3.7-stable review patch. If anyone has any objections, please let me know.
------------------ From: Sebastian Andrzej Siewior <[email protected]> commit 40ff2c3b3da35dd3a00ac6722056a59b4b3f2caf upstream. This patch changes vectored file I/O to use kmap + kunmap when mapping incoming SGL memory -> struct iovec in order to properly support 32-bit highmem configurations. This is because an extra bounce buffer may be required when processing scatterlist pages allocated with GFP_KERNEL. Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/target/target_core_file.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/drivers/target/target_core_file.c +++ b/drivers/target/target_core_file.c @@ -260,7 +260,7 @@ static int fd_do_readv(struct se_cmd *cm for_each_sg(sgl, sg, sgl_nents, i) { iov[i].iov_len = sg->length; - iov[i].iov_base = sg_virt(sg); + iov[i].iov_base = kmap(sg_page(sg)) + sg->offset; } old_fs = get_fs(); @@ -268,6 +268,8 @@ static int fd_do_readv(struct se_cmd *cm ret = vfs_readv(fd, &iov[0], sgl_nents, &pos); set_fs(old_fs); + for_each_sg(sgl, sg, sgl_nents, i) + kunmap(sg_page(sg)); kfree(iov); /* * Return zeros and GOOD status even if the READ did not return @@ -313,7 +315,7 @@ static int fd_do_writev(struct se_cmd *c for_each_sg(sgl, sg, sgl_nents, i) { iov[i].iov_len = sg->length; - iov[i].iov_base = sg_virt(sg); + iov[i].iov_base = kmap(sg_page(sg)) + sg->offset; } old_fs = get_fs(); @@ -321,6 +323,9 @@ static int fd_do_writev(struct se_cmd *c ret = vfs_writev(fd, &iov[0], sgl_nents, &pos); set_fs(old_fs); + for_each_sg(sgl, sg, sgl_nents, i) + kunmap(sg_page(sg)); + kfree(iov); if (ret < 0 || ret != cmd->data_length) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
