* [PATCH v4 1/5] fs: split off do_user_path_at_empty from user_path_at_empty()
2021-12-15 22:16 [PATCH v4 0/5] io_uring: add xattr support Stefan Roesch
@ 2021-12-15 22:16 ` Stefan Roesch
2021-12-15 22:16 ` [PATCH v4 2/5] fs: split off setxattr_setup function from setxattr Stefan Roesch
` (3 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Stefan Roesch @ 2021-12-15 22:16 UTC (permalink / raw)
To: io-uring, linux-fsdevel, kernel-team; +Cc: viro, shr
This splits off a do_user_path_at_empty function from the
user_path_at_empty_function. This is required so it can be
called from io_uring.
Signed-off-by: Stefan Roesch <[email protected]>
---
fs/namei.c | 10 ++++++++--
include/linux/namei.h | 2 ++
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index 1f9d2187c765..d988e241b32c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2794,12 +2794,18 @@ int path_pts(struct path *path)
}
#endif
+int do_user_path_at_empty(int dfd, struct filename *filename, unsigned int flags,
+ struct path *path)
+{
+ return filename_lookup(dfd, filename, flags, path, NULL);
+}
+
int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
- struct path *path, int *empty)
+ struct path *path, int *empty)
{
struct filename *filename = getname_flags(name, flags, empty);
- int ret = filename_lookup(dfd, filename, flags, path, NULL);
+ int ret = do_user_path_at_empty(dfd, filename, flags, path);
putname(filename);
return ret;
}
diff --git a/include/linux/namei.h b/include/linux/namei.h
index e89329bb3134..8f3ef38c057b 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -49,6 +49,8 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT};
extern int path_pts(struct path *path);
+extern int do_user_path_at_empty(int dfd, struct filename *filename,
+ unsigned int flags, struct path *path);
extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);
static inline int user_path_at(int dfd, const char __user *name, unsigned flags,
--
2.30.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v4 2/5] fs: split off setxattr_setup function from setxattr
2021-12-15 22:16 [PATCH v4 0/5] io_uring: add xattr support Stefan Roesch
2021-12-15 22:16 ` [PATCH v4 1/5] fs: split off do_user_path_at_empty from user_path_at_empty() Stefan Roesch
@ 2021-12-15 22:16 ` Stefan Roesch
2021-12-15 22:17 ` [PATCH v4 3/5] fs: split off do_getxattr from getxattr Stefan Roesch
` (2 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Stefan Roesch @ 2021-12-15 22:16 UTC (permalink / raw)
To: io-uring, linux-fsdevel, kernel-team; +Cc: viro, shr
This splits of the setup part of the function
setxattr in its own dedicated function called
setxattr_setup.
This makes it possible to call this function
from io_uring in the pre-processing of an
xattr request.
Signed-off-by: Stefan Roesch <[email protected]>
---
fs/internal.h | 17 ++++++++++++
fs/xattr.c | 75 ++++++++++++++++++++++++++++++++++-----------------
2 files changed, 67 insertions(+), 25 deletions(-)
diff --git a/fs/internal.h b/fs/internal.h
index 7979ff8d168c..1b88f29905e6 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -194,3 +194,20 @@ long splice_file_to_pipe(struct file *in,
struct pipe_inode_info *opipe,
loff_t *offset,
size_t len, unsigned int flags);
+
+ /*
+ * fs/xattr.c:
+ */
+struct xattr_ctx {
+ /* Value of attribute */
+ const void __user *value;
+ size_t size;
+ /* Attribute name */
+ char *kname;
+ int kname_sz;
+ int flags;
+};
+
+void *setxattr_setup(struct user_namespace *mnt_userns,
+ const char __user *name,
+ struct xattr_ctx *data);
diff --git a/fs/xattr.c b/fs/xattr.c
index 5c8c5175b385..79afea64d7ba 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -25,6 +25,8 @@
#include <linux/uaccess.h>
+#include "internal.h"
+
static const char *
strcmp_prefix(const char *a, const char *a_prefix)
{
@@ -539,43 +541,66 @@ EXPORT_SYMBOL_GPL(vfs_removexattr);
/*
* Extended attribute SET operations
*/
-static long
-setxattr(struct user_namespace *mnt_userns, struct dentry *d,
- const char __user *name, const void __user *value, size_t size,
- int flags)
+
+void *setxattr_setup(struct user_namespace *mnt_userns, const char __user *name,
+ struct xattr_ctx *ctx)
{
- int error;
void *kvalue = NULL;
- char kname[XATTR_NAME_MAX + 1];
+ int error;
- if (flags & ~(XATTR_CREATE|XATTR_REPLACE))
- return -EINVAL;
+ if (ctx->flags & ~(XATTR_CREATE|XATTR_REPLACE))
+ return ERR_PTR(-EINVAL);
- error = strncpy_from_user(kname, name, sizeof(kname));
- if (error == 0 || error == sizeof(kname))
- error = -ERANGE;
+ error = strncpy_from_user(ctx->kname, name, ctx->kname_sz);
+ if (error == 0 || error == ctx->kname_sz)
+ return ERR_PTR(-ERANGE);
if (error < 0)
- return error;
+ return ERR_PTR(error);
- if (size) {
- if (size > XATTR_SIZE_MAX)
- return -E2BIG;
- kvalue = kvmalloc(size, GFP_KERNEL);
+ if (ctx->size) {
+ if (ctx->size > XATTR_SIZE_MAX)
+ return ERR_PTR(-E2BIG);
+
+ kvalue = kvmalloc(ctx->size, GFP_KERNEL);
if (!kvalue)
- return -ENOMEM;
- if (copy_from_user(kvalue, value, size)) {
- error = -EFAULT;
- goto out;
+ return ERR_PTR(-ENOMEM);
+
+ if (copy_from_user(kvalue, ctx->value, ctx->size)) {
+ kvfree(kvalue);
+ return ERR_PTR(-EFAULT);
}
- if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
- (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
- posix_acl_fix_xattr_from_user(mnt_userns, kvalue, size);
+
+ if ((strcmp(ctx->kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
+ (strcmp(ctx->kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
+ posix_acl_fix_xattr_from_user(mnt_userns, kvalue, ctx->size);
}
+ return kvalue;
+}
+
+static long
+setxattr(struct user_namespace *mnt_userns, struct dentry *d,
+ const char __user *name, const void __user *value, size_t size,
+ int flags)
+{
+ char kname[XATTR_NAME_MAX + 1];
+ struct xattr_ctx ctx = {
+ .value = value,
+ .size = size,
+ .kname = kname,
+ .kname_sz = sizeof(kname),
+ .flags = flags,
+ };
+ void *kvalue;
+ int error;
+
+ kvalue = setxattr_setup(mnt_userns, name, &ctx);
+ if (IS_ERR(kvalue))
+ return PTR_ERR(kvalue);
+
error = vfs_setxattr(mnt_userns, d, kname, kvalue, size, flags);
-out:
- kvfree(kvalue);
+ kvfree(kvalue);
return error;
}
--
2.30.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v4 3/5] fs: split off do_getxattr from getxattr
2021-12-15 22:16 [PATCH v4 0/5] io_uring: add xattr support Stefan Roesch
2021-12-15 22:16 ` [PATCH v4 1/5] fs: split off do_user_path_at_empty from user_path_at_empty() Stefan Roesch
2021-12-15 22:16 ` [PATCH v4 2/5] fs: split off setxattr_setup function from setxattr Stefan Roesch
@ 2021-12-15 22:17 ` Stefan Roesch
2021-12-15 22:17 ` [PATCH v4 4/5] io_uring: add fsetxattr and setxattr support Stefan Roesch
2021-12-15 22:17 ` [PATCH v4 5/5] io_uring: add fgetxattr and getxattr support Stefan Roesch
4 siblings, 0 replies; 8+ messages in thread
From: Stefan Roesch @ 2021-12-15 22:17 UTC (permalink / raw)
To: io-uring, linux-fsdevel, kernel-team; +Cc: viro, shr
This splits off do_getxattr function from the getxattr
function. This will allow io_uring to call it from its
io worker.
Signed-off-by: Stefan Roesch <[email protected]>
---
fs/internal.h | 6 ++++++
fs/xattr.c | 31 ++++++++++++++++++++-----------
2 files changed, 26 insertions(+), 11 deletions(-)
diff --git a/fs/internal.h b/fs/internal.h
index 1b88f29905e6..5edaee02b50d 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -208,6 +208,12 @@ struct xattr_ctx {
int flags;
};
+ssize_t do_getxattr(struct user_namespace *mnt_userns,
+ struct dentry *d,
+ const char *kname,
+ void __user *value,
+ size_t size);
+
void *setxattr_setup(struct user_namespace *mnt_userns,
const char __user *name,
struct xattr_ctx *data);
diff --git a/fs/xattr.c b/fs/xattr.c
index 79afea64d7ba..c333fcdac241 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -666,19 +666,12 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
/*
* Extended attribute GET operations
*/
-static ssize_t
-getxattr(struct user_namespace *mnt_userns, struct dentry *d,
- const char __user *name, void __user *value, size_t size)
+ssize_t
+do_getxattr(struct user_namespace *mnt_userns, struct dentry *d,
+ const char *kname, void __user *value, size_t size)
{
- ssize_t error;
void *kvalue = NULL;
- char kname[XATTR_NAME_MAX + 1];
-
- error = strncpy_from_user(kname, name, sizeof(kname));
- if (error == 0 || error == sizeof(kname))
- error = -ERANGE;
- if (error < 0)
- return error;
+ ssize_t error;
if (size) {
if (size > XATTR_SIZE_MAX)
@@ -706,6 +699,22 @@ getxattr(struct user_namespace *mnt_userns, struct dentry *d,
return error;
}
+static ssize_t
+getxattr(struct user_namespace *mnt_userns, struct dentry *d,
+ const char __user *name, void __user *value, size_t size)
+{
+ ssize_t error;
+ char kname[XATTR_NAME_MAX + 1];
+
+ error = strncpy_from_user(kname, name, sizeof(kname));
+ if (error == 0 || error == sizeof(kname))
+ error = -ERANGE;
+ if (error < 0)
+ return error;
+
+ return do_getxattr(mnt_userns, d, kname, value, size);
+}
+
static ssize_t path_getxattr(const char __user *pathname,
const char __user *name, void __user *value,
size_t size, unsigned int lookup_flags)
--
2.30.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v4 4/5] io_uring: add fsetxattr and setxattr support
2021-12-15 22:16 [PATCH v4 0/5] io_uring: add xattr support Stefan Roesch
` (2 preceding siblings ...)
2021-12-15 22:17 ` [PATCH v4 3/5] fs: split off do_getxattr from getxattr Stefan Roesch
@ 2021-12-15 22:17 ` Stefan Roesch
2021-12-21 17:27 ` Pavel Begunkov
2021-12-15 22:17 ` [PATCH v4 5/5] io_uring: add fgetxattr and getxattr support Stefan Roesch
4 siblings, 1 reply; 8+ messages in thread
From: Stefan Roesch @ 2021-12-15 22:17 UTC (permalink / raw)
To: io-uring, linux-fsdevel, kernel-team; +Cc: viro, shr
This adds support to io_uring for the fsetxattr and setxattr API.
Signed-off-by: Stefan Roesch <[email protected]>
---
fs/io_uring.c | 171 ++++++++++++++++++++++++++++++++++
include/uapi/linux/io_uring.h | 6 +-
2 files changed, 176 insertions(+), 1 deletion(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 5092dfe56da6..fc2239635342 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -82,6 +82,7 @@
#include <linux/audit.h>
#include <linux/security.h>
#include <linux/atomic-ref.h>
+#include <linux/xattr.h>
#define CREATE_TRACE_POINTS
#include <trace/events/io_uring.h>
@@ -719,6 +720,13 @@ struct io_async_rw {
struct wait_page_queue wpq;
};
+struct io_xattr {
+ struct file *file;
+ struct xattr_ctx ctx;
+ void *value;
+ struct filename *filename;
+};
+
enum {
REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
@@ -858,6 +866,7 @@ struct io_kiocb {
struct io_mkdir mkdir;
struct io_symlink symlink;
struct io_hardlink hardlink;
+ struct io_xattr xattr;
};
u8 opcode;
@@ -1107,6 +1116,10 @@ static const struct io_op_def io_op_defs[] = {
[IORING_OP_MKDIRAT] = {},
[IORING_OP_SYMLINKAT] = {},
[IORING_OP_LINKAT] = {},
+ [IORING_OP_FSETXATTR] = {
+ .needs_file = 1
+ },
+ [IORING_OP_SETXATTR] = {},
};
/* requests with any of those set should undergo io_disarm_next() */
@@ -3876,6 +3889,144 @@ static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
return 0;
}
+static int __io_setxattr_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe,
+ struct user_namespace *user_ns)
+{
+ struct io_xattr *ix = &req->xattr;
+ const char __user *name;
+ void *ret;
+
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+ if (unlikely(sqe->ioprio))
+ return -EINVAL;
+ if (unlikely(req->flags & REQ_F_FIXED_FILE))
+ return -EBADF;
+
+ ix->filename = NULL;
+ name = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ ix->ctx.value = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+ ix->ctx.size = READ_ONCE(sqe->len);
+ ix->ctx.flags = READ_ONCE(sqe->xattr_flags);
+
+ ix->ctx.kname = kmalloc(XATTR_NAME_MAX + 1, GFP_KERNEL);
+ if (!ix->ctx.kname)
+ return -ENOMEM;
+ ix->ctx.kname_sz = XATTR_NAME_MAX + 1;
+
+ ret = setxattr_setup(user_ns, name, &ix->ctx);
+ if (IS_ERR(ret)) {
+ kfree(ix->ctx.kname);
+ return PTR_ERR(ret);
+ }
+
+ ix->value = ret;
+ req->flags |= REQ_F_NEED_CLEANUP;
+ return 0;
+}
+
+static int io_setxattr_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ struct io_xattr *ix = &req->xattr;
+ const char __user *path;
+ int ret;
+
+ ret = __io_setxattr_prep(req, sqe, current_user_ns());
+ if (ret)
+ return ret;
+
+ path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
+
+ ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
+ if (IS_ERR(ix->filename)) {
+ ret = PTR_ERR(ix->filename);
+ ix->filename = NULL;
+ }
+
+ return ret;
+}
+
+static int io_fsetxattr_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ return __io_setxattr_prep(req, sqe, file_mnt_user_ns(req->file));
+}
+
+static int __io_setxattr(struct io_kiocb *req, unsigned int issue_flags,
+ struct path *path)
+{
+ struct io_xattr *ix = &req->xattr;
+ int ret;
+
+ ret = mnt_want_write(path->mnt);
+ if (!ret) {
+ ret = vfs_setxattr(mnt_user_ns(path->mnt), path->dentry,
+ ix->ctx.kname, ix->value, ix->ctx.size,
+ ix->ctx.flags);
+ mnt_drop_write(path->mnt);
+ }
+
+ return ret;
+}
+
+static int io_fsetxattr(struct io_kiocb *req, unsigned int issue_flags)
+{
+ struct io_xattr *ix = &req->xattr;
+ int ret;
+
+ if (issue_flags & IO_URING_F_NONBLOCK)
+ return -EAGAIN;
+
+ ret = __io_setxattr(req, issue_flags, &req->file->f_path);
+
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ kfree(ix->ctx.kname);
+
+ if (ix->value)
+ kvfree(ix->value);
+ if (ret < 0)
+ req_set_fail(req);
+
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int io_setxattr(struct io_kiocb *req, unsigned int issue_flags)
+{
+ struct io_xattr *ix = &req->xattr;
+ unsigned int lookup_flags = LOOKUP_FOLLOW;
+ struct path path;
+ int ret;
+
+ if (issue_flags & IO_URING_F_NONBLOCK)
+ return -EAGAIN;
+
+retry:
+ ret = do_user_path_at_empty(AT_FDCWD, ix->filename, lookup_flags, &path);
+ putname(ix->filename);
+ if (!ret) {
+ ret = __io_setxattr(req, issue_flags, &path);
+ path_put(&path);
+ if (retry_estale(ret, lookup_flags)) {
+ lookup_flags |= LOOKUP_REVAL;
+ goto retry;
+ }
+ }
+
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ kfree(ix->ctx.kname);
+
+ if (ix->value)
+ kvfree(ix->value);
+ if (ret < 0)
+ req_set_fail(req);
+
+ io_req_complete(req, ret);
+ return 0;
+}
+
static int io_unlinkat_prep(struct io_kiocb *req,
const struct io_uring_sqe *sqe)
{
@@ -6574,6 +6725,10 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
return io_symlinkat_prep(req, sqe);
case IORING_OP_LINKAT:
return io_linkat_prep(req, sqe);
+ case IORING_OP_FSETXATTR:
+ return io_fsetxattr_prep(req, sqe);
+ case IORING_OP_SETXATTR:
+ return io_setxattr_prep(req, sqe);
}
printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
@@ -6715,6 +6870,15 @@ static void io_clean_op(struct io_kiocb *req)
putname(req->hardlink.oldpath);
putname(req->hardlink.newpath);
break;
+ case IORING_OP_SETXATTR:
+ if (req->xattr.filename)
+ putname(req->xattr.filename);
+ fallthrough;
+ case IORING_OP_FSETXATTR:
+ kfree(req->xattr.ctx.kname);
+ if (req->xattr.value)
+ kvfree(req->xattr.value);
+ break;
}
}
if ((req->flags & REQ_F_POLLED) && req->apoll) {
@@ -6857,6 +7021,12 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
case IORING_OP_LINKAT:
ret = io_linkat(req, issue_flags);
break;
+ case IORING_OP_FSETXATTR:
+ ret = io_fsetxattr(req, issue_flags);
+ break;
+ case IORING_OP_SETXATTR:
+ ret = io_setxattr(req, issue_flags);
+ break;
default:
ret = -EINVAL;
break;
@@ -11225,6 +11395,7 @@ static int __init io_uring_init(void)
BUILD_BUG_SQE_ELEM(42, __u16, personality);
BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
BUILD_BUG_SQE_ELEM(44, __u32, file_index);
+ BUILD_BUG_SQE_ELEM(48, __u64, addr3);
BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
sizeof(struct io_uring_rsrc_update));
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 787f491f0d2a..dbf473900da2 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -45,6 +45,7 @@ struct io_uring_sqe {
__u32 rename_flags;
__u32 unlink_flags;
__u32 hardlink_flags;
+ __u32 xattr_flags;
};
__u64 user_data; /* data to be passed back at completion time */
/* pack this to avoid bogus arm OABI complaints */
@@ -60,7 +61,8 @@ struct io_uring_sqe {
__s32 splice_fd_in;
__u32 file_index;
};
- __u64 __pad2[2];
+ __u64 addr3;
+ __u64 __pad2[1];
};
enum {
@@ -143,6 +145,8 @@ enum {
IORING_OP_MKDIRAT,
IORING_OP_SYMLINKAT,
IORING_OP_LINKAT,
+ IORING_OP_FSETXATTR,
+ IORING_OP_SETXATTR,
/* this goes last, obviously */
IORING_OP_LAST,
--
2.30.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v4 4/5] io_uring: add fsetxattr and setxattr support
2021-12-15 22:17 ` [PATCH v4 4/5] io_uring: add fsetxattr and setxattr support Stefan Roesch
@ 2021-12-21 17:27 ` Pavel Begunkov
0 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2021-12-21 17:27 UTC (permalink / raw)
To: Stefan Roesch, io-uring, linux-fsdevel, kernel-team; +Cc: viro
On 12/15/21 22:17, Stefan Roesch wrote:
> This adds support to io_uring for the fsetxattr and setxattr API.
Apart from potentially putname comment,
Reviewed-by: Pavel Begunkov <[email protected]>
>
> Signed-off-by: Stefan Roesch <[email protected]>
> ---
> fs/io_uring.c | 171 ++++++++++++++++++++++++++++++++++
> include/uapi/linux/io_uring.h | 6 +-
> 2 files changed, 176 insertions(+), 1 deletion(-)
>
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index 5092dfe56da6..fc2239635342 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
[...]> +static int __io_setxattr_prep(struct io_kiocb *req,
> + const struct io_uring_sqe *sqe,
> + struct user_namespace *user_ns)
> +{
> + struct io_xattr *ix = &req->xattr;
> + const char __user *name;
> + void *ret;
> +
> + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
> + return -EINVAL;
> + if (unlikely(sqe->ioprio))
> + return -EINVAL;
> + if (unlikely(req->flags & REQ_F_FIXED_FILE))
> + return -EBADF;
> +
> + ix->filename = NULL;
> + name = u64_to_user_ptr(READ_ONCE(sqe->addr));
> + ix->ctx.value = u64_to_user_ptr(READ_ONCE(sqe->addr2));
> + ix->ctx.size = READ_ONCE(sqe->len);
> + ix->ctx.flags = READ_ONCE(sqe->xattr_flags);
> +
> + ix->ctx.kname = kmalloc(XATTR_NAME_MAX + 1, GFP_KERNEL);
> + if (!ix->ctx.kname)
> + return -ENOMEM;> + ix->ctx.kname_sz = XATTR_NAME_MAX + 1;
Might make sense to let the userspace specify kname size, but
depends what is the average name length and how much of free
space we have in io_xattr
[...]
> +static int io_setxattr(struct io_kiocb *req, unsigned int issue_flags)
> +{
> + struct io_xattr *ix = &req->xattr;
> + unsigned int lookup_flags = LOOKUP_FOLLOW;
> + struct path path;
> + int ret;
> +
> + if (issue_flags & IO_URING_F_NONBLOCK)
> + return -EAGAIN;
> +
> +retry:
> + ret = do_user_path_at_empty(AT_FDCWD, ix->filename, lookup_flags, &path);
> + putname(ix->filename);
It putname() multiple times on retry, how does it work?
> + if (!ret) {
> + ret = __io_setxattr(req, issue_flags, &path);
> + path_put(&path);
> + if (retry_estale(ret, lookup_flags)) {
> + lookup_flags |= LOOKUP_REVAL;
> + goto retry;
> + }
> + }
> +
> + req->flags &= ~REQ_F_NEED_CLEANUP;
> + kfree(ix->ctx.kname);
> +
> + if (ix->value)
> + kvfree(ix->value);
> + if (ret < 0)
> + req_set_fail(req);
> +
> + io_req_complete(req, ret);
> + return 0;
> +}
> +
[...]
>
> printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
> @@ -6715,6 +6870,15 @@ static void io_clean_op(struct io_kiocb *req)
> putname(req->hardlink.oldpath);
> putname(req->hardlink.newpath);
> break;
> + case IORING_OP_SETXATTR:
> + if (req->xattr.filename)
> + putname(req->xattr.filename);
> + fallthrough;
> + case IORING_OP_FSETXATTR:
> + kfree(req->xattr.ctx.kname);
> + if (req->xattr.value)
> + kvfree(req->xattr.value);
nit: it's slow path and kvfree() handles NULLs, so we don't
really need NULL checks here.
--
Pavel Begunkov
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v4 5/5] io_uring: add fgetxattr and getxattr support
2021-12-15 22:16 [PATCH v4 0/5] io_uring: add xattr support Stefan Roesch
` (3 preceding siblings ...)
2021-12-15 22:17 ` [PATCH v4 4/5] io_uring: add fsetxattr and setxattr support Stefan Roesch
@ 2021-12-15 22:17 ` Stefan Roesch
2021-12-21 17:32 ` Pavel Begunkov
4 siblings, 1 reply; 8+ messages in thread
From: Stefan Roesch @ 2021-12-15 22:17 UTC (permalink / raw)
To: io-uring, linux-fsdevel, kernel-team; +Cc: viro, shr
This adds support to io_uring for the fgetxattr and getxattr API.
Signed-off-by: Stefan Roesch <[email protected]>
---
fs/io_uring.c | 150 ++++++++++++++++++++++++++++++++++
include/uapi/linux/io_uring.h | 2 +
2 files changed, 152 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index fc2239635342..c365944a8054 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1116,6 +1116,10 @@ static const struct io_op_def io_op_defs[] = {
[IORING_OP_MKDIRAT] = {},
[IORING_OP_SYMLINKAT] = {},
[IORING_OP_LINKAT] = {},
+ [IORING_OP_FGETXATTR] = {
+ .needs_file = 1
+ },
+ [IORING_OP_GETXATTR] = {},
[IORING_OP_FSETXATTR] = {
.needs_file = 1
},
@@ -3889,6 +3893,133 @@ static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
return 0;
}
+static int __io_getxattr_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ struct io_xattr *ix = &req->xattr;
+ const char __user *name;
+ int ret;
+
+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+ return -EINVAL;
+ if (unlikely(sqe->ioprio))
+ return -EINVAL;
+ if (unlikely(req->flags & REQ_F_FIXED_FILE))
+ return -EBADF;
+
+ ix->filename = NULL;
+ ix->value = NULL;
+ name = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ ix->ctx.value = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+ ix->ctx.size = READ_ONCE(sqe->len);
+ ix->ctx.flags = READ_ONCE(sqe->xattr_flags);
+
+ if (ix->ctx.flags)
+ return -EINVAL;
+
+ ix->ctx.kname = kmalloc(XATTR_NAME_MAX + 1, GFP_KERNEL);
+ if (!ix->ctx.kname)
+ return -ENOMEM;
+
+ ret = strncpy_from_user(ix->ctx.kname, name, XATTR_NAME_MAX + 1);
+ if (!ret || ret == XATTR_NAME_MAX + 1)
+ ret = -ERANGE;
+ if (ret < 0) {
+ kfree(ix->ctx.kname);
+ return ret;
+ }
+
+ req->flags |= REQ_F_NEED_CLEANUP;
+ return 0;
+}
+
+static int io_fgetxattr_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ return __io_getxattr_prep(req, sqe);
+}
+
+static int io_getxattr_prep(struct io_kiocb *req,
+ const struct io_uring_sqe *sqe)
+{
+ struct io_xattr *ix = &req->xattr;
+ const char __user *path;
+ int ret;
+
+ ret = __io_getxattr_prep(req, sqe);
+ if (ret)
+ return ret;
+
+ path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
+
+ ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
+ if (IS_ERR(ix->filename)) {
+ ret = PTR_ERR(ix->filename);
+ ix->filename = NULL;
+ }
+
+ return ret;
+}
+
+static int io_fgetxattr(struct io_kiocb *req, unsigned int issue_flags)
+{
+ struct io_xattr *ix = &req->xattr;
+ int ret;
+
+ if (issue_flags & IO_URING_F_NONBLOCK)
+ return -EAGAIN;
+
+ ret = do_getxattr(mnt_user_ns(req->file->f_path.mnt),
+ req->file->f_path.dentry,
+ ix->ctx.kname,
+ (void __user *)ix->ctx.value,
+ ix->ctx.size);
+
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ kfree(ix->ctx.kname);
+ if (ret < 0)
+ req_set_fail(req);
+
+ io_req_complete(req, ret);
+ return 0;
+}
+
+static int io_getxattr(struct io_kiocb *req, unsigned int issue_flags)
+{
+ struct io_xattr *ix = &req->xattr;
+ unsigned int lookup_flags = LOOKUP_FOLLOW;
+ struct path path;
+ int ret;
+
+ if (issue_flags & IO_URING_F_NONBLOCK)
+ return -EAGAIN;
+
+retry:
+ ret = do_user_path_at_empty(AT_FDCWD, ix->filename, lookup_flags, &path);
+ putname(ix->filename);
+ if (!ret) {
+ ret = do_getxattr(mnt_user_ns(path.mnt),
+ path.dentry,
+ ix->ctx.kname,
+ (void __user *)ix->ctx.value,
+ ix->ctx.size);
+
+ path_put(&path);
+ if (retry_estale(ret, lookup_flags)) {
+ lookup_flags |= LOOKUP_REVAL;
+ goto retry;
+ }
+ }
+
+ req->flags &= ~REQ_F_NEED_CLEANUP;
+ kfree(ix->ctx.kname);
+ if (ret < 0)
+ req_set_fail(req);
+
+ io_req_complete(req, ret);
+ return 0;
+}
+
static int __io_setxattr_prep(struct io_kiocb *req,
const struct io_uring_sqe *sqe,
struct user_namespace *user_ns)
@@ -6725,6 +6856,10 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
return io_symlinkat_prep(req, sqe);
case IORING_OP_LINKAT:
return io_linkat_prep(req, sqe);
+ case IORING_OP_FGETXATTR:
+ return io_fgetxattr_prep(req, sqe);
+ case IORING_OP_GETXATTR:
+ return io_getxattr_prep(req, sqe);
case IORING_OP_FSETXATTR:
return io_fsetxattr_prep(req, sqe);
case IORING_OP_SETXATTR:
@@ -6870,6 +7005,15 @@ static void io_clean_op(struct io_kiocb *req)
putname(req->hardlink.oldpath);
putname(req->hardlink.newpath);
break;
+
+ case IORING_OP_GETXATTR:
+ if (req->xattr.filename)
+ putname(req->xattr.filename);
+ fallthrough;
+ case IORING_OP_FGETXATTR:
+ kfree(req->xattr.ctx.kname);
+ break;
+
case IORING_OP_SETXATTR:
if (req->xattr.filename)
putname(req->xattr.filename);
@@ -7021,6 +7165,12 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
case IORING_OP_LINKAT:
ret = io_linkat(req, issue_flags);
break;
+ case IORING_OP_FGETXATTR:
+ ret = io_fgetxattr(req, issue_flags);
+ break;
+ case IORING_OP_GETXATTR:
+ ret = io_getxattr(req, issue_flags);
+ break;
case IORING_OP_FSETXATTR:
ret = io_fsetxattr(req, issue_flags);
break;
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index dbf473900da2..cd9160272308 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -145,7 +145,9 @@ enum {
IORING_OP_MKDIRAT,
IORING_OP_SYMLINKAT,
IORING_OP_LINKAT,
+ IORING_OP_FGETXATTR,
IORING_OP_FSETXATTR,
+ IORING_OP_GETXATTR,
IORING_OP_SETXATTR,
/* this goes last, obviously */
--
2.30.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v4 5/5] io_uring: add fgetxattr and getxattr support
2021-12-15 22:17 ` [PATCH v4 5/5] io_uring: add fgetxattr and getxattr support Stefan Roesch
@ 2021-12-21 17:32 ` Pavel Begunkov
0 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2021-12-21 17:32 UTC (permalink / raw)
To: Stefan Roesch, io-uring, linux-fsdevel, kernel-team; +Cc: viro
On 12/15/21 22:17, Stefan Roesch wrote:
> This adds support to io_uring for the fgetxattr and getxattr API.
Same comments as with 4/5, only one additional below
>
> Signed-off-by: Stefan Roesch <[email protected]>
> ---
> fs/io_uring.c | 150 ++++++++++++++++++++++++++++++++++
> include/uapi/linux/io_uring.h | 2 +
> 2 files changed, 152 insertions(+)
>
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index fc2239635342..c365944a8054 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
[...]
> diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
> index dbf473900da2..cd9160272308 100644
> --- a/include/uapi/linux/io_uring.h
> +++ b/include/uapi/linux/io_uring.h
> @@ -145,7 +145,9 @@ enum {
> IORING_OP_MKDIRAT,
> IORING_OP_SYMLINKAT,
> IORING_OP_LINKAT,
> + IORING_OP_FGETXATTR,
Even though it's just one-commit gap, it's not great changing uapi,
e.g. +1 to previous IORING_OP_FSETXATTR. It may actually make more
sense to keep xget and xfget closer together because you're reusing
code for them and compiler may _potentially_ better optimise it,
e.g. ifs in switches.
> IORING_OP_FSETXATTR,
> + IORING_OP_GETXATTR,
> IORING_OP_SETXATTR,
>
> /* this goes last, obviously */
--
Pavel Begunkov
^ permalink raw reply [flat|nested] 8+ messages in thread