Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3) #include "fuse_i.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5) #include <linux/fuse.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) #include <linux/idr.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #include <linux/uio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #define PASSTHROUGH_IOCB_MASK                                                  \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) 	(IOCB_APPEND | IOCB_DSYNC | IOCB_HIPRI | IOCB_NOWAIT | IOCB_SYNC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) struct fuse_aio_req {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) 	struct kiocb iocb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 	struct kiocb *iocb_fuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) static void fuse_file_accessed(struct file *dst_file, struct file *src_file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 	struct inode *dst_inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 	struct inode *src_inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	if (dst_file->f_flags & O_NOATIME)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	dst_inode = file_inode(dst_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	src_inode = file_inode(src_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	if ((!timespec64_equal(&dst_inode->i_mtime, &src_inode->i_mtime) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	     !timespec64_equal(&dst_inode->i_ctime, &src_inode->i_ctime))) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 		dst_inode->i_mtime = src_inode->i_mtime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 		dst_inode->i_ctime = src_inode->i_ctime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	touch_atime(&dst_file->f_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) static void fuse_copyattr(struct file *dst_file, struct file *src_file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	struct inode *dst = file_inode(dst_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	struct inode *src = file_inode(src_file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	dst->i_atime = src->i_atime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	dst->i_mtime = src->i_mtime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	dst->i_ctime = src->i_ctime;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	i_size_write(dst, i_size_read(src));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) static void fuse_aio_cleanup_handler(struct fuse_aio_req *aio_req)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	struct kiocb *iocb = &aio_req->iocb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	struct kiocb *iocb_fuse = aio_req->iocb_fuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	if (iocb->ki_flags & IOCB_WRITE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 		__sb_writers_acquired(file_inode(iocb->ki_filp)->i_sb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 				      SB_FREEZE_WRITE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 		file_end_write(iocb->ki_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 		fuse_copyattr(iocb_fuse->ki_filp, iocb->ki_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	iocb_fuse->ki_pos = iocb->ki_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	kfree(aio_req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) static void fuse_aio_rw_complete(struct kiocb *iocb, long res, long res2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	struct fuse_aio_req *aio_req =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 		container_of(iocb, struct fuse_aio_req, iocb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	struct kiocb *iocb_fuse = aio_req->iocb_fuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	fuse_aio_cleanup_handler(aio_req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	iocb_fuse->ki_complete(iocb_fuse, res, res2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) ssize_t fuse_passthrough_read_iter(struct kiocb *iocb_fuse,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 				   struct iov_iter *iter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	ssize_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 	const struct cred *old_cred;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	struct file *fuse_filp = iocb_fuse->ki_filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	struct fuse_file *ff = fuse_filp->private_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	struct file *passthrough_filp = ff->passthrough.filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	if (!iov_iter_count(iter))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	old_cred = override_creds(ff->passthrough.cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	if (is_sync_kiocb(iocb_fuse)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 		ret = vfs_iter_read(passthrough_filp, iter, &iocb_fuse->ki_pos,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 				    iocb_to_rw_flags(iocb_fuse->ki_flags,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 						     PASSTHROUGH_IOCB_MASK));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 		struct fuse_aio_req *aio_req;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 		aio_req = kmalloc(sizeof(struct fuse_aio_req), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 		if (!aio_req) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 			ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		aio_req->iocb_fuse = iocb_fuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		kiocb_clone(&aio_req->iocb, iocb_fuse, passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		aio_req->iocb.ki_complete = fuse_aio_rw_complete;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		ret = call_read_iter(passthrough_filp, &aio_req->iocb, iter);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		if (ret != -EIOCBQUEUED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 			fuse_aio_cleanup_handler(aio_req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	revert_creds(old_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	fuse_file_accessed(fuse_filp, passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) ssize_t fuse_passthrough_write_iter(struct kiocb *iocb_fuse,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 				    struct iov_iter *iter)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	ssize_t ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	const struct cred *old_cred;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	struct file *fuse_filp = iocb_fuse->ki_filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	struct fuse_file *ff = fuse_filp->private_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	struct inode *fuse_inode = file_inode(fuse_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	struct file *passthrough_filp = ff->passthrough.filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	struct inode *passthrough_inode = file_inode(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	if (!iov_iter_count(iter))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	inode_lock(fuse_inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	fuse_copyattr(fuse_filp, passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	old_cred = override_creds(ff->passthrough.cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	if (is_sync_kiocb(iocb_fuse)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 		file_start_write(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 		ret = vfs_iter_write(passthrough_filp, iter, &iocb_fuse->ki_pos,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 				     iocb_to_rw_flags(iocb_fuse->ki_flags,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 						      PASSTHROUGH_IOCB_MASK));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 		file_end_write(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 		if (ret > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 			fuse_copyattr(fuse_filp, passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		struct fuse_aio_req *aio_req;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 		aio_req = kmalloc(sizeof(struct fuse_aio_req), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 		if (!aio_req) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 			ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 		file_start_write(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 		__sb_writers_release(passthrough_inode->i_sb, SB_FREEZE_WRITE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 		aio_req->iocb_fuse = iocb_fuse;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 		kiocb_clone(&aio_req->iocb, iocb_fuse, passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 		aio_req->iocb.ki_complete = fuse_aio_rw_complete;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 		ret = call_write_iter(passthrough_filp, &aio_req->iocb, iter);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 		if (ret != -EIOCBQUEUED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 			fuse_aio_cleanup_handler(aio_req);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	revert_creds(old_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	inode_unlock(fuse_inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) ssize_t fuse_passthrough_mmap(struct file *file, struct vm_area_struct *vma)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	const struct cred *old_cred;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	struct fuse_file *ff = file->private_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	struct file *passthrough_filp = ff->passthrough.filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	if (!passthrough_filp->f_op->mmap)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	if (WARN_ON(file != vma->vm_file))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	vma->vm_file = get_file(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	old_cred = override_creds(ff->passthrough.cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	ret = call_mmap(vma->vm_file, vma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	revert_creds(old_cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 		fput(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 		fput(file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	fuse_file_accessed(file, passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) int fuse_passthrough_open(struct fuse_dev *fud, u32 lower_fd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 	int res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 	struct file *passthrough_filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 	struct fuse_conn *fc = fud->fc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 	struct inode *passthrough_inode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	struct super_block *passthrough_sb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 	struct fuse_passthrough *passthrough;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	if (!fc->passthrough)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 		return -EPERM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 	passthrough_filp = fget(lower_fd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 	if (!passthrough_filp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 		pr_err("FUSE: invalid file descriptor for passthrough.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 		return -EBADF;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 	if (!passthrough_filp->f_op->read_iter ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	    !passthrough_filp->f_op->write_iter) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 		pr_err("FUSE: passthrough file misses file operations.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 		res = -EBADF;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 		goto err_free_file;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 	passthrough_inode = file_inode(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 	passthrough_sb = passthrough_inode->i_sb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 	if (passthrough_sb->s_stack_depth >= FILESYSTEM_MAX_STACK_DEPTH) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 		pr_err("FUSE: fs stacking depth exceeded for passthrough\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 		res = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 		goto err_free_file;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 	passthrough = kmalloc(sizeof(struct fuse_passthrough), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 	if (!passthrough) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 		res = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 		goto err_free_file;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 	passthrough->filp = passthrough_filp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 	passthrough->cred = prepare_creds();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 	idr_preload(GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 	spin_lock(&fc->passthrough_req_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 	res = idr_alloc(&fc->passthrough_req, passthrough, 1, 0, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 	spin_unlock(&fc->passthrough_req_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 	idr_preload_end();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	if (res > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 		return res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	fuse_passthrough_release(passthrough);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 	kfree(passthrough);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) err_free_file:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	fput(passthrough_filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 	return res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) int fuse_passthrough_setup(struct fuse_conn *fc, struct fuse_file *ff,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 			   struct fuse_open_out *openarg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 	struct fuse_passthrough *passthrough;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	int passthrough_fh = openarg->passthrough_fh;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 	if (!fc->passthrough)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 		return -EPERM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 	/* Default case, passthrough is not requested */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 	if (passthrough_fh <= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 	spin_lock(&fc->passthrough_req_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	passthrough = idr_remove(&fc->passthrough_req, passthrough_fh);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 	spin_unlock(&fc->passthrough_req_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 	if (!passthrough)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 	ff->passthrough = *passthrough;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 	kfree(passthrough);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) void fuse_passthrough_release(struct fuse_passthrough *passthrough)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 	if (passthrough->filp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 		fput(passthrough->filp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 		passthrough->filp = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 	if (passthrough->cred) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 		put_cred(passthrough->cred);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 		passthrough->cred = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) }