From ac15ac0669d5f5ce7fddec0d9cf3721c42d77a2c Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 20 Mar 2015 20:10:21 -0400 Subject: [PATCH] lift iov_iter into {compat_,}do_readv_writev() get it closer to matching {compat_,}rw_copy_check_uvector(). Signed-off-by: Al Viro --- fs/read_write.c | 54 +++++++++++++++++++++---------------------------- 1 file changed, 23 insertions(+), 31 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 99a6ef946d01..11980f164432 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -695,25 +695,23 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) } EXPORT_SYMBOL(iov_shorten); -static ssize_t do_iter_readv_writev(struct file *filp, int rw, const struct iovec *iov, - unsigned long nr_segs, size_t len, loff_t *ppos, iter_fn_t fn) +static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, + loff_t *ppos, iter_fn_t fn) { struct kiocb kiocb; - struct iov_iter iter; ssize_t ret; init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; - iov_iter_init(&iter, rw, iov, nr_segs, len); - ret = fn(&kiocb, &iter); + ret = fn(&kiocb, iter); BUG_ON(ret == -EIOCBQUEUED); *ppos = kiocb.ki_pos; return ret; } -static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, - unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) +static ssize_t do_sync_readv_writev(struct file *filp, struct iov_iter *iter, + loff_t *ppos, iov_fn_t fn) { struct kiocb kiocb; ssize_t ret; @@ -721,30 +719,23 @@ static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; - ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); + ret = fn(&kiocb, iter->iov, iter->nr_segs, kiocb.ki_pos); BUG_ON(ret == -EIOCBQUEUED); *ppos = kiocb.ki_pos; return ret; } /* Do it by hand, with file-ops */ -static ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, - unsigned long nr_segs, loff_t *ppos, io_fn_t fn) +static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, + loff_t *ppos, io_fn_t fn) { - struct iovec *vector = iov; ssize_t ret = 0; - while (nr_segs > 0) { - void __user *base; - size_t len; + while (iov_iter_count(iter)) { + struct iovec iovec = iov_iter_iovec(iter); ssize_t nr; - base = vector->iov_base; - len = vector->iov_len; - vector++; - nr_segs--; - - nr = fn(filp, base, len, ppos); + nr = fn(filp, iovec.iov_base, iovec.iov_len, ppos); if (nr < 0) { if (!ret) @@ -752,8 +743,9 @@ static ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, break; } ret += nr; - if (nr != len) + if (nr != iovec.iov_len) break; + iov_iter_advance(iter, nr); } return ret; @@ -844,6 +836,7 @@ static ssize_t do_readv_writev(int type, struct file *file, size_t tot_len; struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; + struct iov_iter iter; ssize_t ret; io_fn_t fn; iov_fn_t fnv; @@ -853,6 +846,7 @@ static ssize_t do_readv_writev(int type, struct file *file, ARRAY_SIZE(iovstack), iovstack, &iov); if (ret <= 0) goto out; + iov_iter_init(&iter, type, iov, nr_segs, ret); tot_len = ret; ret = rw_verify_area(type, file, pos, tot_len); @@ -872,13 +866,11 @@ static ssize_t 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); + ret = do_iter_readv_writev(file, &iter, pos, iter_fn); else if (fnv) - ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, - pos, fnv); + ret = do_sync_readv_writev(file, &iter, pos, fnv); else - ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); + ret = do_loop_readv_writev(file, &iter, pos, fn); if (type != READ) file_end_write(file); @@ -1024,6 +1016,7 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, compat_ssize_t tot_len; struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; + struct iov_iter iter; ssize_t ret; io_fn_t fn; iov_fn_t fnv; @@ -1033,6 +1026,7 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, UIO_FASTIOV, iovstack, &iov); if (ret <= 0) goto out; + iov_iter_init(&iter, type, iov, nr_segs, ret); tot_len = ret; ret = rw_verify_area(type, file, pos, tot_len); @@ -1052,13 +1046,11 @@ 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); + ret = do_iter_readv_writev(file, &iter, pos, iter_fn); else if (fnv) - ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, - pos, fnv); + ret = do_sync_readv_writev(file, &iter, pos, fnv); else - ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); + ret = do_loop_readv_writev(file, &iter, pos, fn); if (type != READ) file_end_write(file); -- 2.30.2