summaryrefslogtreecommitdiff
path: root/lib
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 15:31:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-14 15:31:03 -0700
commitca2ec32658db160745990496f0f4580056a5dc9f (patch)
treed211f239219c85214da46dc1cbad4184a81d0248 /lib
parent6c8a53c9e6a151fffb07f8b4c34bd1e33dddd467 (diff)
parentfdc81f45e9f57858da6351836507fbcf1b7583ee (diff)
Merge branch 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs update from Al Viro: "Part one: - struct filename-related cleanups - saner iov_iter_init() replacements (and switching the syscalls to use of those) - ntfs switch to ->write_iter() (Anton) - aio cleanups and splitting iocb into common and async parts (Christoph) - assorted fixes (me, bfields, Andrew Elble) There's a lot more, including the completion of switchover to ->{read,write}_iter(), d_inode/d_backing_inode annotations, f_flags race fixes, etc, but that goes after #for-davem merge. David has pulled it, and once it's in I'll send the next vfs pull request" * 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (35 commits) sg_start_req(): use import_iovec() sg_start_req(): make sure that there's not too many elements in iovec blk_rq_map_user(): use import_single_range() sg_io(): use import_iovec() process_vm_access: switch to {compat_,}import_iovec() switch keyctl_instantiate_key_common() to iov_iter switch {compat_,}do_readv_writev() to {compat_,}import_iovec() aio_setup_vectored_rw(): switch to {compat_,}import_iovec() vmsplice_to_user(): switch to import_iovec() kill aio_setup_single_vector() aio: simplify arguments of aio_setup_..._rw() aio: lift iov_iter_init() into aio_setup_..._rw() lift iov_iter into {compat_,}do_readv_writev() NFS: fix BUG() crash in notify_change() with patch to chown_common() dcache: return -ESTALE not -EBUSY on distributed fs race NTFS: Version 2.1.32 - Update file write from aio_write to write_iter. VFS: Add iov_iter_fault_in_multipages_readable() drop bogus check in file_open_root() switch security_inode_getattr() to struct path * constify tomoyo_realpath_from_path() ...
Diffstat (limited to 'lib')
-rw-r--r--lib/iov_iter.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 9d96e283520c..75232ad0a5e7 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -317,6 +317,32 @@ int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
}
EXPORT_SYMBOL(iov_iter_fault_in_readable);
+/*
+ * Fault in one or more iovecs of the given iov_iter, to a maximum length of
+ * bytes. For each iovec, fault in each page that constitutes the iovec.
+ *
+ * Return 0 on success, or non-zero if the memory could not be accessed (i.e.
+ * because it is an invalid address).
+ */
+int iov_iter_fault_in_multipages_readable(struct iov_iter *i, size_t bytes)
+{
+ size_t skip = i->iov_offset;
+ const struct iovec *iov;
+ int err;
+ struct iovec v;
+
+ if (!(i->type & (ITER_BVEC|ITER_KVEC))) {
+ iterate_iovec(i, bytes, v, iov, skip, ({
+ err = fault_in_multipages_readable(v.iov_base,
+ v.iov_len);
+ if (unlikely(err))
+ return err;
+ 0;}))
+ }
+ return 0;
+}
+EXPORT_SYMBOL(iov_iter_fault_in_multipages_readable);
+
void iov_iter_init(struct iov_iter *i, int direction,
const struct iovec *iov, unsigned long nr_segs,
size_t count)
@@ -766,3 +792,60 @@ const void *dup_iter(struct iov_iter *new, struct iov_iter *old, gfp_t flags)
flags);
}
EXPORT_SYMBOL(dup_iter);
+
+int import_iovec(int type, const struct iovec __user * uvector,
+ unsigned nr_segs, unsigned fast_segs,
+ struct iovec **iov, struct iov_iter *i)
+{
+ ssize_t n;
+ struct iovec *p;
+ n = rw_copy_check_uvector(type, uvector, nr_segs, fast_segs,
+ *iov, &p);
+ if (n < 0) {
+ if (p != *iov)
+ kfree(p);
+ *iov = NULL;
+ return n;
+ }
+ iov_iter_init(i, type, p, nr_segs, n);
+ *iov = p == *iov ? NULL : p;
+ return 0;
+}
+EXPORT_SYMBOL(import_iovec);
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+
+int compat_import_iovec(int type, const struct compat_iovec __user * uvector,
+ unsigned nr_segs, unsigned fast_segs,
+ struct iovec **iov, struct iov_iter *i)
+{
+ ssize_t n;
+ struct iovec *p;
+ n = compat_rw_copy_check_uvector(type, uvector, nr_segs, fast_segs,
+ *iov, &p);
+ if (n < 0) {
+ if (p != *iov)
+ kfree(p);
+ *iov = NULL;
+ return n;
+ }
+ iov_iter_init(i, type, p, nr_segs, n);
+ *iov = p == *iov ? NULL : p;
+ return 0;
+}
+#endif
+
+int import_single_range(int rw, void __user *buf, size_t len,
+ struct iovec *iov, struct iov_iter *i)
+{
+ if (len > MAX_RW_COUNT)
+ len = MAX_RW_COUNT;
+ if (unlikely(!access_ok(!rw, buf, len)))
+ return -EFAULT;
+
+ iov->iov_base = buf;
+ iov->iov_len = len;
+ iov_iter_init(i, rw, iov, 1, len);
+ return 0;
+}