 Nov 2014 11:40:25 -0500") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Milosz Tanski writes: > New syscalls that take an flag argument. This change does not add any specific > flags. Looks good. Reviewed-by: Jeff Moyer > > Signed-off-by: Milosz Tanski > Reviewed-by: Christoph Hellwig > --- > fs/read_write.c | 172 ++++++++++++++++++++++++++++++-------- > include/linux/compat.h | 6 ++ > include/linux/syscalls.h | 6 ++ > include/uapi/asm-generic/unistd.h | 6 +- > mm/filemap.c | 5 +- > 5 files changed, 156 insertions(+), 39 deletions(-) > > diff --git a/fs/read_write.c b/fs/read_write.c > index 94b2d34..b1b4bc8 100644 > --- a/fs/read_write.c > +++ b/fs/read_write.c > @@ -866,6 +866,8 @@ ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, > return -EBADF; > if (!(file->f_mode & FMODE_CAN_READ)) > return -EINVAL; > + if (flags & ~0) > + return -EINVAL; > > return do_readv_writev(READ, file, vec, vlen, pos, flags); > } > @@ -879,21 +881,23 @@ ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, > return -EBADF; > if (!(file->f_mode & FMODE_CAN_WRITE)) > return -EINVAL; > + if (flags & ~0) > + return -EINVAL; > > return do_readv_writev(WRITE, file, vec, vlen, pos, flags); > } > > EXPORT_SYMBOL(vfs_writev); > > -SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, > - unsigned long, vlen) > +static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec, > + unsigned long vlen, int flags) > { > struct fd f = fdget_pos(fd); > ssize_t ret = -EBADF; > > if (f.file) { > loff_t pos = file_pos_read(f.file); > - ret = vfs_readv(f.file, vec, vlen, &pos, 0); > + ret = vfs_readv(f.file, vec, vlen, &pos, flags); > if (ret >= 0) > file_pos_write(f.file, pos); > fdput_pos(f); > @@ -905,15 +909,15 @@ SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, > return ret; > } > > -SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, > - unsigned long, vlen) > +static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec, > + unsigned long vlen, int flags) > { > struct fd f = fdget_pos(fd); > ssize_t ret = -EBADF; > > if (f.file) { > loff_t pos = file_pos_read(f.file); > - ret = vfs_writev(f.file, vec, vlen, &pos, 0); > + ret = vfs_writev(f.file, vec, vlen, &pos, flags); > if (ret >= 0) > file_pos_write(f.file, pos); > fdput_pos(f); > @@ -931,10 +935,9 @@ static inline loff_t pos_from_hilo(unsigned long high, unsigned long low) > return (((loff_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; > } > > -SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, > - unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) > +static ssize_t do_preadv(unsigned long fd, const struct iovec __user *vec, > + unsigned long vlen, loff_t pos, int flags) > { > - loff_t pos = pos_from_hilo(pos_h, pos_l); > struct fd f; > ssize_t ret = -EBADF; > > @@ -945,7 +948,7 @@ SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, > if (f.file) { > ret = -ESPIPE; > if (f.file->f_mode & FMODE_PREAD) > - ret = vfs_readv(f.file, vec, vlen, &pos, 0); > + ret = vfs_readv(f.file, vec, vlen, &pos, flags); > fdput(f); > } > > @@ -955,10 +958,9 @@ SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, > return ret; > } > > -SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, > - unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) > +static ssize_t do_pwritev(unsigned long fd, const struct iovec __user *vec, > + unsigned long vlen, loff_t pos, int flags) > { > - loff_t pos = pos_from_hilo(pos_h, pos_l); > struct fd f; > ssize_t ret = -EBADF; > > @@ -969,7 +971,7 @@ SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, > if (f.file) { > ret = -ESPIPE; > if (f.file->f_mode & FMODE_PWRITE) > - ret = vfs_writev(f.file, vec, vlen, &pos, 0); > + ret = vfs_writev(f.file, vec, vlen, &pos, flags); > fdput(f); > } > > @@ -979,11 +981,63 @@ SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, > return ret; > } > > +SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, > + unsigned long, vlen) > +{ > + return do_readv(fd, vec, vlen, 0); > +} > + > +SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, > + unsigned long, vlen) > +{ > + return do_writev(fd, vec, vlen, 0); > +} > + > +SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, > + unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) > +{ > + loff_t pos = pos_from_hilo(pos_h, pos_l); > + > + return do_preadv(fd, vec, vlen, pos, 0); > +} > + > +SYSCALL_DEFINE6(preadv2, unsigned long, fd, const struct iovec __user *, vec, > + unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h, > + int, flags) > +{ > + loff_t pos = pos_from_hilo(pos_h, pos_l); > + > + if (pos == -1) > + return do_readv(fd, vec, vlen, flags); > + > + return do_preadv(fd, vec, vlen, pos, flags); > +} > + > +SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, > + unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h) > +{ > + loff_t pos = pos_from_hilo(pos_h, pos_l); > + > + return do_pwritev(fd, vec, vlen, pos, 0); > +} > + > +SYSCALL_DEFINE6(pwritev2, unsigned long, fd, const struct iovec __user *, vec, > + unsigned long, vlen, unsigned long, pos_l, unsigned long, pos_h, > + int, flags) > +{ > + loff_t pos = pos_from_hilo(pos_h, pos_l); > + > + if (pos == -1) > + return do_writev(fd, vec, vlen, flags); > + > + return do_pwritev(fd, vec, vlen, pos, flags); > +} > + > #ifdef CONFIG_COMPAT > > static ssize_t compat_do_readv_writev(int type, struct file *file, > const struct compat_iovec __user *uvector, > - unsigned long nr_segs, loff_t *pos) > + unsigned long nr_segs, loff_t *pos, int flags) > { > compat_ssize_t tot_len; > struct iovec iovstack[UIO_FASTIOV]; > @@ -1017,7 +1071,7 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, > > if (iter_fn) > ret = do_iter_readv_writev(file, type, iov, nr_segs, tot_len, > - pos, iter_fn, 0); > + pos, iter_fn, flags); > else if (fnv) > ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, > pos, fnv); > @@ -1041,7 +1095,7 @@ out: > > static size_t compat_readv(struct file *file, > const struct compat_iovec __user *vec, > - unsigned long vlen, loff_t *pos) > + unsigned long vlen, loff_t *pos, int flags) > { > ssize_t ret = -EBADF; > > @@ -1051,8 +1105,10 @@ static size_t compat_readv(struct file *file, > ret = -EINVAL; > if (!(file->f_mode & FMODE_CAN_READ)) > goto out; > + if (flags & ~0) > + goto out; > > - ret = compat_do_readv_writev(READ, file, vec, vlen, pos); > + ret = compat_do_readv_writev(READ, file, vec, vlen, pos, flags); > > out: > if (ret > 0) > @@ -1061,9 +1117,9 @@ out: > return ret; > } > > -COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, > - const struct compat_iovec __user *,vec, > - compat_ulong_t, vlen) > +static size_t __compat_sys_readv(compat_ulong_t fd, > + const struct compat_iovec __user *vec, > + compat_ulong_t vlen, int flags) > { > struct fd f = fdget_pos(fd); > ssize_t ret; > @@ -1072,16 +1128,24 @@ COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, > if (!f.file) > return -EBADF; > pos = f.file->f_pos; > - ret = compat_readv(f.file, vec, vlen, &pos); > + ret = compat_readv(f.file, vec, vlen, &pos, flags); > if (ret >= 0) > f.file->f_pos = pos; > fdput_pos(f); > return ret; > + > +} > + > +COMPAT_SYSCALL_DEFINE3(readv, compat_ulong_t, fd, > + const struct compat_iovec __user *,vec, > + compat_ulong_t, vlen) > +{ > + return __compat_sys_readv(fd, vec, vlen, 0); > } > > static long __compat_sys_preadv64(unsigned long fd, > const struct compat_iovec __user *vec, > - unsigned long vlen, loff_t pos) > + unsigned long vlen, loff_t pos, int flags) > { > struct fd f; > ssize_t ret; > @@ -1093,7 +1157,7 @@ static long __compat_sys_preadv64(unsigned long fd, > return -EBADF; > ret = -ESPIPE; > if (f.file->f_mode & FMODE_PREAD) > - ret = compat_readv(f.file, vec, vlen, &pos); > + ret = compat_readv(f.file, vec, vlen, &pos, flags); > fdput(f); > return ret; > } > @@ -1103,7 +1167,7 @@ COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, > const struct compat_iovec __user *,vec, > unsigned long, vlen, loff_t, pos) > { > - return __compat_sys_preadv64(fd, vec, vlen, pos); > + return __compat_sys_preadv64(fd, vec, vlen, pos, 0); > } > #endif > > @@ -1113,12 +1177,25 @@ COMPAT_SYSCALL_DEFINE5(preadv, compat_ulong_t, fd, > { > loff_t pos = ((loff_t)pos_high << 32) | pos_low; > > - return __compat_sys_preadv64(fd, vec, vlen, pos); > + return __compat_sys_preadv64(fd, vec, vlen, pos, 0); > +} > + > +COMPAT_SYSCALL_DEFINE6(preadv2, compat_ulong_t, fd, > + const struct compat_iovec __user *,vec, > + compat_ulong_t, vlen, u32, pos_low, u32, pos_high, > + int, flags) > +{ > + loff_t pos = ((loff_t)pos_high << 32) | pos_low; > + > + if (pos == -1) > + return __compat_sys_readv(fd, vec, vlen, flags); > + > + return __compat_sys_preadv64(fd, vec, vlen, pos, flags); > } > > static size_t compat_writev(struct file *file, > const struct compat_iovec __user *vec, > - unsigned long vlen, loff_t *pos) > + unsigned long vlen, loff_t *pos, int flags) > { > ssize_t ret = -EBADF; > > @@ -1128,8 +1205,10 @@ static size_t compat_writev(struct file *file, > ret = -EINVAL; > if (!(file->f_mode & FMODE_CAN_WRITE)) > goto out; > + if (flags & ~0) > + goto out; > > - ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos); > + ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos, flags); > > out: > if (ret > 0) > @@ -1138,9 +1217,9 @@ out: > return ret; > } > > -COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, > - const struct compat_iovec __user *, vec, > - compat_ulong_t, vlen) > +static size_t __compat_sys_writev(compat_ulong_t fd, > + const struct compat_iovec __user* vec, > + compat_ulong_t vlen, int flags) > { > struct fd f = fdget_pos(fd); > ssize_t ret; > @@ -1149,28 +1228,36 @@ COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, > if (!f.file) > return -EBADF; > pos = f.file->f_pos; > - ret = compat_writev(f.file, vec, vlen, &pos); > + ret = compat_writev(f.file, vec, vlen, &pos, flags); > if (ret >= 0) > f.file->f_pos = pos; > fdput_pos(f); > return ret; > } > > +COMPAT_SYSCALL_DEFINE3(writev, compat_ulong_t, fd, > + const struct compat_iovec __user *, vec, > + compat_ulong_t, vlen) > +{ > + return __compat_sys_writev(fd, vec, vlen, 0); > +} > + > static long __compat_sys_pwritev64(unsigned long fd, > const struct compat_iovec __user *vec, > - unsigned long vlen, loff_t pos) > + unsigned long vlen, loff_t pos, int flags) > { > struct fd f; > ssize_t ret; > > if (pos < 0) > return -EINVAL; > + > f = fdget(fd); > if (!f.file) > return -EBADF; > ret = -ESPIPE; > if (f.file->f_mode & FMODE_PWRITE) > - ret = compat_writev(f.file, vec, vlen, &pos); > + ret = compat_writev(f.file, vec, vlen, &pos, flags); > fdput(f); > return ret; > } > @@ -1180,7 +1267,7 @@ COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, > const struct compat_iovec __user *,vec, > unsigned long, vlen, loff_t, pos) > { > - return __compat_sys_pwritev64(fd, vec, vlen, pos); > + return __compat_sys_pwritev64(fd, vec, vlen, pos, 0); > } > #endif > > @@ -1190,8 +1277,21 @@ COMPAT_SYSCALL_DEFINE5(pwritev, compat_ulong_t, fd, > { > loff_t pos = ((loff_t)pos_high << 32) | pos_low; > > - return __compat_sys_pwritev64(fd, vec, vlen, pos); > + return __compat_sys_pwritev64(fd, vec, vlen, pos, 0); > +} > + > +COMPAT_SYSCALL_DEFINE6(pwritev2, compat_ulong_t, fd, > + const struct compat_iovec __user *,vec, > + compat_ulong_t, vlen, u32, pos_low, u32, pos_high, int, flags) > +{ > + loff_t pos = ((loff_t)pos_high << 32) | pos_low; > + > + if (pos == -1) > + return __compat_sys_writev(fd, vec, vlen, flags); > + > + return __compat_sys_pwritev64(fd, vec, vlen, pos, flags); > } > + > #endif > > static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, > diff --git a/include/linux/compat.h b/include/linux/compat.h > index e649426..63a94e2 100644 > --- a/include/linux/compat.h > +++ b/include/linux/compat.h > @@ -340,6 +340,12 @@ asmlinkage ssize_t compat_sys_preadv(compat_ulong_t fd, > asmlinkage ssize_t compat_sys_pwritev(compat_ulong_t fd, > const struct compat_iovec __user *vec, > compat_ulong_t vlen, u32 pos_low, u32 pos_high); > +asmlinkage ssize_t compat_sys_preadv2(compat_ulong_t fd, > + const struct compat_iovec __user *vec, > + compat_ulong_t vlen, u32 pos_low, u32 pos_high, int flags); > +asmlinkage ssize_t compat_sys_pwritev2(compat_ulong_t fd, > + const struct compat_iovec __user *vec, > + compat_ulong_t vlen, u32 pos_low, u32 pos_high, int flags); > > #ifdef __ARCH_WANT_COMPAT_SYS_PREADV64 > asmlinkage long compat_sys_preadv64(unsigned long fd, > diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h > index bda9b81..cedc22e 100644 > --- a/include/linux/syscalls.h > +++ b/include/linux/syscalls.h > @@ -571,8 +571,14 @@ asmlinkage long sys_pwrite64(unsigned int fd, const char __user *buf, > size_t count, loff_t pos); > asmlinkage long sys_preadv(unsigned long fd, const struct iovec __user *vec, > unsigned long vlen, unsigned long pos_l, unsigned long pos_h); > +asmlinkage long sys_preadv2(unsigned long fd, const struct iovec __user *vec, > + unsigned long vlen, unsigned long pos_l, unsigned long pos_h, > + int flags); > asmlinkage long sys_pwritev(unsigned long fd, const struct iovec __user *vec, > unsigned long vlen, unsigned long pos_l, unsigned long pos_h); > +asmlinkage long sys_pwritev2(unsigned long fd, const struct iovec __user *vec, > + unsigned long vlen, unsigned long pos_l, unsigned long pos_h, > + int flags); > asmlinkage long sys_getcwd(char __user *buf, unsigned long size); > asmlinkage long sys_mkdir(const char __user *pathname, umode_t mode); > asmlinkage long sys_chdir(const char __user *filename); > diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h > index 22749c1..9406018 100644 > --- a/include/uapi/asm-generic/unistd.h > +++ b/include/uapi/asm-generic/unistd.h > @@ -213,6 +213,10 @@ __SC_COMP(__NR_pwrite64, sys_pwrite64, compat_sys_pwrite64) > __SC_COMP(__NR_preadv, sys_preadv, compat_sys_preadv) > #define __NR_pwritev 70 > __SC_COMP(__NR_pwritev, sys_pwritev, compat_sys_pwritev) > +#define __NR_preadv2 281 > +__SC_COMP(__NR_preadv2, sys_preadv2, compat_sys_preadv2) > +#define __NR_pwritev2 282 > +__SC_COMP(__NR_pwritev2, sys_pwritev2, compat_sys_pwritev2) > > /* fs/sendfile.c */ > #define __NR3264_sendfile 71 > @@ -709,7 +713,7 @@ __SYSCALL(__NR_memfd_create, sys_memfd_create) > __SYSCALL(__NR_bpf, sys_bpf) > > #undef __NR_syscalls > -#define __NR_syscalls 281 > +#define __NR_syscalls 283 > > /* > * All syscalls below here should go away really, > diff --git a/mm/filemap.c b/mm/filemap.c > index 14b4642..530c263 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -1457,6 +1457,7 @@ static void shrink_readahead_size_eio(struct file *filp, > * @ppos: current file position > * @iter: data destination > * @written: already copied > + * @flags: optional flags > * > * This is a generic file read routine, and uses the > * mapping->a_ops->readpage() function for the actual low-level stuff. > @@ -1465,7 +1466,7 @@ static void shrink_readahead_size_eio(struct file *filp, > * of the logic when it comes to error handling etc. > */ > static ssize_t do_generic_file_read(struct file *filp, loff_t *ppos, > - struct iov_iter *iter, ssize_t written) > + struct iov_iter *iter, ssize_t written, int flags) > { > struct address_space *mapping = filp->f_mapping; > struct inode *inode = mapping->host; > @@ -1735,7 +1736,7 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) > } > } > > - retval = do_generic_file_read(file, ppos, iter, retval); > + retval = do_generic_file_read(file, ppos, iter, retval, iocb->ki_rwflags); > out: > return retval; > } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/