From c62858108ce52ff83b9099c9c1888f0b89abb5a4 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 17 Oct 2017 14:16:19 -0700
Subject: [PATCH 10/77] xfs: simplify the xfs_getbmap interface
Git-commit: 232b51948b99dfcc95e81d8a289bc0409b3ff5b3
Patch-mainline: v4.15-rc1
References: bsc#1095344
Instead of passing in a formatter callback allocate the bmap buffer
in the caller and process the entries there. Additionally replace
the in-kernel buffer with a new much smaller structure, and unify
the implementation of the different ioctls in a single function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
fs/xfs/xfs_bmap_util.c | 38 ++++-----------
fs/xfs/xfs_bmap_util.h | 10 ++--
fs/xfs/xfs_ioctl.c | 122 ++++++++++++++++++++++++-------------------------
3 files changed, 75 insertions(+), 95 deletions(-)
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index db951747e356..196890eb5433 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -391,11 +391,11 @@ static int
xfs_getbmap_report_one(
struct xfs_inode *ip,
struct getbmapx *bmv,
- struct getbmapx *out,
+ struct kgetbmap *out,
int64_t bmv_end,
struct xfs_bmbt_irec *got)
{
- struct getbmapx *p = out + bmv->bmv_entries;
+ struct kgetbmap *p = out + bmv->bmv_entries;
bool shared = false, trimmed = false;
int error;
@@ -442,12 +442,12 @@ static void
xfs_getbmap_report_hole(
struct xfs_inode *ip,
struct getbmapx *bmv,
- struct getbmapx *out,
+ struct kgetbmap *out,
int64_t bmv_end,
xfs_fileoff_t bno,
xfs_fileoff_t end)
{
- struct getbmapx *p = out + bmv->bmv_entries;
+ struct kgetbmap *p = out + bmv->bmv_entries;
if (bmv->bmv_iflags & BMV_IF_NO_HOLES)
return;
@@ -495,47 +495,36 @@ xfs_getbmap_next_rec(
*/
int /* error code */
xfs_getbmap(
- xfs_inode_t *ip,
+ struct xfs_inode *ip,
struct getbmapx *bmv, /* user bmap structure */
- xfs_bmap_format_t formatter, /* format to user */
- void *arg) /* formatter arg */
+ struct kgetbmap *out)
{
struct xfs_mount *mp = ip->i_mount;
int iflags = bmv->bmv_iflags;
- int whichfork, lock, i, error = 0;
+ int whichfork, lock, error = 0;
int64_t bmv_end, max_len;
xfs_fileoff_t bno, first_bno;
struct xfs_ifork *ifp;
- struct getbmapx *out;
struct xfs_bmbt_irec got, rec;
xfs_filblks_t len;
xfs_extnum_t idx;
+ if (bmv->bmv_iflags & ~BMV_IF_VALID)
+ return -EINVAL;
#ifndef DEBUG
/* Only allow CoW fork queries if we're debugging. */
if (iflags & BMV_IF_COWFORK)
return -EINVAL;
#endif
-
if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK))
return -EINVAL;
- if (bmv->bmv_count <= 1)
- return -EINVAL;
- if (bmv->bmv_count > ULONG_MAX / sizeof(struct getbmapx))
- return -ENOMEM;
-
if (bmv->bmv_length < -1)
return -EINVAL;
-
bmv->bmv_entries = 0;
if (bmv->bmv_length == 0)
return 0;
- out = kmem_zalloc_large(bmv->bmv_count * sizeof(struct getbmapx), 0);
- if (!out)
- return -ENOMEM;
-
if (iflags & BMV_IF_ATTRFORK)
whichfork = XFS_ATTR_FORK;
else if (iflags & BMV_IF_COWFORK)
@@ -682,15 +671,6 @@ xfs_getbmap(
xfs_iunlock(ip, lock);
out_unlock_iolock:
xfs_iunlock(ip, XFS_IOLOCK_SHARED);
-
- for (i = 0; i < bmv->bmv_entries; i++) {
- /* format results & advance arg */
- error = formatter(&arg, &out[i]);
- if (error)
- break;
- }
-
- kmem_free(out);
return error;
}
diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
index ec09b1a20685..79a637630948 100644
--- a/fs/xfs/xfs_bmap_util.h
+++ b/fs/xfs/xfs_bmap_util.h
@@ -47,10 +47,14 @@ int xfs_bmap_eof(struct xfs_inode *ip, xfs_fileoff_t endoff,
int xfs_bmap_punch_delalloc_range(struct xfs_inode *ip,
xfs_fileoff_t start_fsb, xfs_fileoff_t length);
-/* bmap to userspace formatter - copy to user & advance pointer */
-typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *);
+struct kgetbmap {
+ __s64 bmv_offset; /* file offset of segment in blocks */
+ __s64 bmv_block; /* starting block (64-bit daddr_t) */
+ __s64 bmv_length; /* length of segment, blocks */
+ __s32 bmv_oflags; /* output flags */
+};
int xfs_getbmap(struct xfs_inode *ip, struct getbmapx *bmv,
- xfs_bmap_format_t formatter, void *arg);
+ struct kgetbmap *out);
/* functions in xfs_bmap.c that are only needed by xfs_bmap_util.c */
int xfs_bmap_extsize_align(struct xfs_mount *mp, struct xfs_bmbt_irec *gotp,
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index e67864b2a145..55ad0a1ad2e8 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1542,17 +1542,26 @@ xfs_ioc_setxflags(
return error;
}
-STATIC int
-xfs_getbmap_format(void **ap, struct getbmapx *bmv)
+static bool
+xfs_getbmap_format(
+ struct kgetbmap *p,
+ struct getbmapx __user *u,
+ size_t recsize)
{
- struct getbmap __user *base = (struct getbmap __user *)*ap;
-
- /* copy only getbmap portion (not getbmapx) */
- if (copy_to_user(base, bmv, sizeof(struct getbmap)))
- return -EFAULT;
-
- *ap += sizeof(struct getbmap);
- return 0;
+ if (put_user(p->bmv_offset, &u->bmv_offset) ||
+ put_user(p->bmv_block, &u->bmv_block) ||
+ put_user(p->bmv_length, &u->bmv_length) ||
+ put_user(0, &u->bmv_count) ||
+ put_user(0, &u->bmv_entries))
+ return false;
+ if (recsize < sizeof(struct getbmapx))
+ return true;
+ if (put_user(0, &u->bmv_iflags) ||
+ put_user(p->bmv_oflags, &u->bmv_oflags) ||
+ put_user(0, &u->bmv_unused1) ||
+ put_user(0, &u->bmv_unused2))
+ return false;
+ return true;
}
STATIC int
@@ -1562,68 +1571,57 @@ xfs_ioc_getbmap(
void __user *arg)
{
struct getbmapx bmx = { 0 };
- int error;
+ struct kgetbmap *buf;
+ size_t recsize;
+ int error, i;
- /* struct getbmap is a strict subset of struct getbmapx. */
- if (copy_from_user(&bmx, arg, offsetof(struct getbmapx, bmv_iflags)))
- return -EFAULT;
-
- if (bmx.bmv_count < 2)
+ switch (cmd) {
+ case XFS_IOC_GETBMAPA:
+ bmx.bmv_iflags = BMV_IF_ATTRFORK;
+ /*FALLTHRU*/
+ case XFS_IOC_GETBMAP:
+ if (file->f_mode & FMODE_NOCMTIME)
+ bmx.bmv_iflags |= BMV_IF_NO_DMAPI_READ;
+ /* struct getbmap is a strict subset of struct getbmapx. */
+ recsize = sizeof(struct getbmap);
+ break;
+ case XFS_IOC_GETBMAPX:
+ recsize = sizeof(struct getbmapx);
+ break;
+ default:
return -EINVAL;
+ }
- bmx.bmv_iflags = (cmd == XFS_IOC_GETBMAPA ? BMV_IF_ATTRFORK : 0);
- if (file->f_mode & FMODE_NOCMTIME)
- bmx.bmv_iflags |= BMV_IF_NO_DMAPI_READ;
-
- error = xfs_getbmap(XFS_I(file_inode(file)), &bmx, xfs_getbmap_format,
- (__force struct getbmap *)arg+1);
- if (error)
- return error;
-
- /* copy back header - only size of getbmap */
- if (copy_to_user(arg, &bmx, sizeof(struct getbmap)))
- return -EFAULT;
- return 0;
-}
-
-STATIC int
-xfs_getbmapx_format(void **ap, struct getbmapx *bmv)
-{
- struct getbmapx __user *base = (struct getbmapx __user *)*ap;
-
- if (copy_to_user(base, bmv, sizeof(struct getbmapx)))
- return -EFAULT;
-
- *ap += sizeof(struct getbmapx);
- return 0;
-}
-
-STATIC int
-xfs_ioc_getbmapx(
- struct xfs_inode *ip,
- void __user *arg)
-{
- struct getbmapx bmx;
- int error;
-
- if (copy_from_user(&bmx, arg, sizeof(bmx)))
+ if (copy_from_user(&bmx, arg, recsize))
return -EFAULT;
if (bmx.bmv_count < 2)
return -EINVAL;
+ if (bmx.bmv_count > ULONG_MAX / recsize)
+ return -ENOMEM;
- if (bmx.bmv_iflags & (~BMV_IF_VALID))
- return -EINVAL;
+ buf = kmem_zalloc_large(bmx.bmv_count * sizeof(*buf), 0);
+ if (!buf)
+ return -ENOMEM;
- error = xfs_getbmap(ip, &bmx, xfs_getbmapx_format,
- (__force struct getbmapx *)arg+1);
+ error = xfs_getbmap(XFS_I(file_inode(file)), &bmx, buf);
if (error)
- return error;
+ goto out_free_buf;
- /* copy back header */
- if (copy_to_user(arg, &bmx, sizeof(struct getbmapx)))
- return -EFAULT;
+ error = -EFAULT;
+ if (copy_to_user(arg, &bmx, recsize))
+ goto out_free_buf;
+ arg += recsize;
+
+ for (i = 0; i < bmx.bmv_entries; i++) {
+ if (!xfs_getbmap_format(buf + i, arg, recsize))
+ goto out_free_buf;
+ arg += recsize;
+ }
+ error = 0;
+out_free_buf:
+ kmem_free(buf);
return 0;
}
@@ -1880,10 +1878,8 @@ xfs_file_ioctl(
case XFS_IOC_GETBMAP:
case XFS_IOC_GETBMAPA:
- return xfs_ioc_getbmap(filp, cmd, arg);
-
case XFS_IOC_GETBMAPX:
- return xfs_ioc_getbmapx(ip, arg);
+ return xfs_ioc_getbmap(filp, cmd, arg);
case FS_IOC_GETFSMAP:
return xfs_ioc_getfsmap(ip, arg);
--
2.7.4