| Message ID | 20220611094200.129502-18-allison.henderson@oracle.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Return of the Parent Pointers | expand |
On Sat, Jun 11, 2022 at 02:42:00AM -0700, Allison Henderson wrote: > This patch adds a new file ioctl to retrieve the parent pointer of a > given inode > > Signed-off-by: Allison Henderson <allison.henderson@oracle.com> > --- > fs/xfs/Makefile | 1 + > fs/xfs/libxfs/xfs_fs.h | 46 +++++++++++++ > fs/xfs/libxfs/xfs_parent.c | 10 +++ > fs/xfs/libxfs/xfs_parent.h | 2 + > fs/xfs/xfs_ioctl.c | 90 ++++++++++++++++++++++++- > fs/xfs/xfs_ondisk.h | 4 ++ > fs/xfs/xfs_parent_utils.c | 133 +++++++++++++++++++++++++++++++++++++ > fs/xfs/xfs_parent_utils.h | 22 ++++++ > 8 files changed, 306 insertions(+), 2 deletions(-) > > diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile > index fc717dc3470c..da86f6231f2e 100644 > --- a/fs/xfs/Makefile > +++ b/fs/xfs/Makefile > @@ -86,6 +86,7 @@ xfs-y += xfs_aops.o \ > xfs_mount.o \ > xfs_mru_cache.o \ > xfs_pwork.o \ > + xfs_parent_utils.o \ > xfs_reflink.o \ > xfs_stats.o \ > xfs_super.o \ > diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h > index b0b4d7a3aa15..e6c8873cd234 100644 > --- a/fs/xfs/libxfs/xfs_fs.h > +++ b/fs/xfs/libxfs/xfs_fs.h > @@ -574,6 +574,7 @@ typedef struct xfs_fsop_handlereq { > #define XFS_IOC_ATTR_SECURE 0x0008 /* use attrs in security namespace */ > #define XFS_IOC_ATTR_CREATE 0x0010 /* fail if attr already exists */ > #define XFS_IOC_ATTR_REPLACE 0x0020 /* fail if attr does not exist */ > +#define XFS_IOC_ATTR_PARENT 0x0040 /* use attrs in parent namespace */ > > typedef struct xfs_attrlist_cursor { > __u32 opaque[4]; > @@ -752,6 +753,50 @@ struct xfs_scrub_metadata { > XFS_SCRUB_OFLAG_NO_REPAIR_NEEDED) > #define XFS_SCRUB_FLAGS_ALL (XFS_SCRUB_FLAGS_IN | XFS_SCRUB_FLAGS_OUT) > > +#define XFS_PPTR_MAXNAMELEN 256 > + > +/* return parents of the handle, not the open fd */ > +#define XFS_PPTR_IFLAG_HANDLE (1U << 0) > + > +/* target was the root directory */ > +#define XFS_PPTR_OFLAG_ROOT (1U << 1) > + > +/* Cursor is done iterating pptrs */ > +#define XFS_PPTR_OFLAG_DONE (1U << 2) > + > +/* Get an inode parent pointer through ioctl */ > +struct xfs_parent_ptr { > + __u64 xpp_ino; /* Inode */ > + __u32 xpp_gen; /* Inode generation */ > + __u32 xpp_diroffset; /* Directory offset */ > + __u32 xpp_namelen; /* File name length */ > + __u32 xpp_pad; > + __u8 xpp_name[XFS_PPTR_MAXNAMELEN]; /* File name */ > +}; > + > +/* Iterate through an inodes parent pointers */ > +struct xfs_pptr_info { > + struct xfs_handle pi_handle; > + struct xfs_attrlist_cursor pi_cursor; > + __u32 pi_flags; > + __u32 pi_reserved; > + __u32 pi_ptrs_size; > + __u32 pi_ptrs_used; > + __u64 pi_reserved2[6]; > + > + /* > + * An array of struct xfs_parent_ptr follows the header > + * information. Use XFS_PPINFO_TO_PP() to access the > + * parent pointer array entries. > + */ struct xfs_parent_ptr pi_parents[]; Unless you want to conserve space in the userspace buffer by making the size of xfs_parent_ptr itself variable? Userspace would have to walk the entire buffer by hand like it does for listxattr, but it saves a fair amount of space. > +}; > + > +#define XFS_PPTR_INFO_SIZEOF(nr_ptrs) sizeof (struct xfs_pptr_info) + \ > + nr_ptrs * sizeof(struct xfs_parent_ptr) > + > +#define XFS_PPINFO_TO_PP(info, idx) \ > + (&(((struct xfs_parent_ptr *)((char *)(info) + sizeof(*(info))))[(idx)])) Turn these into static inline functions so that client programs get some proper typechecking by the C compiler. > + > /* > * ioctl limits > */ > @@ -797,6 +842,7 @@ struct xfs_scrub_metadata { > /* XFS_IOC_GETFSMAP ------ hoisted 59 */ > #define XFS_IOC_SCRUB_METADATA _IOWR('X', 60, struct xfs_scrub_metadata) > #define XFS_IOC_AG_GEOMETRY _IOWR('X', 61, struct xfs_ag_geometry) > +#define XFS_IOC_GETPPOINTER _IOR ('X', 62, struct xfs_parent_ptr) > > /* > * ioctl commands that replace IRIX syssgi()'s > diff --git a/fs/xfs/libxfs/xfs_parent.c b/fs/xfs/libxfs/xfs_parent.c > index cb546652bde9..a5b99f30bc63 100644 > --- a/fs/xfs/libxfs/xfs_parent.c > +++ b/fs/xfs/libxfs/xfs_parent.c > @@ -33,6 +33,16 @@ > #include "xfs_attr_sf.h" > #include "xfs_bmap.h" > > +/* Initializes a xfs_parent_ptr from an xfs_parent_name_rec */ > +void > +xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, > + struct xfs_parent_name_rec *rec) Indenting... > +{ > + xpp->xpp_ino = be64_to_cpu(rec->p_ino); > + xpp->xpp_gen = be32_to_cpu(rec->p_gen); > + xpp->xpp_diroffset = be32_to_cpu(rec->p_diroffset); > +} > + > /* > * Parent pointer attribute handling. > * > diff --git a/fs/xfs/libxfs/xfs_parent.h b/fs/xfs/libxfs/xfs_parent.h > index 10dc576ce693..fa50ada0d6a9 100644 > --- a/fs/xfs/libxfs/xfs_parent.h > +++ b/fs/xfs/libxfs/xfs_parent.h > @@ -28,4 +28,6 @@ void xfs_init_parent_name_rec(struct xfs_parent_name_rec *rec, > uint32_t p_diroffset); > void xfs_init_parent_name_irec(struct xfs_parent_name_irec *irec, > struct xfs_parent_name_rec *rec); > +void xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, > + struct xfs_parent_name_rec *rec); > #endif /* __XFS_PARENT_H__ */ > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > index e1612e99e0c5..4cd1de3e9d0b 100644 > --- a/fs/xfs/xfs_ioctl.c > +++ b/fs/xfs/xfs_ioctl.c > @@ -37,6 +37,7 @@ > #include "xfs_health.h" > #include "xfs_reflink.h" > #include "xfs_ioctl.h" > +#include "xfs_parent_utils.h" > #include "xfs_xattr.h" > > #include <linux/mount.h> > @@ -355,6 +356,8 @@ xfs_attr_filter( > return XFS_ATTR_ROOT; > if (ioc_flags & XFS_IOC_ATTR_SECURE) > return XFS_ATTR_SECURE; > + if (ioc_flags & XFS_IOC_ATTR_PARENT) > + return XFS_ATTR_PARENT; > return 0; > } > > @@ -422,7 +425,8 @@ xfs_ioc_attr_list( > /* > * Reject flags, only allow namespaces. > */ > - if (flags & ~(XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE)) > + if (flags & ~(XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE | > + XFS_IOC_ATTR_PARENT)) > return -EINVAL; > if (flags == (XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE)) > return -EINVAL; > @@ -1672,6 +1676,87 @@ xfs_ioc_scrub_metadata( > return 0; > } > > +/* > + * IOCTL routine to get the parent pointers of an inode and return it to user > + * space. Caller must pass a buffer space containing a struct xfs_pptr_info, > + * followed by a region large enough to contain an array of struct > + * xfs_parent_ptr of a size specified in pi_ptrs_size. If the inode contains > + * more parent pointers than can fit in the buffer space, caller may re-call > + * the function using the returned pi_cursor to resume iteration. The > + * number of xfs_parent_ptr returned will be stored in pi_ptrs_used. > + * > + * Returns 0 on success or non-zero on failure > + */ > +STATIC int > +xfs_ioc_get_parent_pointer( > + struct file *filp, > + void __user *arg) > +{ > + struct xfs_pptr_info *ppi = NULL; > + int error = 0; > + struct xfs_inode *ip = XFS_I(file_inode(filp)); > + struct xfs_mount *mp = ip->i_mount; > + > + if (!capable(CAP_SYS_ADMIN)) > + return -EPERM; > + > + /* Allocate an xfs_pptr_info to put the user data */ > + ppi = kmem_alloc(sizeof(struct xfs_pptr_info), 0); > + if (!ppi) > + return -ENOMEM; > + > + /* Copy the data from the user */ > + error = copy_from_user(ppi, arg, sizeof(struct xfs_pptr_info)); > + if (error) > + goto out; > + > + /* Check size of buffer requested by user */ > + if (XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size) > XFS_XATTR_LIST_MAX) { > + error = -ENOMEM; > + goto out; > + } > + > + /* > + * Now that we know how big the trailing buffer is, expand > + * our kernel xfs_pptr_info to be the same size > + */ > + ppi = krealloc(ppi, XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size), > + GFP_NOFS | __GFP_NOFAIL); > + if (!ppi) > + return -ENOMEM; > + > + if (ppi->pi_flags != 0 && ppi->pi_flags != XFS_PPTR_IFLAG_HANDLE) { Flags validation should come before the big memory allocation. > + error = -EINVAL; > + goto out; > + } > + > + if (ppi->pi_flags == XFS_PPTR_IFLAG_HANDLE) { > + error = xfs_iget(mp, NULL, ppi->pi_handle.ha_fid.fid_ino, > + 0, 0, &ip); > + if (error) > + goto out; This ought to be checking the generation number in the file handle. > + } > + > + if (ip->i_ino == mp->m_sb.sb_rootino) > + ppi->pi_flags |= XFS_PPTR_OFLAG_ROOT; > + > + /* Get the parent pointers */ > + error = xfs_attr_get_parent_pointer(ip, ppi); > + > + if (error) > + goto out; > + > + /* Copy the parent pointers back to the user */ > + error = copy_to_user(arg, ppi, > + XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size)); > + if (error) > + goto out; > + > +out: > + kmem_free(ppi); > + return error; > +} > + > int > xfs_ioc_swapext( > xfs_swapext_t *sxp) > @@ -1961,7 +2046,8 @@ xfs_file_ioctl( > > case XFS_IOC_FSGETXATTRA: > return xfs_ioc_fsgetxattra(ip, arg); > - > + case XFS_IOC_GETPPOINTER: > + return xfs_ioc_get_parent_pointer(filp, arg); > case XFS_IOC_GETBMAP: > case XFS_IOC_GETBMAPA: > case XFS_IOC_GETBMAPX: > diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h > index 758702b9495f..765eb514a917 100644 > --- a/fs/xfs/xfs_ondisk.h > +++ b/fs/xfs/xfs_ondisk.h > @@ -135,6 +135,10 @@ xfs_check_ondisk_structs(void) > XFS_CHECK_STRUCT_SIZE(struct xfs_attri_log_format, 40); > XFS_CHECK_STRUCT_SIZE(struct xfs_attrd_log_format, 16); > > + /* parent pointer ioctls */ > + XFS_CHECK_STRUCT_SIZE(struct xfs_parent_ptr, 280); > + XFS_CHECK_STRUCT_SIZE(struct xfs_pptr_info, 104); > + > /* > * The v5 superblock format extended several v4 header structures with > * additional data. While new fields are only accessible on v5 > diff --git a/fs/xfs/xfs_parent_utils.c b/fs/xfs/xfs_parent_utils.c > new file mode 100644 > index 000000000000..9880718395c6 > --- /dev/null > +++ b/fs/xfs/xfs_parent_utils.c > @@ -0,0 +1,133 @@ > +/* > + * Copyright (c) 2015 Red Hat, Inc. > + * All rights reserved. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it would be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write the Free Software Foundation > + */ > +#include "xfs.h" > +#include "xfs_fs.h" > +#include "xfs_format.h" > +#include "xfs_log_format.h" > +#include "xfs_shared.h" > +#include "xfs_trans_resv.h" > +#include "xfs_mount.h" > +#include "xfs_bmap_btree.h" > +#include "xfs_inode.h" > +#include "xfs_error.h" > +#include "xfs_trace.h" > +#include "xfs_trans.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > +#include "xfs_attr.h" > +#include "xfs_ioctl.h" > +#include "xfs_parent.h" > +#include "xfs_da_btree.h" > + > +/* > + * Get the parent pointers for a given inode > + * > + * Returns 0 on success and non zero on error > + */ > +int > +xfs_attr_get_parent_pointer(struct xfs_inode *ip, > + struct xfs_pptr_info *ppi) > + Indenting. Also, should this go in xfs_parent.c ? > +{ > + > + struct xfs_attrlist *alist; > + struct xfs_attrlist_ent *aent; > + struct xfs_parent_ptr *xpp; > + struct xfs_parent_name_rec *xpnr; > + char *namebuf; > + unsigned int namebuf_size; > + int name_len; > + int error = 0; > + unsigned int ioc_flags = XFS_IOC_ATTR_PARENT; > + unsigned int flags = XFS_ATTR_PARENT; > + int i; > + struct xfs_attr_list_context context; > + struct xfs_da_args args; > + > + /* Allocate a buffer to store the attribute names */ > + namebuf_size = sizeof(struct xfs_attrlist) + > + (ppi->pi_ptrs_size) * sizeof(struct xfs_attrlist_ent); > + namebuf = kvzalloc(namebuf_size, GFP_KERNEL); > + if (!namebuf) > + return -ENOMEM; > + > + memset(&context, 0, sizeof(struct xfs_attr_list_context)); > + error = xfs_ioc_attr_list_context_init(ip, namebuf, namebuf_size, > + ioc_flags, &context); > + > + /* Copy the cursor provided by caller */ > + memcpy(&context.cursor, &ppi->pi_cursor, > + sizeof(struct xfs_attrlist_cursor)); > + > + if (error) > + goto out_kfree; > + > + xfs_ilock(ip, XFS_ILOCK_EXCL); > + > + error = xfs_attr_list_ilocked(&context); > + if (error) > + goto out_kfree; > + > + alist = (struct xfs_attrlist *)namebuf; > + for (i = 0; i < alist->al_count; i++) { > + xpp = XFS_PPINFO_TO_PP(ppi, i); > + memset(xpp, 0, sizeof(struct xfs_parent_ptr)); > + aent = (struct xfs_attrlist_ent *) > + &namebuf[alist->al_offset[i]]; > + xpnr = (struct xfs_parent_name_rec *)(aent->a_name); > + > + if (aent->a_valuelen > XFS_PPTR_MAXNAMELEN) { > + error = -ERANGE; > + goto out_kfree; > + } > + name_len = aent->a_valuelen; > + > + memset(&args, 0, sizeof(args)); > + args.geo = ip->i_mount->m_attr_geo; > + args.whichfork = XFS_ATTR_FORK; > + args.dp = ip; > + args.name = (char *)xpnr; > + args.namelen = sizeof(struct xfs_parent_name_rec); > + args.attr_filter = flags; > + args.hashval = xfs_da_hashname(args.name, args.namelen); > + args.value = (unsigned char *)(xpp->xpp_name); > + args.valuelen = name_len; > + args.op_flags = XFS_DA_OP_OKNOENT; You might want to convert this to a C99 named initialization inside the loop body. Otherwise looks ok. --D > + > + error = xfs_attr_get_ilocked(&args); > + error = (error == -EEXIST ? 0 : error); > + if (error) > + goto out_kfree; > + > + xpp->xpp_namelen = name_len; > + xfs_init_parent_ptr(xpp, xpnr); > + } > + ppi->pi_ptrs_used = alist->al_count; > + if (!alist->al_more) > + ppi->pi_flags |= XFS_PPTR_OFLAG_DONE; > + > + /* Update the caller with the current cursor position */ > + memcpy(&ppi->pi_cursor, &context.cursor, > + sizeof(struct xfs_attrlist_cursor)); > + > +out_kfree: > + xfs_iunlock(ip, XFS_ILOCK_EXCL); > + kmem_free(namebuf); > + > + return error; > +} > + > diff --git a/fs/xfs/xfs_parent_utils.h b/fs/xfs/xfs_parent_utils.h > new file mode 100644 > index 000000000000..0e952b2ebd4a > --- /dev/null > +++ b/fs/xfs/xfs_parent_utils.h > @@ -0,0 +1,22 @@ > +/* > + * Copyright (c) 2017 Oracle, Inc. > + * All Rights Reserved. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it would be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write the Free Software Foundation Inc. > + */ > +#ifndef __XFS_PARENT_UTILS_H__ > +#define __XFS_PARENT_UTILS_H__ > + > +int xfs_attr_get_parent_pointer(struct xfs_inode *ip, > + struct xfs_pptr_info *ppi); > +#endif /* __XFS_PARENT_UTILS_H__ */ > -- > 2.25.1 >
On Wed, 2022-06-29 at 11:52 -0700, Darrick J. Wong wrote: > On Sat, Jun 11, 2022 at 02:42:00AM -0700, Allison Henderson wrote: > > This patch adds a new file ioctl to retrieve the parent pointer of > > a > > given inode > > > > Signed-off-by: Allison Henderson <allison.henderson@oracle.com> > > --- > > fs/xfs/Makefile | 1 + > > fs/xfs/libxfs/xfs_fs.h | 46 +++++++++++++ > > fs/xfs/libxfs/xfs_parent.c | 10 +++ > > fs/xfs/libxfs/xfs_parent.h | 2 + > > fs/xfs/xfs_ioctl.c | 90 ++++++++++++++++++++++++- > > fs/xfs/xfs_ondisk.h | 4 ++ > > fs/xfs/xfs_parent_utils.c | 133 > > +++++++++++++++++++++++++++++++++++++ > > fs/xfs/xfs_parent_utils.h | 22 ++++++ > > 8 files changed, 306 insertions(+), 2 deletions(-) > > > > diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile > > index fc717dc3470c..da86f6231f2e 100644 > > --- a/fs/xfs/Makefile > > +++ b/fs/xfs/Makefile > > @@ -86,6 +86,7 @@ xfs-y += xfs_aops.o \ > > xfs_mount.o \ > > xfs_mru_cache.o \ > > xfs_pwork.o \ > > + xfs_parent_utils.o \ > > xfs_reflink.o \ > > xfs_stats.o \ > > xfs_super.o \ > > diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h > > index b0b4d7a3aa15..e6c8873cd234 100644 > > --- a/fs/xfs/libxfs/xfs_fs.h > > +++ b/fs/xfs/libxfs/xfs_fs.h > > @@ -574,6 +574,7 @@ typedef struct xfs_fsop_handlereq { > > #define XFS_IOC_ATTR_SECURE 0x0008 /* use attrs in > > security namespace */ > > #define XFS_IOC_ATTR_CREATE 0x0010 /* fail if attr > > already exists */ > > #define XFS_IOC_ATTR_REPLACE 0x0020 /* fail if attr > > does not exist */ > > +#define XFS_IOC_ATTR_PARENT 0x0040 /* use attrs in parent > > namespace */ > > > > typedef struct xfs_attrlist_cursor { > > __u32 opaque[4]; > > @@ -752,6 +753,50 @@ struct xfs_scrub_metadata { > > XFS_SCRUB_OFLAG_NO_REPAIR_NEEDED) > > #define XFS_SCRUB_FLAGS_ALL (XFS_SCRUB_FLAGS_IN | > > XFS_SCRUB_FLAGS_OUT) > > > > +#define XFS_PPTR_MAXNAMELEN 256 > > + > > +/* return parents of the handle, not the open fd */ > > +#define XFS_PPTR_IFLAG_HANDLE (1U << 0) > > + > > +/* target was the root directory */ > > +#define XFS_PPTR_OFLAG_ROOT (1U << 1) > > + > > +/* Cursor is done iterating pptrs */ > > +#define XFS_PPTR_OFLAG_DONE (1U << 2) > > + > > +/* Get an inode parent pointer through ioctl */ > > +struct xfs_parent_ptr { > > + __u64 xpp_ino; /* Inode */ > > + __u32 xpp_gen; /* Inode > > generation */ > > + __u32 xpp_diroffset; /* > > Directory offset */ > > + __u32 xpp_namelen; /* File > > name length */ > > + __u32 xpp_pad; > > + __u8 xpp_name[XFS_PPTR_MAXNAMELEN]; /* File > > name */ > > +}; > > + > > +/* Iterate through an inodes parent pointers */ > > +struct xfs_pptr_info { > > + struct xfs_handle pi_handle; > > + struct xfs_attrlist_cursor pi_cursor; > > + __u32 pi_flags; > > + __u32 pi_reserved; > > + __u32 pi_ptrs_size; > > + __u32 pi_ptrs_used; > > + __u64 pi_reserved2[6]; > > + > > + /* > > + * An array of struct xfs_parent_ptr follows the header > > + * information. Use XFS_PPINFO_TO_PP() to access the > > + * parent pointer array entries. > > + */ > > struct xfs_parent_ptr pi_parents[]; > > Unless you want to conserve space in the userspace buffer by making > the > size of xfs_parent_ptr itself variable? Userspace would have to walk > the entire buffer by hand like it does for listxattr, but it saves a > fair amount of space. Oh i see, I can take a look at it. Honestly I think the only thing in user space that's interested in parent pointers might be the test case, so I'm not too worried about it atm. But let me see if I can cut down the buffer usage a bit. > > > +}; > > + > > +#define XFS_PPTR_INFO_SIZEOF(nr_ptrs) sizeof (struct > > xfs_pptr_info) + \ > > + nr_ptrs * sizeof(struct > > xfs_parent_ptr) > > + > > +#define XFS_PPINFO_TO_PP(info, idx) \ > > + (&(((struct xfs_parent_ptr *)((char *)(info) + > > sizeof(*(info))))[(idx)])) > > Turn these into static inline functions so that client programs get > some > proper typechecking by the C compiler. > Sure, will do > > + > > /* > > * ioctl limits > > */ > > @@ -797,6 +842,7 @@ struct xfs_scrub_metadata { > > /* XFS_IOC_GETFSMAP ------ hoisted 59 */ > > #define XFS_IOC_SCRUB_METADATA _IOWR('X', 60, struct > > xfs_scrub_metadata) > > #define XFS_IOC_AG_GEOMETRY _IOWR('X', 61, struct > > xfs_ag_geometry) > > +#define XFS_IOC_GETPPOINTER _IOR ('X', 62, struct > > xfs_parent_ptr) > > > > /* > > * ioctl commands that replace IRIX syssgi()'s > > diff --git a/fs/xfs/libxfs/xfs_parent.c > > b/fs/xfs/libxfs/xfs_parent.c > > index cb546652bde9..a5b99f30bc63 100644 > > --- a/fs/xfs/libxfs/xfs_parent.c > > +++ b/fs/xfs/libxfs/xfs_parent.c > > @@ -33,6 +33,16 @@ > > #include "xfs_attr_sf.h" > > #include "xfs_bmap.h" > > > > +/* Initializes a xfs_parent_ptr from an xfs_parent_name_rec */ > > +void > > +xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, > > + struct xfs_parent_name_rec *rec) > > Indenting... > Will fix > > +{ > > + xpp->xpp_ino = be64_to_cpu(rec->p_ino); > > + xpp->xpp_gen = be32_to_cpu(rec->p_gen); > > + xpp->xpp_diroffset = be32_to_cpu(rec->p_diroffset); > > +} > > + > > /* > > * Parent pointer attribute handling. > > * > > diff --git a/fs/xfs/libxfs/xfs_parent.h > > b/fs/xfs/libxfs/xfs_parent.h > > index 10dc576ce693..fa50ada0d6a9 100644 > > --- a/fs/xfs/libxfs/xfs_parent.h > > +++ b/fs/xfs/libxfs/xfs_parent.h > > @@ -28,4 +28,6 @@ void xfs_init_parent_name_rec(struct > > xfs_parent_name_rec *rec, > > uint32_t p_diroffset); > > void xfs_init_parent_name_irec(struct xfs_parent_name_irec *irec, > > struct xfs_parent_name_rec *rec); > > +void xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, > > + struct xfs_parent_name_rec *rec); > > #endif /* __XFS_PARENT_H__ */ > > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > > index e1612e99e0c5..4cd1de3e9d0b 100644 > > --- a/fs/xfs/xfs_ioctl.c > > +++ b/fs/xfs/xfs_ioctl.c > > @@ -37,6 +37,7 @@ > > #include "xfs_health.h" > > #include "xfs_reflink.h" > > #include "xfs_ioctl.h" > > +#include "xfs_parent_utils.h" > > #include "xfs_xattr.h" > > > > #include <linux/mount.h> > > @@ -355,6 +356,8 @@ xfs_attr_filter( > > return XFS_ATTR_ROOT; > > if (ioc_flags & XFS_IOC_ATTR_SECURE) > > return XFS_ATTR_SECURE; > > + if (ioc_flags & XFS_IOC_ATTR_PARENT) > > + return XFS_ATTR_PARENT; > > return 0; > > } > > > > @@ -422,7 +425,8 @@ xfs_ioc_attr_list( > > /* > > * Reject flags, only allow namespaces. > > */ > > - if (flags & ~(XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE)) > > + if (flags & ~(XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE | > > + XFS_IOC_ATTR_PARENT)) > > return -EINVAL; > > if (flags == (XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE)) > > return -EINVAL; > > @@ -1672,6 +1676,87 @@ xfs_ioc_scrub_metadata( > > return 0; > > } > > > > +/* > > + * IOCTL routine to get the parent pointers of an inode and return > > it to user > > + * space. Caller must pass a buffer space containing a struct > > xfs_pptr_info, > > + * followed by a region large enough to contain an array of struct > > + * xfs_parent_ptr of a size specified in pi_ptrs_size. If the > > inode contains > > + * more parent pointers than can fit in the buffer space, caller > > may re-call > > + * the function using the returned pi_cursor to resume > > iteration. The > > + * number of xfs_parent_ptr returned will be stored in > > pi_ptrs_used. > > + * > > + * Returns 0 on success or non-zero on failure > > + */ > > +STATIC int > > +xfs_ioc_get_parent_pointer( > > + struct file *filp, > > + void __user *arg) > > +{ > > + struct xfs_pptr_info *ppi = NULL; > > + int error = 0; > > + struct xfs_inode *ip = XFS_I(file_inode(filp)); > > + struct xfs_mount *mp = ip->i_mount; > > + > > + if (!capable(CAP_SYS_ADMIN)) > > + return -EPERM; > > + > > + /* Allocate an xfs_pptr_info to put the user data */ > > + ppi = kmem_alloc(sizeof(struct xfs_pptr_info), 0); > > + if (!ppi) > > + return -ENOMEM; > > + > > + /* Copy the data from the user */ > > + error = copy_from_user(ppi, arg, sizeof(struct xfs_pptr_info)); > > + if (error) > > + goto out; > > + > > + /* Check size of buffer requested by user */ > > + if (XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size) > > > XFS_XATTR_LIST_MAX) { > > + error = -ENOMEM; > > + goto out; > > + } > > + > > + /* > > + * Now that we know how big the trailing buffer is, expand > > + * our kernel xfs_pptr_info to be the same size > > + */ > > + ppi = krealloc(ppi, XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size), > > + GFP_NOFS | __GFP_NOFAIL); > > + if (!ppi) > > + return -ENOMEM; > > + > > + if (ppi->pi_flags != 0 && ppi->pi_flags != > > XFS_PPTR_IFLAG_HANDLE) { > > Flags validation should come before the big memory allocation. > Alrighty, will scoot up > > + error = -EINVAL; > > + goto out; > > + } > > + > > + if (ppi->pi_flags == XFS_PPTR_IFLAG_HANDLE) { > > + error = xfs_iget(mp, NULL, ppi- > > >pi_handle.ha_fid.fid_ino, > > + 0, 0, &ip); > > + if (error) > > + goto out; > > This ought to be checking the generation number in the file handle. Oh I see, sure I will add that in > > > + } > > + > > + if (ip->i_ino == mp->m_sb.sb_rootino) > > + ppi->pi_flags |= XFS_PPTR_OFLAG_ROOT; > > + > > + /* Get the parent pointers */ > > + error = xfs_attr_get_parent_pointer(ip, ppi); > > + > > + if (error) > > + goto out; > > + > > + /* Copy the parent pointers back to the user */ > > + error = copy_to_user(arg, ppi, > > + XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size)); > > + if (error) > > + goto out; > > + > > +out: > > + kmem_free(ppi); > > + return error; > > +} > > + > > int > > xfs_ioc_swapext( > > xfs_swapext_t *sxp) > > @@ -1961,7 +2046,8 @@ xfs_file_ioctl( > > > > case XFS_IOC_FSGETXATTRA: > > return xfs_ioc_fsgetxattra(ip, arg); > > - > > + case XFS_IOC_GETPPOINTER: > > + return xfs_ioc_get_parent_pointer(filp, arg); > > case XFS_IOC_GETBMAP: > > case XFS_IOC_GETBMAPA: > > case XFS_IOC_GETBMAPX: > > diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h > > index 758702b9495f..765eb514a917 100644 > > --- a/fs/xfs/xfs_ondisk.h > > +++ b/fs/xfs/xfs_ondisk.h > > @@ -135,6 +135,10 @@ xfs_check_ondisk_structs(void) > > XFS_CHECK_STRUCT_SIZE(struct xfs_attri_log_format, 40); > > XFS_CHECK_STRUCT_SIZE(struct xfs_attrd_log_format, 16); > > > > + /* parent pointer ioctls */ > > + XFS_CHECK_STRUCT_SIZE(struct xfs_parent_ptr, 280); > > + XFS_CHECK_STRUCT_SIZE(struct xfs_pptr_info, 104); > > + > > /* > > * The v5 superblock format extended several v4 header > > structures with > > * additional data. While new fields are only accessible on v5 > > diff --git a/fs/xfs/xfs_parent_utils.c b/fs/xfs/xfs_parent_utils.c > > new file mode 100644 > > index 000000000000..9880718395c6 > > --- /dev/null > > +++ b/fs/xfs/xfs_parent_utils.c > > @@ -0,0 +1,133 @@ > > +/* > > + * Copyright (c) 2015 Red Hat, Inc. > > + * All rights reserved. > > + * > > + * This program is free software; you can redistribute it and/or > > + * modify it under the terms of the GNU General Public License as > > + * published by the Free Software Foundation. > > + * > > + * This program is distributed in the hope that it would be > > useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + * > > + * You should have received a copy of the GNU General Public > > License > > + * along with this program; if not, write the Free Software > > Foundation > > + */ > > +#include "xfs.h" > > +#include "xfs_fs.h" > > +#include "xfs_format.h" > > +#include "xfs_log_format.h" > > +#include "xfs_shared.h" > > +#include "xfs_trans_resv.h" > > +#include "xfs_mount.h" > > +#include "xfs_bmap_btree.h" > > +#include "xfs_inode.h" > > +#include "xfs_error.h" > > +#include "xfs_trace.h" > > +#include "xfs_trans.h" > > +#include "xfs_da_format.h" > > +#include "xfs_da_btree.h" > > +#include "xfs_attr.h" > > +#include "xfs_ioctl.h" > > +#include "xfs_parent.h" > > +#include "xfs_da_btree.h" > > + > > +/* > > + * Get the parent pointers for a given inode > > + * > > + * Returns 0 on success and non zero on error > > + */ > > +int > > +xfs_attr_get_parent_pointer(struct xfs_inode *ip, > > + struct xfs_pptr_info *ppi) > > + > > Indenting. Also, should this go in xfs_parent.c ? > Will fix indenting. I think the reason I put it here was to avoid unnecessary porting to libxfs. Since parent.c is in libxfs and utils is not. > > +{ > > + > > + struct xfs_attrlist *alist; > > + struct xfs_attrlist_ent *aent; > > + struct xfs_parent_ptr *xpp; > > + struct xfs_parent_name_rec *xpnr; > > + char *namebuf; > > + unsigned int namebuf_size; > > + int name_len; > > + int error = 0; > > + unsigned int ioc_flags = > > XFS_IOC_ATTR_PARENT; > > + unsigned int flags = XFS_ATTR_PARENT; > > + int i; > > + struct xfs_attr_list_context context; > > + struct xfs_da_args args; > > + > > + /* Allocate a buffer to store the attribute names */ > > + namebuf_size = sizeof(struct xfs_attrlist) + > > + (ppi->pi_ptrs_size) * sizeof(struct > > xfs_attrlist_ent); > > + namebuf = kvzalloc(namebuf_size, GFP_KERNEL); > > + if (!namebuf) > > + return -ENOMEM; > > + > > + memset(&context, 0, sizeof(struct xfs_attr_list_context)); > > + error = xfs_ioc_attr_list_context_init(ip, namebuf, > > namebuf_size, > > + ioc_flags, &context); > > + > > + /* Copy the cursor provided by caller */ > > + memcpy(&context.cursor, &ppi->pi_cursor, > > + sizeof(struct xfs_attrlist_cursor)); > > + > > + if (error) > > + goto out_kfree; > > + > > + xfs_ilock(ip, XFS_ILOCK_EXCL); > > + > > + error = xfs_attr_list_ilocked(&context); > > + if (error) > > + goto out_kfree; > > + > > + alist = (struct xfs_attrlist *)namebuf; > > + for (i = 0; i < alist->al_count; i++) { > > + xpp = XFS_PPINFO_TO_PP(ppi, i); > > + memset(xpp, 0, sizeof(struct xfs_parent_ptr)); > > + aent = (struct xfs_attrlist_ent *) > > + &namebuf[alist->al_offset[i]]; > > + xpnr = (struct xfs_parent_name_rec *)(aent->a_name); > > + > > + if (aent->a_valuelen > XFS_PPTR_MAXNAMELEN) { > > + error = -ERANGE; > > + goto out_kfree; > > + } > > + name_len = aent->a_valuelen; > > + > > + memset(&args, 0, sizeof(args)); > > + args.geo = ip->i_mount->m_attr_geo; > > + args.whichfork = XFS_ATTR_FORK; > > + args.dp = ip; > > + args.name = (char *)xpnr; > > + args.namelen = sizeof(struct xfs_parent_name_rec); > > + args.attr_filter = flags; > > + args.hashval = xfs_da_hashname(args.name, > > args.namelen); > > + args.value = (unsigned char *)(xpp->xpp_name); > > + args.valuelen = name_len; > > + args.op_flags = XFS_DA_OP_OKNOENT; > > You might want to convert this to a C99 named initialization inside > the > loop body. Ok, will do. > > Otherwise looks ok. > Great! Thanks! Allison > --D > > > + > > + error = xfs_attr_get_ilocked(&args); > > + error = (error == -EEXIST ? 0 : error); > > + if (error) > > + goto out_kfree; > > + > > + xpp->xpp_namelen = name_len; > > + xfs_init_parent_ptr(xpp, xpnr); > > + } > > + ppi->pi_ptrs_used = alist->al_count; > > + if (!alist->al_more) > > + ppi->pi_flags |= XFS_PPTR_OFLAG_DONE; > > + > > + /* Update the caller with the current cursor position */ > > + memcpy(&ppi->pi_cursor, &context.cursor, > > + sizeof(struct xfs_attrlist_cursor)); > > + > > +out_kfree: > > + xfs_iunlock(ip, XFS_ILOCK_EXCL); > > + kmem_free(namebuf); > > + > > + return error; > > +} > > + > > diff --git a/fs/xfs/xfs_parent_utils.h b/fs/xfs/xfs_parent_utils.h > > new file mode 100644 > > index 000000000000..0e952b2ebd4a > > --- /dev/null > > +++ b/fs/xfs/xfs_parent_utils.h > > @@ -0,0 +1,22 @@ > > +/* > > + * Copyright (c) 2017 Oracle, Inc. > > + * All Rights Reserved. > > + * > > + * This program is free software; you can redistribute it and/or > > + * modify it under the terms of the GNU General Public License as > > + * published by the Free Software Foundation. > > + * > > + * This program is distributed in the hope that it would be > > useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + * > > + * You should have received a copy of the GNU General Public > > License > > + * along with this program; if not, write the Free Software > > Foundation Inc. > > + */ > > +#ifndef __XFS_PARENT_UTILS_H__ > > +#define __XFS_PARENT_UTILS_H__ > > + > > +int xfs_attr_get_parent_pointer(struct xfs_inode *ip, > > + struct xfs_pptr_info *ppi); > > +#endif /* __XFS_PARENT_UTILS_H__ */ > > -- > > 2.25.1 > >
diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index fc717dc3470c..da86f6231f2e 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -86,6 +86,7 @@ xfs-y += xfs_aops.o \ xfs_mount.o \ xfs_mru_cache.o \ xfs_pwork.o \ + xfs_parent_utils.o \ xfs_reflink.o \ xfs_stats.o \ xfs_super.o \ diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index b0b4d7a3aa15..e6c8873cd234 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -574,6 +574,7 @@ typedef struct xfs_fsop_handlereq { #define XFS_IOC_ATTR_SECURE 0x0008 /* use attrs in security namespace */ #define XFS_IOC_ATTR_CREATE 0x0010 /* fail if attr already exists */ #define XFS_IOC_ATTR_REPLACE 0x0020 /* fail if attr does not exist */ +#define XFS_IOC_ATTR_PARENT 0x0040 /* use attrs in parent namespace */ typedef struct xfs_attrlist_cursor { __u32 opaque[4]; @@ -752,6 +753,50 @@ struct xfs_scrub_metadata { XFS_SCRUB_OFLAG_NO_REPAIR_NEEDED) #define XFS_SCRUB_FLAGS_ALL (XFS_SCRUB_FLAGS_IN | XFS_SCRUB_FLAGS_OUT) +#define XFS_PPTR_MAXNAMELEN 256 + +/* return parents of the handle, not the open fd */ +#define XFS_PPTR_IFLAG_HANDLE (1U << 0) + +/* target was the root directory */ +#define XFS_PPTR_OFLAG_ROOT (1U << 1) + +/* Cursor is done iterating pptrs */ +#define XFS_PPTR_OFLAG_DONE (1U << 2) + +/* Get an inode parent pointer through ioctl */ +struct xfs_parent_ptr { + __u64 xpp_ino; /* Inode */ + __u32 xpp_gen; /* Inode generation */ + __u32 xpp_diroffset; /* Directory offset */ + __u32 xpp_namelen; /* File name length */ + __u32 xpp_pad; + __u8 xpp_name[XFS_PPTR_MAXNAMELEN]; /* File name */ +}; + +/* Iterate through an inodes parent pointers */ +struct xfs_pptr_info { + struct xfs_handle pi_handle; + struct xfs_attrlist_cursor pi_cursor; + __u32 pi_flags; + __u32 pi_reserved; + __u32 pi_ptrs_size; + __u32 pi_ptrs_used; + __u64 pi_reserved2[6]; + + /* + * An array of struct xfs_parent_ptr follows the header + * information. Use XFS_PPINFO_TO_PP() to access the + * parent pointer array entries. + */ +}; + +#define XFS_PPTR_INFO_SIZEOF(nr_ptrs) sizeof (struct xfs_pptr_info) + \ + nr_ptrs * sizeof(struct xfs_parent_ptr) + +#define XFS_PPINFO_TO_PP(info, idx) \ + (&(((struct xfs_parent_ptr *)((char *)(info) + sizeof(*(info))))[(idx)])) + /* * ioctl limits */ @@ -797,6 +842,7 @@ struct xfs_scrub_metadata { /* XFS_IOC_GETFSMAP ------ hoisted 59 */ #define XFS_IOC_SCRUB_METADATA _IOWR('X', 60, struct xfs_scrub_metadata) #define XFS_IOC_AG_GEOMETRY _IOWR('X', 61, struct xfs_ag_geometry) +#define XFS_IOC_GETPPOINTER _IOR ('X', 62, struct xfs_parent_ptr) /* * ioctl commands that replace IRIX syssgi()'s diff --git a/fs/xfs/libxfs/xfs_parent.c b/fs/xfs/libxfs/xfs_parent.c index cb546652bde9..a5b99f30bc63 100644 --- a/fs/xfs/libxfs/xfs_parent.c +++ b/fs/xfs/libxfs/xfs_parent.c @@ -33,6 +33,16 @@ #include "xfs_attr_sf.h" #include "xfs_bmap.h" +/* Initializes a xfs_parent_ptr from an xfs_parent_name_rec */ +void +xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, + struct xfs_parent_name_rec *rec) +{ + xpp->xpp_ino = be64_to_cpu(rec->p_ino); + xpp->xpp_gen = be32_to_cpu(rec->p_gen); + xpp->xpp_diroffset = be32_to_cpu(rec->p_diroffset); +} + /* * Parent pointer attribute handling. * diff --git a/fs/xfs/libxfs/xfs_parent.h b/fs/xfs/libxfs/xfs_parent.h index 10dc576ce693..fa50ada0d6a9 100644 --- a/fs/xfs/libxfs/xfs_parent.h +++ b/fs/xfs/libxfs/xfs_parent.h @@ -28,4 +28,6 @@ void xfs_init_parent_name_rec(struct xfs_parent_name_rec *rec, uint32_t p_diroffset); void xfs_init_parent_name_irec(struct xfs_parent_name_irec *irec, struct xfs_parent_name_rec *rec); +void xfs_init_parent_ptr(struct xfs_parent_ptr *xpp, + struct xfs_parent_name_rec *rec); #endif /* __XFS_PARENT_H__ */ diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index e1612e99e0c5..4cd1de3e9d0b 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -37,6 +37,7 @@ #include "xfs_health.h" #include "xfs_reflink.h" #include "xfs_ioctl.h" +#include "xfs_parent_utils.h" #include "xfs_xattr.h" #include <linux/mount.h> @@ -355,6 +356,8 @@ xfs_attr_filter( return XFS_ATTR_ROOT; if (ioc_flags & XFS_IOC_ATTR_SECURE) return XFS_ATTR_SECURE; + if (ioc_flags & XFS_IOC_ATTR_PARENT) + return XFS_ATTR_PARENT; return 0; } @@ -422,7 +425,8 @@ xfs_ioc_attr_list( /* * Reject flags, only allow namespaces. */ - if (flags & ~(XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE)) + if (flags & ~(XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE | + XFS_IOC_ATTR_PARENT)) return -EINVAL; if (flags == (XFS_IOC_ATTR_ROOT | XFS_IOC_ATTR_SECURE)) return -EINVAL; @@ -1672,6 +1676,87 @@ xfs_ioc_scrub_metadata( return 0; } +/* + * IOCTL routine to get the parent pointers of an inode and return it to user + * space. Caller must pass a buffer space containing a struct xfs_pptr_info, + * followed by a region large enough to contain an array of struct + * xfs_parent_ptr of a size specified in pi_ptrs_size. If the inode contains + * more parent pointers than can fit in the buffer space, caller may re-call + * the function using the returned pi_cursor to resume iteration. The + * number of xfs_parent_ptr returned will be stored in pi_ptrs_used. + * + * Returns 0 on success or non-zero on failure + */ +STATIC int +xfs_ioc_get_parent_pointer( + struct file *filp, + void __user *arg) +{ + struct xfs_pptr_info *ppi = NULL; + int error = 0; + struct xfs_inode *ip = XFS_I(file_inode(filp)); + struct xfs_mount *mp = ip->i_mount; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* Allocate an xfs_pptr_info to put the user data */ + ppi = kmem_alloc(sizeof(struct xfs_pptr_info), 0); + if (!ppi) + return -ENOMEM; + + /* Copy the data from the user */ + error = copy_from_user(ppi, arg, sizeof(struct xfs_pptr_info)); + if (error) + goto out; + + /* Check size of buffer requested by user */ + if (XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size) > XFS_XATTR_LIST_MAX) { + error = -ENOMEM; + goto out; + } + + /* + * Now that we know how big the trailing buffer is, expand + * our kernel xfs_pptr_info to be the same size + */ + ppi = krealloc(ppi, XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size), + GFP_NOFS | __GFP_NOFAIL); + if (!ppi) + return -ENOMEM; + + if (ppi->pi_flags != 0 && ppi->pi_flags != XFS_PPTR_IFLAG_HANDLE) { + error = -EINVAL; + goto out; + } + + if (ppi->pi_flags == XFS_PPTR_IFLAG_HANDLE) { + error = xfs_iget(mp, NULL, ppi->pi_handle.ha_fid.fid_ino, + 0, 0, &ip); + if (error) + goto out; + } + + if (ip->i_ino == mp->m_sb.sb_rootino) + ppi->pi_flags |= XFS_PPTR_OFLAG_ROOT; + + /* Get the parent pointers */ + error = xfs_attr_get_parent_pointer(ip, ppi); + + if (error) + goto out; + + /* Copy the parent pointers back to the user */ + error = copy_to_user(arg, ppi, + XFS_PPTR_INFO_SIZEOF(ppi->pi_ptrs_size)); + if (error) + goto out; + +out: + kmem_free(ppi); + return error; +} + int xfs_ioc_swapext( xfs_swapext_t *sxp) @@ -1961,7 +2046,8 @@ xfs_file_ioctl( case XFS_IOC_FSGETXATTRA: return xfs_ioc_fsgetxattra(ip, arg); - + case XFS_IOC_GETPPOINTER: + return xfs_ioc_get_parent_pointer(filp, arg); case XFS_IOC_GETBMAP: case XFS_IOC_GETBMAPA: case XFS_IOC_GETBMAPX: diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h index 758702b9495f..765eb514a917 100644 --- a/fs/xfs/xfs_ondisk.h +++ b/fs/xfs/xfs_ondisk.h @@ -135,6 +135,10 @@ xfs_check_ondisk_structs(void) XFS_CHECK_STRUCT_SIZE(struct xfs_attri_log_format, 40); XFS_CHECK_STRUCT_SIZE(struct xfs_attrd_log_format, 16); + /* parent pointer ioctls */ + XFS_CHECK_STRUCT_SIZE(struct xfs_parent_ptr, 280); + XFS_CHECK_STRUCT_SIZE(struct xfs_pptr_info, 104); + /* * The v5 superblock format extended several v4 header structures with * additional data. While new fields are only accessible on v5 diff --git a/fs/xfs/xfs_parent_utils.c b/fs/xfs/xfs_parent_utils.c new file mode 100644 index 000000000000..9880718395c6 --- /dev/null +++ b/fs/xfs/xfs_parent_utils.c @@ -0,0 +1,133 @@ +/* + * Copyright (c) 2015 Red Hat, Inc. + * All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_shared.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_bmap_btree.h" +#include "xfs_inode.h" +#include "xfs_error.h" +#include "xfs_trace.h" +#include "xfs_trans.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_attr.h" +#include "xfs_ioctl.h" +#include "xfs_parent.h" +#include "xfs_da_btree.h" + +/* + * Get the parent pointers for a given inode + * + * Returns 0 on success and non zero on error + */ +int +xfs_attr_get_parent_pointer(struct xfs_inode *ip, + struct xfs_pptr_info *ppi) + +{ + + struct xfs_attrlist *alist; + struct xfs_attrlist_ent *aent; + struct xfs_parent_ptr *xpp; + struct xfs_parent_name_rec *xpnr; + char *namebuf; + unsigned int namebuf_size; + int name_len; + int error = 0; + unsigned int ioc_flags = XFS_IOC_ATTR_PARENT; + unsigned int flags = XFS_ATTR_PARENT; + int i; + struct xfs_attr_list_context context; + struct xfs_da_args args; + + /* Allocate a buffer to store the attribute names */ + namebuf_size = sizeof(struct xfs_attrlist) + + (ppi->pi_ptrs_size) * sizeof(struct xfs_attrlist_ent); + namebuf = kvzalloc(namebuf_size, GFP_KERNEL); + if (!namebuf) + return -ENOMEM; + + memset(&context, 0, sizeof(struct xfs_attr_list_context)); + error = xfs_ioc_attr_list_context_init(ip, namebuf, namebuf_size, + ioc_flags, &context); + + /* Copy the cursor provided by caller */ + memcpy(&context.cursor, &ppi->pi_cursor, + sizeof(struct xfs_attrlist_cursor)); + + if (error) + goto out_kfree; + + xfs_ilock(ip, XFS_ILOCK_EXCL); + + error = xfs_attr_list_ilocked(&context); + if (error) + goto out_kfree; + + alist = (struct xfs_attrlist *)namebuf; + for (i = 0; i < alist->al_count; i++) { + xpp = XFS_PPINFO_TO_PP(ppi, i); + memset(xpp, 0, sizeof(struct xfs_parent_ptr)); + aent = (struct xfs_attrlist_ent *) + &namebuf[alist->al_offset[i]]; + xpnr = (struct xfs_parent_name_rec *)(aent->a_name); + + if (aent->a_valuelen > XFS_PPTR_MAXNAMELEN) { + error = -ERANGE; + goto out_kfree; + } + name_len = aent->a_valuelen; + + memset(&args, 0, sizeof(args)); + args.geo = ip->i_mount->m_attr_geo; + args.whichfork = XFS_ATTR_FORK; + args.dp = ip; + args.name = (char *)xpnr; + args.namelen = sizeof(struct xfs_parent_name_rec); + args.attr_filter = flags; + args.hashval = xfs_da_hashname(args.name, args.namelen); + args.value = (unsigned char *)(xpp->xpp_name); + args.valuelen = name_len; + args.op_flags = XFS_DA_OP_OKNOENT; + + error = xfs_attr_get_ilocked(&args); + error = (error == -EEXIST ? 0 : error); + if (error) + goto out_kfree; + + xpp->xpp_namelen = name_len; + xfs_init_parent_ptr(xpp, xpnr); + } + ppi->pi_ptrs_used = alist->al_count; + if (!alist->al_more) + ppi->pi_flags |= XFS_PPTR_OFLAG_DONE; + + /* Update the caller with the current cursor position */ + memcpy(&ppi->pi_cursor, &context.cursor, + sizeof(struct xfs_attrlist_cursor)); + +out_kfree: + xfs_iunlock(ip, XFS_ILOCK_EXCL); + kmem_free(namebuf); + + return error; +} + diff --git a/fs/xfs/xfs_parent_utils.h b/fs/xfs/xfs_parent_utils.h new file mode 100644 index 000000000000..0e952b2ebd4a --- /dev/null +++ b/fs/xfs/xfs_parent_utils.h @@ -0,0 +1,22 @@ +/* + * Copyright (c) 2017 Oracle, Inc. + * All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation Inc. + */ +#ifndef __XFS_PARENT_UTILS_H__ +#define __XFS_PARENT_UTILS_H__ + +int xfs_attr_get_parent_pointer(struct xfs_inode *ip, + struct xfs_pptr_info *ppi); +#endif /* __XFS_PARENT_UTILS_H__ */
This patch adds a new file ioctl to retrieve the parent pointer of a given inode Signed-off-by: Allison Henderson <allison.henderson@oracle.com> --- fs/xfs/Makefile | 1 + fs/xfs/libxfs/xfs_fs.h | 46 +++++++++++++ fs/xfs/libxfs/xfs_parent.c | 10 +++ fs/xfs/libxfs/xfs_parent.h | 2 + fs/xfs/xfs_ioctl.c | 90 ++++++++++++++++++++++++- fs/xfs/xfs_ondisk.h | 4 ++ fs/xfs/xfs_parent_utils.c | 133 +++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_parent_utils.h | 22 ++++++ 8 files changed, 306 insertions(+), 2 deletions(-)