From 232b51948b99dfcc95e81d8a289bc0409b3ff5b3 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 17 Oct 2017 14:16:19 -0700 Subject: [PATCH] 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 Reviewed-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_bmap_util.c | 38 +++---------- fs/xfs/xfs_bmap_util.h | 10 +++- fs/xfs/xfs_ioctl.c | 124 ++++++++++++++++++++--------------------- 3 files changed, 76 insertions(+), 96 deletions(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 2564b8b33e99..0543423651ff 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -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; } diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h index 7d330b3c77c3..4d4ae48bd4f6 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 aa75389be8cf..b01a19844799 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -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);