mirror of
https://git.proxmox.com/git/mirror_zfs.git
synced 2026-05-24 19:28:53 +03:00
Linux 4.1 compat: loop device on ZFS
Starting from Linux 4.1 allows iov_iter with bio_vec to be passed into iter_read/iter_write. Notably, the loop device will pass bio_vec to backend filesystem. However, current ZFS code assumes iovec without any check, so it will always crash when using loop device. With the restructured uio_t, we can safely pass bio_vec in uio_t with UIO_BVEC set. The uio* functions are modified to handle bio_vec case separately. The const uio_iov causes some warning in xuio related stuff, so explicit convert them to non const. Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #3511 Closes #3640
This commit is contained in:
Chunwei Chen
committed by
Brian Behlendorf
Brian Behlendorf
parent
17888ae30d
commit
5475aada94
+3
-2
@@ -23,6 +23,7 @@
|
||||
* Copyright (c) 2011, 2014 by Delphix. All rights reserved.
|
||||
* Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
|
||||
* Copyright (c) 2014, Nexenta Systems, Inc. All rights reserved.
|
||||
* Copyright (c) 2015 by Chunwei Chen. All rights reserved.
|
||||
*/
|
||||
|
||||
#include <sys/dmu.h>
|
||||
@@ -933,7 +934,7 @@ dmu_xuio_init(xuio_t *xuio, int nblk)
|
||||
priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_SLEEP);
|
||||
priv->cnt = nblk;
|
||||
priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_SLEEP);
|
||||
priv->iovp = uio->uio_iov;
|
||||
priv->iovp = (iovec_t *)uio->uio_iov;
|
||||
XUIO_XUZC_PRIV(xuio) = priv;
|
||||
|
||||
if (XUIO_XUZC_RW(xuio) == UIO_READ)
|
||||
@@ -974,7 +975,7 @@ dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n)
|
||||
|
||||
ASSERT(i < priv->cnt);
|
||||
ASSERT(off + n <= arc_buf_size(abuf));
|
||||
iov = uio->uio_iov + i;
|
||||
iov = (iovec_t *)uio->uio_iov + i;
|
||||
iov->iov_base = (char *)abuf->b_data + off;
|
||||
iov->iov_len = n;
|
||||
priv->bufs[i] = abuf;
|
||||
|
||||
@@ -21,6 +21,7 @@
|
||||
/*
|
||||
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
|
||||
* Copyright (c) 2013 by Delphix. All rights reserved.
|
||||
* Copyright (c) 2015 by Chunwei Chen. All rights reserved.
|
||||
*/
|
||||
|
||||
/* Portions Copyright 2007 Jeremy Teo */
|
||||
@@ -591,10 +592,10 @@ zfs_write(struct inode *ip, uio_t *uio, int ioflag, cred_t *cr)
|
||||
int max_blksz = zsb->z_max_blksz;
|
||||
int error = 0;
|
||||
arc_buf_t *abuf;
|
||||
iovec_t *aiov = NULL;
|
||||
const iovec_t *aiov = NULL;
|
||||
xuio_t *xuio = NULL;
|
||||
int i_iov = 0;
|
||||
iovec_t *iovp = uio->uio_iov;
|
||||
const iovec_t *iovp = uio->uio_iov;
|
||||
int write_eof;
|
||||
int count = 0;
|
||||
sa_bulk_attr_t bulk[4];
|
||||
@@ -714,6 +715,7 @@ zfs_write(struct inode *ip, uio_t *uio, int ioflag, cred_t *cr)
|
||||
|
||||
if (xuio && abuf == NULL) {
|
||||
ASSERT(i_iov < iovcnt);
|
||||
ASSERT3U(uio->uio_segflg, !=, UIO_BVEC);
|
||||
aiov = &iovp[i_iov];
|
||||
abuf = dmu_xuio_arcbuf(xuio, i_iov);
|
||||
dmu_xuio_clear(xuio, i_iov);
|
||||
|
||||
+45
-36
@@ -20,6 +20,7 @@
|
||||
*/
|
||||
/*
|
||||
* Copyright (c) 2011, Lawrence Livermore National Security, LLC.
|
||||
* Copyright (c) 2015 by Chunwei Chen. All rights reserved.
|
||||
*/
|
||||
|
||||
|
||||
@@ -202,17 +203,18 @@ zpl_aio_fsync(struct kiocb *kiocb, int datasync)
|
||||
#error "Unsupported fops->fsync() implementation"
|
||||
#endif
|
||||
|
||||
static inline ssize_t
|
||||
static ssize_t
|
||||
zpl_read_common_iovec(struct inode *ip, const struct iovec *iovp, size_t count,
|
||||
unsigned long nr_segs, loff_t *ppos, uio_seg_t segment,
|
||||
int flags, cred_t *cr)
|
||||
unsigned long nr_segs, loff_t *ppos, uio_seg_t segment, int flags,
|
||||
cred_t *cr, size_t skip)
|
||||
{
|
||||
ssize_t read;
|
||||
uio_t uio;
|
||||
int error;
|
||||
fstrans_cookie_t cookie;
|
||||
|
||||
uio.uio_iov = (struct iovec *)iovp;
|
||||
uio.uio_iov = iovp;
|
||||
uio.uio_skip = skip;
|
||||
uio.uio_resid = count;
|
||||
uio.uio_iovcnt = nr_segs;
|
||||
uio.uio_loffset = *ppos;
|
||||
@@ -242,7 +244,7 @@ zpl_read_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos,
|
||||
iov.iov_len = len;
|
||||
|
||||
return (zpl_read_common_iovec(ip, &iov, len, 1, ppos, segment,
|
||||
flags, cr));
|
||||
flags, cr, 0));
|
||||
}
|
||||
|
||||
static ssize_t
|
||||
@@ -261,24 +263,17 @@ zpl_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
|
||||
|
||||
static ssize_t
|
||||
zpl_iter_read_common(struct kiocb *kiocb, const struct iovec *iovp,
|
||||
unsigned long nr_segs, size_t count)
|
||||
unsigned long nr_segs, size_t count, uio_seg_t seg, size_t skip)
|
||||
{
|
||||
cred_t *cr = CRED();
|
||||
struct file *filp = kiocb->ki_filp;
|
||||
ssize_t read;
|
||||
size_t alloc_size = sizeof (struct iovec) * nr_segs;
|
||||
struct iovec *iov_tmp = kmem_alloc(alloc_size, KM_SLEEP);
|
||||
bcopy(iovp, iov_tmp, alloc_size);
|
||||
|
||||
ASSERT(iovp);
|
||||
|
||||
crhold(cr);
|
||||
read = zpl_read_common_iovec(filp->f_mapping->host, iov_tmp, count,
|
||||
nr_segs, &kiocb->ki_pos, UIO_USERSPACE, filp->f_flags, cr);
|
||||
read = zpl_read_common_iovec(filp->f_mapping->host, iovp, count,
|
||||
nr_segs, &kiocb->ki_pos, seg, filp->f_flags, cr, skip);
|
||||
crfree(cr);
|
||||
|
||||
kmem_free(iov_tmp, alloc_size);
|
||||
|
||||
return (read);
|
||||
}
|
||||
|
||||
@@ -286,22 +281,32 @@ zpl_iter_read_common(struct kiocb *kiocb, const struct iovec *iovp,
|
||||
static ssize_t
|
||||
zpl_iter_read(struct kiocb *kiocb, struct iov_iter *to)
|
||||
{
|
||||
return (zpl_iter_read_common(kiocb, to->iov, to->nr_segs,
|
||||
iov_iter_count(to)));
|
||||
ssize_t ret;
|
||||
uio_seg_t seg = UIO_USERSPACE;
|
||||
if (to->type & ITER_KVEC)
|
||||
seg = UIO_SYSSPACE;
|
||||
if (to->type & ITER_BVEC)
|
||||
seg = UIO_BVEC;
|
||||
ret = zpl_iter_read_common(kiocb, to->iov, to->nr_segs,
|
||||
iov_iter_count(to), seg, to->iov_offset);
|
||||
if (ret > 0)
|
||||
iov_iter_advance(to, ret);
|
||||
return (ret);
|
||||
}
|
||||
#else
|
||||
static ssize_t
|
||||
zpl_aio_read(struct kiocb *kiocb, const struct iovec *iovp,
|
||||
unsigned long nr_segs, loff_t pos)
|
||||
{
|
||||
return (zpl_iter_read_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes));
|
||||
return (zpl_iter_read_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes,
|
||||
UIO_USERSPACE, 0));
|
||||
}
|
||||
#endif /* HAVE_VFS_RW_ITERATE */
|
||||
|
||||
static inline ssize_t
|
||||
static ssize_t
|
||||
zpl_write_common_iovec(struct inode *ip, const struct iovec *iovp, size_t count,
|
||||
unsigned long nr_segs, loff_t *ppos, uio_seg_t segment,
|
||||
int flags, cred_t *cr)
|
||||
unsigned long nr_segs, loff_t *ppos, uio_seg_t segment, int flags,
|
||||
cred_t *cr, size_t skip)
|
||||
{
|
||||
ssize_t wrote;
|
||||
uio_t uio;
|
||||
@@ -311,7 +316,8 @@ zpl_write_common_iovec(struct inode *ip, const struct iovec *iovp, size_t count,
|
||||
if (flags & O_APPEND)
|
||||
*ppos = i_size_read(ip);
|
||||
|
||||
uio.uio_iov = (struct iovec *)iovp;
|
||||
uio.uio_iov = iovp;
|
||||
uio.uio_skip = skip;
|
||||
uio.uio_resid = count;
|
||||
uio.uio_iovcnt = nr_segs;
|
||||
uio.uio_loffset = *ppos;
|
||||
@@ -340,7 +346,7 @@ zpl_write_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos,
|
||||
iov.iov_len = len;
|
||||
|
||||
return (zpl_write_common_iovec(ip, &iov, len, 1, ppos, segment,
|
||||
flags, cr));
|
||||
flags, cr, 0));
|
||||
}
|
||||
|
||||
static ssize_t
|
||||
@@ -359,24 +365,17 @@ zpl_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos)
|
||||
|
||||
static ssize_t
|
||||
zpl_iter_write_common(struct kiocb *kiocb, const struct iovec *iovp,
|
||||
unsigned long nr_segs, size_t count)
|
||||
unsigned long nr_segs, size_t count, uio_seg_t seg, size_t skip)
|
||||
{
|
||||
cred_t *cr = CRED();
|
||||
struct file *filp = kiocb->ki_filp;
|
||||
ssize_t wrote;
|
||||
size_t alloc_size = sizeof (struct iovec) * nr_segs;
|
||||
struct iovec *iov_tmp = kmem_alloc(alloc_size, KM_SLEEP);
|
||||
bcopy(iovp, iov_tmp, alloc_size);
|
||||
|
||||
ASSERT(iovp);
|
||||
|
||||
crhold(cr);
|
||||
wrote = zpl_write_common_iovec(filp->f_mapping->host, iov_tmp, count,
|
||||
nr_segs, &kiocb->ki_pos, UIO_USERSPACE, filp->f_flags, cr);
|
||||
wrote = zpl_write_common_iovec(filp->f_mapping->host, iovp, count,
|
||||
nr_segs, &kiocb->ki_pos, seg, filp->f_flags, cr, skip);
|
||||
crfree(cr);
|
||||
|
||||
kmem_free(iov_tmp, alloc_size);
|
||||
|
||||
return (wrote);
|
||||
}
|
||||
|
||||
@@ -384,15 +383,25 @@ zpl_iter_write_common(struct kiocb *kiocb, const struct iovec *iovp,
|
||||
static ssize_t
|
||||
zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from)
|
||||
{
|
||||
return (zpl_iter_write_common(kiocb, from->iov, from->nr_segs,
|
||||
iov_iter_count(from)));
|
||||
ssize_t ret;
|
||||
uio_seg_t seg = UIO_USERSPACE;
|
||||
if (from->type & ITER_KVEC)
|
||||
seg = UIO_SYSSPACE;
|
||||
if (from->type & ITER_BVEC)
|
||||
seg = UIO_BVEC;
|
||||
ret = zpl_iter_write_common(kiocb, from->iov, from->nr_segs,
|
||||
iov_iter_count(from), seg, from->iov_offset);
|
||||
if (ret > 0)
|
||||
iov_iter_advance(from, ret);
|
||||
return (ret);
|
||||
}
|
||||
#else
|
||||
static ssize_t
|
||||
zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp,
|
||||
unsigned long nr_segs, loff_t pos)
|
||||
{
|
||||
return (zpl_iter_write_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes));
|
||||
return (zpl_iter_write_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes,
|
||||
UIO_USERSPACE, 0));
|
||||
}
|
||||
#endif /* HAVE_VFS_RW_ITERATE */
|
||||
|
||||
|
||||
@@ -20,6 +20,7 @@
|
||||
*/
|
||||
/*
|
||||
* Copyright (c) 2011, Lawrence Livermore National Security, LLC.
|
||||
* Copyright (c) 2015 by Chunwei Chen. All rights reserved.
|
||||
*/
|
||||
|
||||
|
||||
@@ -371,6 +372,7 @@ zpl_follow_link(struct dentry *dentry, void **symlink_cookie)
|
||||
|
||||
uio.uio_iov = &iov;
|
||||
uio.uio_iovcnt = 1;
|
||||
uio.uio_skip = 0;
|
||||
uio.uio_resid = (MAXPATHLEN - 1);
|
||||
uio.uio_segflg = UIO_SYSSPACE;
|
||||
|
||||
|
||||
Reference in New Issue
Block a user