xfs: simplify the xfs_getbmap interface

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>
This commit is contained in:
Christoph Hellwig 2017-10-17 14:16:19 -07:00 committed by Darrick J. Wong
parent abbf9e8a45
commit 232b51948b
3 changed files with 76 additions and 96 deletions

View File

@ -409,11 +409,11 @@ 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;
@ -460,12 +460,12 @@ 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;
@ -513,47 +513,36 @@ 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)
@ -700,15 +689,6 @@ out_unlock_ilock:
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;
}

View File

@ -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,

View File

@ -1540,17 +1540,26 @@ out_drop_write:
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
@ -1560,68 +1569,57 @@ 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)))
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;
}
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;
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;
buf = kmem_zalloc_large(bmx.bmv_count * sizeof(*buf), 0);
if (!buf)
return -ENOMEM;
error = xfs_getbmap(XFS_I(file_inode(file)), &bmx, xfs_getbmap_format,
(__force struct getbmap *)arg+1);
error = xfs_getbmap(XFS_I(file_inode(file)), &bmx, buf);
if (error)
return error;
goto out_free_buf;
/* copy back header - only size of getbmap */
if (copy_to_user(arg, &bmx, sizeof(struct getbmap)))
return -EFAULT;
return 0;
}
error = -EFAULT;
if (copy_to_user(arg, &bmx, recsize))
goto out_free_buf;
arg += recsize;
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)))
return -EFAULT;
if (bmx.bmv_count < 2)
return -EINVAL;
if (bmx.bmv_iflags & (~BMV_IF_VALID))
return -EINVAL;
error = xfs_getbmap(ip, &bmx, xfs_getbmapx_format,
(__force struct getbmapx *)arg+1);
if (error)
return error;
/* copy back header */
if (copy_to_user(arg, &bmx, sizeof(struct getbmapx)))
return -EFAULT;
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;
}
@ -1878,10 +1876,8 @@ 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);