| Message ID | 20210706050541.1974618-1-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] iomap: remove the length variable in iomap_seek_data | expand |
On Tue, Jul 06, 2021 at 07:05:40AM +0200, Christoph Hellwig wrote: > The length variable is rather pointless given that it can be trivially > deduced from offset and size. Also the initial calculation can lead > to KASAN warnings. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > Reported-by: Leizhen (ThunderTown) <thunder.leizhen@huawei.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
On Tue, Jul 06, 2021 at 07:05:40AM +0200, Christoph Hellwig wrote: > The length variable is rather pointless given that it can be trivially > deduced from offset and size. Also the initial calculation can lead > to KASAN warnings. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > Reported-by: Leizhen (ThunderTown) <thunder.leizhen@huawei.com> Looks good! Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D > --- > fs/iomap/seek.c | 16 ++++++---------- > 1 file changed, 6 insertions(+), 10 deletions(-) > > diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c > index dab1b02eba5b7f..50b8f1418f2668 100644 > --- a/fs/iomap/seek.c > +++ b/fs/iomap/seek.c > @@ -83,27 +83,23 @@ loff_t > iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops) > { > loff_t size = i_size_read(inode); > - loff_t length = size - offset; > loff_t ret; > > /* Nothing to be found before or beyond the end of the file. */ > if (offset < 0 || offset >= size) > return -ENXIO; > > - while (length > 0) { > - ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops, - &offset, iomap_seek_data_actor); > + while (offset < size) { > + ret = iomap_apply(inode, offset, size - offset, IOMAP_REPORT, > + ops, &offset, iomap_seek_data_actor); > if (ret < 0) > return ret; > if (ret == 0) > - break; > - > + return offset; > offset += ret; > - length -= ret; > } > > - if (length <= 0) > - return -ENXIO; > - return offset; > + /* We've reached the end of the file without finding data */ > + return -ENXIO; > } > EXPORT_SYMBOL_GPL(iomap_seek_data); > -- > 2.30.2 >
diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c index dab1b02eba5b7f..50b8f1418f2668 100644 --- a/fs/iomap/seek.c +++ b/fs/iomap/seek.c @@ -83,27 +83,23 @@ loff_t iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops) { loff_t size = i_size_read(inode); - loff_t length = size - offset; loff_t ret; /* Nothing to be found before or beyond the end of the file. */ if (offset < 0 || offset >= size) return -ENXIO; - while (length > 0) { - ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops, - &offset, iomap_seek_data_actor); + while (offset < size) { + ret = iomap_apply(inode, offset, size - offset, IOMAP_REPORT, + ops, &offset, iomap_seek_data_actor); if (ret < 0) return ret; if (ret == 0) - break; - + return offset; offset += ret; - length -= ret; } - if (length <= 0) - return -ENXIO; - return offset; + /* We've reached the end of the file without finding data */ + return -ENXIO; } EXPORT_SYMBOL_GPL(iomap_seek_data);
The length variable is rather pointless given that it can be trivially deduced from offset and size. Also the initial calculation can lead to KASAN warnings. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Leizhen (ThunderTown) <thunder.leizhen@huawei.com> --- fs/iomap/seek.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-)