--- /dev/null
+/*
+ * Copyright (C) International Business Machines Corp., 2000-2004
+ * Copyright (C) Christoph Hellwig, 2002
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will 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 to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/capability.h>
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+#include <linux/slab.h>
+#include <linux/quotaops.h>
+#include <linux/security.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_debug.h"
+#include "jfs_dinode.h"
+#include "jfs_extent.h"
+#include "jfs_metapage.h"
+#include "jfs_xattr.h"
+#include "jfs_acl.h"
+
+/*
+ * jfs_xattr.c: extended attribute service
+ *
+ * Overall design --
+ *
+ * Format:
+ *
+ * Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit
+ * value) and a variable (0 or more) number of extended attribute
+ * entries. Each extended attribute entry (jfs_ea) is a <name,value> double
+ * where <name> is constructed from a null-terminated ascii string
+ * (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data
+ * (1 ... 65535 bytes). The in-memory format is
+ *
+ * 0 1 2 4 4 + namelen + 1
+ * +-------+--------+--------+----------------+-------------------+
+ * | Flags | Name | Value | Name String \0 | Data . . . . |
+ * | | Length | Length | | |
+ * +-------+--------+--------+----------------+-------------------+
+ *
+ * A jfs_ea_list then is structured as
+ *
+ * 0 4 4 + EA_SIZE(ea1)
+ * +------------+-------------------+--------------------+-----
+ * | Overall EA | First FEA Element | Second FEA Element | .....
+ * | List Size | | |
+ * +------------+-------------------+--------------------+-----
+ *
+ * On-disk:
+ *
+ * FEALISTs are stored on disk using blocks allocated by dbAlloc() and
+ * written directly. An EA list may be in-lined in the inode if there is
+ * sufficient room available.
+ */
+
+struct ea_buffer {
+ int flag; /* Indicates what storage xattr points to */
+ int max_size; /* largest xattr that fits in current buffer */
+ dxd_t new_ea; /* dxd to replace ea when modifying xattr */
+ struct metapage *mp; /* metapage containing ea list */
+ struct jfs_ea_list *xattr; /* buffer containing ea list */
+};
+
+/*
+ * ea_buffer.flag values
+ */
+#define EA_INLINE 0x0001
+#define EA_EXTENT 0x0002
+#define EA_NEW 0x0004
+#define EA_MALLOC 0x0008
+
+
+static int is_known_namespace(const char *name)
+{
+ if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
+ strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
+ strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
+ strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
+ return false;
+
+ return true;
+}
+
+/*
+ * These three routines are used to recognize on-disk extended attributes
+ * that are in a recognized namespace. If the attribute is not recognized,
+ * "os2." is prepended to the name
+ */
+static int is_os2_xattr(struct jfs_ea *ea)
+{
+ return !is_known_namespace(ea->name);
+}
+
+static inline int name_size(struct jfs_ea *ea)
+{
+ if (is_os2_xattr(ea))
+ return ea->namelen + XATTR_OS2_PREFIX_LEN;
+ else
+ return ea->namelen;
+}
+
+static inline int copy_name(char *buffer, struct jfs_ea *ea)
+{
+ int len = ea->namelen;
+
+ if (is_os2_xattr(ea)) {
+ memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN);
+ buffer += XATTR_OS2_PREFIX_LEN;
+ len += XATTR_OS2_PREFIX_LEN;
+ }
+ memcpy(buffer, ea->name, ea->namelen);
+ buffer[ea->namelen] = 0;
+
+ return len;
+}
+
+/* Forward references */
+static void ea_release(struct inode *inode, struct ea_buffer *ea_buf);
+
+/*
+ * NAME: ea_write_inline
+ *
+ * FUNCTION: Attempt to write an EA inline if area is available
+ *
+ * PRE CONDITIONS:
+ * Already verified that the specified EA is small enough to fit inline
+ *
+ * PARAMETERS:
+ * ip - Inode pointer
+ * ealist - EA list pointer
+ * size - size of ealist in bytes
+ * ea - dxd_t structure to be filled in with necessary EA information
+ * if we successfully copy the EA inline
+ *
+ * NOTES:
+ * Checks if the inode's inline area is available. If so, copies EA inline
+ * and sets <ea> fields appropriately. Otherwise, returns failure, EA will
+ * have to be put into an extent.
+ *
+ * RETURNS: 0 for successful copy to inline area; -1 if area not available
+ */
+static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist,
+ int size, dxd_t * ea)
+{
+ struct jfs_inode_info *ji = JFS_IP(ip);
+
+ /*
+ * Make sure we have an EA -- the NULL EA list is valid, but you
+ * can't copy it!
+ */
+ if (ealist && size > sizeof (struct jfs_ea_list)) {
+ assert(size <= sizeof (ji->i_inline_ea));
+
+ /*
+ * See if the space is available or if it is already being
+ * used for an inline EA.
+ */
+ if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE))
+ return -EPERM;
+
+ DXDsize(ea, size);
+ DXDlength(ea, 0);
+ DXDaddress(ea, 0);
+ memcpy(ji->i_inline_ea, ealist, size);
+ ea->flag = DXD_INLINE;
+ ji->mode2 &= ~INLINEEA;
+ } else {
+ ea->flag = 0;
+ DXDsize(ea, 0);
+ DXDlength(ea, 0);
+ DXDaddress(ea, 0);
+
+ /* Free up INLINE area */
+ if (ji->ea.flag & DXD_INLINE)
+ ji->mode2 |= INLINEEA;
+ }
+
+ return 0;
+}
+
+/*
+ * NAME: ea_write
+ *
+ * FUNCTION: Write an EA for an inode
+ *
+ * PRE CONDITIONS: EA has been verified
+ *
+ * PARAMETERS:
+ * ip - Inode pointer
+ * ealist - EA list pointer
+ * size - size of ealist in bytes
+ * ea - dxd_t structure to be filled in appropriately with where the
+ * EA was copied
+ *
+ * NOTES: Will write EA inline if able to, otherwise allocates blocks for an
+ * extent and synchronously writes it to those blocks.
+ *
+ * RETURNS: 0 for success; Anything else indicates failure
+ */
+static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size,
+ dxd_t * ea)
+{
+ struct super_block *sb = ip->i_sb;
+ struct jfs_inode_info *ji = JFS_IP(ip);
+ struct jfs_sb_info *sbi = JFS_SBI(sb);
+ int nblocks;
+ s64 blkno;
+ int rc = 0, i;
+ char *cp;
+ s32 nbytes, nb;
+ s32 bytes_to_write;
+ struct metapage *mp;
+
+ /*
+ * Quick check to see if this is an in-linable EA. Short EAs
+ * and empty EAs are all in-linable, provided the space exists.
+ */
+ if (!ealist || size <= sizeof (ji->i_inline_ea)) {
+ if (!ea_write_inline(ip, ealist, size, ea))
+ return 0;
+ }
+
+ /* figure out how many blocks we need */
+ nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits;
+
+ /* Allocate new blocks to quota. */
+ rc = dquot_alloc_block(ip, nblocks);
+ if (rc)
+ return rc;
+
+ rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno);
+ if (rc) {
+ /*Rollback quota allocation. */
+ dquot_free_block(ip, nblocks);
+ return rc;
+ }
+
+ /*
+ * Now have nblocks worth of storage to stuff into the FEALIST.
+ * loop over the FEALIST copying data into the buffer one page at
+ * a time.
+ */
+ cp = (char *) ealist;
+ nbytes = size;
+ for (i = 0; i < nblocks; i += sbi->nbperpage) {
+ /*
+ * Determine how many bytes for this request, and round up to
+ * the nearest aggregate block size
+ */
+ nb = min(PSIZE, nbytes);
+ bytes_to_write =
+ ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
+ << sb->s_blocksize_bits;
+
+ if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) {
+ rc = -EIO;
+ goto failed;
+ }
+
+ memcpy(mp->data, cp, nb);
+
+ /*
+ * We really need a way to propagate errors for
+ * forced writes like this one. --hch
+ *
+ * (__write_metapage => release_metapage => flush_metapage)
+ */
+#ifdef _JFS_FIXME
+ if ((rc = flush_metapage(mp))) {
+ /*
+ * the write failed -- this means that the buffer
+ * is still assigned and the blocks are not being
+ * used. this seems like the best error recovery
+ * we can get ...
+ */
+ goto failed;
+ }
+#else
+ flush_metapage(mp);
+#endif
+
+ cp += PSIZE;
+ nbytes -= nb;
+ }
+
+ ea->flag = DXD_EXTENT;
+ DXDsize(ea, le32_to_cpu(ealist->size));
+ DXDlength(ea, nblocks);
+ DXDaddress(ea, blkno);
+
+ /* Free up INLINE area */
+ if (ji->ea.flag & DXD_INLINE)
+ ji->mode2 |= INLINEEA;
+
+ return 0;
+
+ failed:
+ /* Rollback quota allocation. */
+ dquot_free_block(ip, nblocks);
+
+ dbFree(ip, blkno, nblocks);
+ return rc;
+}
+
+/*
+ * NAME: ea_read_inline
+ *
+ * FUNCTION: Read an inlined EA into user's buffer
+ *
+ * PARAMETERS:
+ * ip - Inode pointer
+ * ealist - Pointer to buffer to fill in with EA
+ *
+ * RETURNS: 0
+ */
+static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist)
+{
+ struct jfs_inode_info *ji = JFS_IP(ip);
+ int ea_size = sizeDXD(&ji->ea);
+
+ if (ea_size == 0) {
+ ealist->size = 0;
+ return 0;
+ }
+
+ /* Sanity Check */
+ if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea)))
+ return -EIO;
+ if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size)
+ != ea_size)
+ return -EIO;
+
+ memcpy(ealist, ji->i_inline_ea, ea_size);
+ return 0;
+}
+
+/*
+ * NAME: ea_read
+ *
+ * FUNCTION: copy EA data into user's buffer
+ *
+ * PARAMETERS:
+ * ip - Inode pointer
+ * ealist - Pointer to buffer to fill in with EA
+ *
+ * NOTES: If EA is inline calls ea_read_inline() to copy EA.
+ *
+ * RETURNS: 0 for success; other indicates failure
+ */
+static int ea_read(struct inode *ip, struct jfs_ea_list *ealist)
+{
+ struct super_block *sb = ip->i_sb;
+ struct jfs_inode_info *ji = JFS_IP(ip);
+ struct jfs_sb_info *sbi = JFS_SBI(sb);
+ int nblocks;
+ s64 blkno;
+ char *cp = (char *) ealist;
+ int i;
+ int nbytes, nb;
+ s32 bytes_to_read;
+ struct metapage *mp;
+
+ /* quick check for in-line EA */
+ if (ji->ea.flag & DXD_INLINE)
+ return ea_read_inline(ip, ealist);
+
+ nbytes = sizeDXD(&ji->ea);
+ if (!nbytes) {
+ jfs_error(sb, "nbytes is 0\n");
+ return -EIO;
+ }
+
+ /*
+ * Figure out how many blocks were allocated when this EA list was
+ * originally written to disk.
+ */
+ nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage;
+ blkno = addressDXD(&ji->ea) << sbi->l2nbperpage;
+
+ /*
+ * I have found the disk blocks which were originally used to store
+ * the FEALIST. now i loop over each contiguous block copying the
+ * data into the buffer.
+ */
+ for (i = 0; i < nblocks; i += sbi->nbperpage) {
+ /*
+ * Determine how many bytes for this request, and round up to
+ * the nearest aggregate block size
+ */
+ nb = min(PSIZE, nbytes);
+ bytes_to_read =
+ ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits))
+ << sb->s_blocksize_bits;
+
+ if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1)))
+ return -EIO;
+
+ memcpy(cp, mp->data, nb);
+ release_metapage(mp);
+
+ cp += PSIZE;
+ nbytes -= nb;
+ }
+
+ return 0;
+}
+
+/*
+ * NAME: ea_get
+ *
+ * FUNCTION: Returns buffer containing existing extended attributes.
+ * The size of the buffer will be the larger of the existing
+ * attributes size, or min_size.
+ *
+ * The buffer, which may be inlined in the inode or in the
+ * page cache must be release by calling ea_release or ea_put
+ *
+ * PARAMETERS:
+ * inode - Inode pointer
+ * ea_buf - Structure to be populated with ealist and its metadata
+ * min_size- minimum size of buffer to be returned
+ *
+ * RETURNS: 0 for success; Other indicates failure
+ */
+static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
+{
+ struct jfs_inode_info *ji = JFS_IP(inode);
+ struct super_block *sb = inode->i_sb;
+ int size;
+ int ea_size = sizeDXD(&ji->ea);
+ int blocks_needed, current_blocks;
+ s64 blkno;
+ int rc;
+ int quota_allocation = 0;
+
+ /* When fsck.jfs clears a bad ea, it doesn't clear the size */
+ if (ji->ea.flag == 0)
+ ea_size = 0;
+
+ if (ea_size == 0) {
+ if (min_size == 0) {
+ ea_buf->flag = 0;
+ ea_buf->max_size = 0;
+ ea_buf->xattr = NULL;
+ return 0;
+ }
+ if ((min_size <= sizeof (ji->i_inline_ea)) &&
+ (ji->mode2 & INLINEEA)) {
+ ea_buf->flag = EA_INLINE | EA_NEW;
+ ea_buf->max_size = sizeof (ji->i_inline_ea);
+ ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
+ DXDlength(&ea_buf->new_ea, 0);
+ DXDaddress(&ea_buf->new_ea, 0);
+ ea_buf->new_ea.flag = DXD_INLINE;
+ DXDsize(&ea_buf->new_ea, min_size);
+ return 0;
+ }
+ current_blocks = 0;
+ } else if (ji->ea.flag & DXD_INLINE) {
+ if (min_size <= sizeof (ji->i_inline_ea)) {
+ ea_buf->flag = EA_INLINE;
+ ea_buf->max_size = sizeof (ji->i_inline_ea);
+ ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea;
+ goto size_check;
+ }
+ current_blocks = 0;
+ } else {
+ if (!(ji->ea.flag & DXD_EXTENT)) {
+ jfs_error(sb, "invalid ea.flag\n");
+ return -EIO;
+ }
+ current_blocks = (ea_size + sb->s_blocksize - 1) >>
+ sb->s_blocksize_bits;
+ }
+ size = max(min_size, ea_size);
+
+ if (size > PSIZE) {
+ /*
+ * To keep the rest of the code simple. Allocate a
+ * contiguous buffer to work with
+ */
+ ea_buf->xattr = kmalloc(size, GFP_KERNEL);
+ if (ea_buf->xattr == NULL)
+ return -ENOMEM;
+
+ ea_buf->flag = EA_MALLOC;
+ ea_buf->max_size = (size + sb->s_blocksize - 1) &
+ ~(sb->s_blocksize - 1);
+
+ if (ea_size == 0)
+ return 0;
+
+ if ((rc = ea_read(inode, ea_buf->xattr))) {
+ kfree(ea_buf->xattr);
+ ea_buf->xattr = NULL;
+ return rc;
+ }
+ goto size_check;
+ }
+ blocks_needed = (min_size + sb->s_blocksize - 1) >>
+ sb->s_blocksize_bits;
+
+ if (blocks_needed > current_blocks) {
+ /* Allocate new blocks to quota. */
+ rc = dquot_alloc_block(inode, blocks_needed);
+ if (rc)
+ return -EDQUOT;
+
+ quota_allocation = blocks_needed;
+
+ rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed,
+ &blkno);
+ if (rc)
+ goto clean_up;
+
+ DXDlength(&ea_buf->new_ea, blocks_needed);
+ DXDaddress(&ea_buf->new_ea, blkno);
+ ea_buf->new_ea.flag = DXD_EXTENT;
+ DXDsize(&ea_buf->new_ea, min_size);
+
+ ea_buf->flag = EA_EXTENT | EA_NEW;
+
+ ea_buf->mp = get_metapage(inode, blkno,
+ blocks_needed << sb->s_blocksize_bits,
+ 1);
+ if (ea_buf->mp == NULL) {
+ dbFree(inode, blkno, (s64) blocks_needed);
+ rc = -EIO;
+ goto clean_up;
+ }
+ ea_buf->xattr = ea_buf->mp->data;
+ ea_buf->max_size = (min_size + sb->s_blocksize - 1) &
+ ~(sb->s_blocksize - 1);
+ if (ea_size == 0)
+ return 0;
+ if ((rc = ea_read(inode, ea_buf->xattr))) {
+ discard_metapage(ea_buf->mp);
+ dbFree(inode, blkno, (s64) blocks_needed);
+ goto clean_up;
+ }
+ goto size_check;
+ }
+ ea_buf->flag = EA_EXTENT;
+ ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea),
+ lengthDXD(&ji->ea) << sb->s_blocksize_bits,
+ 1);
+ if (ea_buf->mp == NULL) {
+ rc = -EIO;
+ goto clean_up;
+ }
+ ea_buf->xattr = ea_buf->mp->data;
+ ea_buf->max_size = (ea_size + sb->s_blocksize - 1) &
+ ~(sb->s_blocksize - 1);
+
+ size_check:
+ if (EALIST_SIZE(ea_buf->xattr) != ea_size) {
+ printk(KERN_ERR "ea_get: invalid extended attribute\n");
+ print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
+ ea_buf->xattr, ea_size, 1);
+ ea_release(inode, ea_buf);
+ rc = -EIO;
+ goto clean_up;
+ }
+
+ return ea_size;
+
+ clean_up:
+ /* Rollback quota allocation */
+ if (quota_allocation)
+ dquot_free_block(inode, quota_allocation);
+
+ return (rc);
+}
+
+static void ea_release(struct inode *inode, struct ea_buffer *ea_buf)
+{
+ if (ea_buf->flag & EA_MALLOC)
+ kfree(ea_buf->xattr);
+ else if (ea_buf->flag & EA_EXTENT) {
+ assert(ea_buf->mp);
+ release_metapage(ea_buf->mp);
+
+ if (ea_buf->flag & EA_NEW)
+ dbFree(inode, addressDXD(&ea_buf->new_ea),
+ lengthDXD(&ea_buf->new_ea));
+ }
+}
+
+static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf,
+ int new_size)
+{
+ struct jfs_inode_info *ji = JFS_IP(inode);
+ unsigned long old_blocks, new_blocks;
+ int rc = 0;
+
+ if (new_size == 0) {
+ ea_release(inode, ea_buf);
+ ea_buf = NULL;
+ } else if (ea_buf->flag & EA_INLINE) {
+ assert(new_size <= sizeof (ji->i_inline_ea));
+ ji->mode2 &= ~INLINEEA;
+ ea_buf->new_ea.flag = DXD_INLINE;
+ DXDsize(&ea_buf->new_ea, new_size);
+ DXDaddress(&ea_buf->new_ea, 0);
+ DXDlength(&ea_buf->new_ea, 0);
+ } else if (ea_buf->flag & EA_MALLOC) {
+ rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
+ kfree(ea_buf->xattr);
+ } else if (ea_buf->flag & EA_NEW) {
+ /* We have already allocated a new dxd */
+ flush_metapage(ea_buf->mp);
+ } else {
+ /* ->xattr must point to original ea's metapage */
+ rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea);
+ discard_metapage(ea_buf->mp);
+ }
+ if (rc)
+ return rc;
+
+ old_blocks = new_blocks = 0;
+
+ if (ji->ea.flag & DXD_EXTENT) {
+ invalidate_dxd_metapages(inode, ji->ea);
+ old_blocks = lengthDXD(&ji->ea);
+ }
+
+ if (ea_buf) {
+ txEA(tid, inode, &ji->ea, &ea_buf->new_ea);
+ if (ea_buf->new_ea.flag & DXD_EXTENT) {
+ new_blocks = lengthDXD(&ea_buf->new_ea);
+ if (ji->ea.flag & DXD_INLINE)
+ ji->mode2 |= INLINEEA;
+ }
+ ji->ea = ea_buf->new_ea;
+ } else {
+ txEA(tid, inode, &ji->ea, NULL);
+ if (ji->ea.flag & DXD_INLINE)
+ ji->mode2 |= INLINEEA;
+ ji->ea.flag = 0;
+ ji->ea.size = 0;
+ }
+
+ /* If old blocks exist, they must be removed from quota allocation. */
+ if (old_blocks)
+ dquot_free_block(inode, old_blocks);
+
+ inode->i_ctime = CURRENT_TIME;
+
+ return 0;
+}
+
+/*
+ * Most of the permission checking is done by xattr_permission in the vfs.
+ * We also need to verify that this is a namespace that we recognize.
+ */
+static int can_set_xattr(struct inode *inode, const char *name,
+ const void *value, size_t value_len)
+{
+ if (!strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)) {
+ /*
+ * This makes sure that we aren't trying to set an
+ * attribute in a different namespace by prefixing it
+ * with "os2."
+ */
+ if (is_known_namespace(name + XATTR_OS2_PREFIX_LEN))
+ return -EOPNOTSUPP;
+ return 0;
+ }
+
+ /*
+ * Don't allow setting an attribute in an unknown namespace.
+ */
+ if (strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) &&
+ strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
+ strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
+ return -EOPNOTSUPP;
+
+ return 0;
+}
+
+int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name,
+ const void *value, size_t value_len, int flags)
+{
+ struct jfs_ea_list *ealist;
+ struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL;
+ struct ea_buffer ea_buf;
+ int old_ea_size = 0;
+ int xattr_size;
+ int new_size;
+ int namelen = strlen(name);
+ char *os2name = NULL;
+ int found = 0;
+ int rc;
+ int length;
+
+ if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
+ os2name = kmalloc(namelen - XATTR_OS2_PREFIX_LEN + 1,
+ GFP_KERNEL);
+ if (!os2name)
+ return -ENOMEM;
+ strcpy(os2name, name + XATTR_OS2_PREFIX_LEN);
+ name = os2name;
+ namelen -= XATTR_OS2_PREFIX_LEN;
+ }
+
+ down_write(&JFS_IP(inode)->xattr_sem);
+
+ xattr_size = ea_get(inode, &ea_buf, 0);
+ if (xattr_size < 0) {
+ rc = xattr_size;
+ goto out;
+ }
+
+ again:
+ ealist = (struct jfs_ea_list *) ea_buf.xattr;
+ new_size = sizeof (struct jfs_ea_list);
+
+ if (xattr_size) {
+ for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist);
+ ea = NEXT_EA(ea)) {
+ if ((namelen == ea->namelen) &&
+ (memcmp(name, ea->name, namelen) == 0)) {
+ found = 1;
+ if (flags & XATTR_CREATE) {
+ rc = -EEXIST;
+ goto release;
+ }
+ old_ea = ea;
+ old_ea_size = EA_SIZE(ea);
+ next_ea = NEXT_EA(ea);
+ } else
+ new_size += EA_SIZE(ea);
+ }
+ }
+
+ if (!found) {
+ if (flags & XATTR_REPLACE) {
+ rc = -ENODATA;
+ goto release;
+ }
+ if (value == NULL) {
+ rc = 0;
+ goto release;
+ }
+ }
+ if (value)
+ new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len;
+
+ if (new_size > ea_buf.max_size) {
+ /*
+ * We need to allocate more space for merged ea list.
+ * We should only have loop to again: once.
+ */
+ ea_release(inode, &ea_buf);
+ xattr_size = ea_get(inode, &ea_buf, new_size);
+ if (xattr_size < 0) {
+ rc = xattr_size;
+ goto out;
+ }
+ goto again;
+ }
+
+ /* Remove old ea of the same name */
+ if (found) {
+ /* number of bytes following target EA */
+ length = (char *) END_EALIST(ealist) - (char *) next_ea;
+ if (length > 0)
+ memmove(old_ea, next_ea, length);
+ xattr_size -= old_ea_size;
+ }
+
+ /* Add new entry to the end */
+ if (value) {
+ if (xattr_size == 0)
+ /* Completely new ea list */
+ xattr_size = sizeof (struct jfs_ea_list);
+
+ /*
+ * The size of EA value is limitted by on-disk format up to
+ * __le16, there would be an overflow if the size is equal
+ * to XATTR_SIZE_MAX (65536). In order to avoid this issue,
+ * we can pre-checkup the value size against USHRT_MAX, and
+ * return -E2BIG in this case, which is consistent with the
+ * VFS setxattr interface.
+ */
+ if (value_len >= USHRT_MAX) {
+ rc = -E2BIG;
+ goto release;
+ }
+
+ ea = (struct jfs_ea *) ((char *) ealist + xattr_size);
+ ea->flag = 0;
+ ea->namelen = namelen;
+ ea->valuelen = (cpu_to_le16(value_len));
+ memcpy(ea->name, name, namelen);
+ ea->name[namelen] = 0;
+ if (value_len)
+ memcpy(&ea->name[namelen + 1], value, value_len);
+ xattr_size += EA_SIZE(ea);
+ }
+
+ /* DEBUG - If we did this right, these number match */
+ if (xattr_size != new_size) {
+ printk(KERN_ERR
+ "__jfs_setxattr: xattr_size = %d, new_size = %d\n",
+ xattr_size, new_size);
+
+ rc = -EINVAL;
+ goto release;
+ }
+
+ /*
+ * If we're left with an empty list, there's no ea
+ */
+ if (new_size == sizeof (struct jfs_ea_list))
+ new_size = 0;
+
+ ealist->size = cpu_to_le32(new_size);
+
+ rc = ea_put(tid, inode, &ea_buf, new_size);
+
+ goto out;
+ release:
+ ea_release(inode, &ea_buf);
+ out:
+ up_write(&JFS_IP(inode)->xattr_sem);
+
+ kfree(os2name);
+
+ return rc;
+}
+
+int jfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+ size_t value_len, int flags)
+{
+ struct inode *inode = d_inode(dentry);
+ struct jfs_inode_info *ji = JFS_IP(inode);
+ int rc;
+ tid_t tid;
+
+ /*
+ * If this is a request for a synthetic attribute in the system.*
+ * namespace use the generic infrastructure to resolve a handler
+ * for it via sb->s_xattr.
+ */
+ if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+ return generic_setxattr(dentry, name, value, value_len, flags);
+
+ if ((rc = can_set_xattr(inode, name, value, value_len)))
+ return rc;
+
+ if (value == NULL) { /* empty EA, do not remove */
+ value = "";
+ value_len = 0;
+ }
+
+ tid = txBegin(inode->i_sb, 0);
+ mutex_lock(&ji->commit_mutex);
+ rc = __jfs_setxattr(tid, d_inode(dentry), name, value, value_len,
+ flags);
+ if (!rc)
+ rc = txCommit(tid, 1, &inode, 0);
+ txEnd(tid);
+ mutex_unlock(&ji->commit_mutex);
+
+ return rc;
+}
+
+ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data,
+ size_t buf_size)
+{
+ struct jfs_ea_list *ealist;
+ struct jfs_ea *ea;
+ struct ea_buffer ea_buf;
+ int xattr_size;
+ ssize_t size;
+ int namelen = strlen(name);
+ char *value;
+
+ down_read(&JFS_IP(inode)->xattr_sem);
+
+ xattr_size = ea_get(inode, &ea_buf, 0);
+
+ if (xattr_size < 0) {
+ size = xattr_size;
+ goto out;
+ }
+
+ if (xattr_size == 0)
+ goto not_found;
+
+ ealist = (struct jfs_ea_list *) ea_buf.xattr;
+
+ /* Find the named attribute */
+ for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea))
+ if ((namelen == ea->namelen) &&
+ memcmp(name, ea->name, namelen) == 0) {
+ /* Found it */
+ size = le16_to_cpu(ea->valuelen);
+ if (!data)
+ goto release;
+ else if (size > buf_size) {
+ size = -ERANGE;
+ goto release;
+ }
+ value = ((char *) &ea->name) + ea->namelen + 1;
+ memcpy(data, value, size);
+ goto release;
+ }
+ not_found:
+ size = -ENODATA;
+ release:
+ ea_release(inode, &ea_buf);
+ out:
+ up_read(&JFS_IP(inode)->xattr_sem);
+
+ return size;
+}
+
+ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data,
+ size_t buf_size)
+{
+ int err;
+
+ /*
+ * If this is a request for a synthetic attribute in the system.*
+ * namespace use the generic infrastructure to resolve a handler
+ * for it via sb->s_xattr.
+ */
+ if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+ return generic_getxattr(dentry, name, data, buf_size);
+
+ if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
+ /*
+ * skip past "os2." prefix
+ */
+ name += XATTR_OS2_PREFIX_LEN;
+ /*
+ * Don't allow retrieving properly prefixed attributes
+ * by prepending them with "os2."
+ */
+ if (is_known_namespace(name))
+ return -EOPNOTSUPP;
+ }
+
+ err = __jfs_getxattr(d_inode(dentry), name, data, buf_size);
+
+ return err;
+}
+
+/*
+ * No special permissions are needed to list attributes except for trusted.*
+ */
+static inline int can_list(struct jfs_ea *ea)
+{
+ return (strncmp(ea->name, XATTR_TRUSTED_PREFIX,
+ XATTR_TRUSTED_PREFIX_LEN) ||
+ capable(CAP_SYS_ADMIN));
+}
+
+ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size)
+{
+ struct inode *inode = d_inode(dentry);
+ char *buffer;
+ ssize_t size = 0;
+ int xattr_size;
+ struct jfs_ea_list *ealist;
+ struct jfs_ea *ea;
+ struct ea_buffer ea_buf;
+
+ down_read(&JFS_IP(inode)->xattr_sem);
+
+ xattr_size = ea_get(inode, &ea_buf, 0);
+ if (xattr_size < 0) {
+ size = xattr_size;
+ goto out;
+ }
+
+ if (xattr_size == 0)
+ goto release;
+
+ ealist = (struct jfs_ea_list *) ea_buf.xattr;
+
+ /* compute required size of list */
+ for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
+ if (can_list(ea))
+ size += name_size(ea) + 1;
+ }
+
+ if (!data)
+ goto release;
+
+ if (size > buf_size) {
+ size = -ERANGE;
+ goto release;
+ }
+
+ /* Copy attribute names to buffer */
+ buffer = data;
+ for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) {
+ if (can_list(ea)) {
+ int namelen = copy_name(buffer, ea);
+ buffer += namelen + 1;
+ }
+ }
+
+ release:
+ ea_release(inode, &ea_buf);
+ out:
+ up_read(&JFS_IP(inode)->xattr_sem);
+ return size;
+}
+
+int jfs_removexattr(struct dentry *dentry, const char *name)
+{
+ struct inode *inode = d_inode(dentry);
+ struct jfs_inode_info *ji = JFS_IP(inode);
+ int rc;
+ tid_t tid;
+
+ /*
+ * If this is a request for a synthetic attribute in the system.*
+ * namespace use the generic infrastructure to resolve a handler
+ * for it via sb->s_xattr.
+ */
+ if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+ return generic_removexattr(dentry, name);
+
+ if ((rc = can_set_xattr(inode, name, NULL, 0)))
+ return rc;
+
+ tid = txBegin(inode->i_sb, 0);
+ mutex_lock(&ji->commit_mutex);
+ rc = __jfs_setxattr(tid, d_inode(dentry), name, NULL, 0, XATTR_REPLACE);
+ if (!rc)
+ rc = txCommit(tid, 1, &inode, 0);
+ txEnd(tid);
+ mutex_unlock(&ji->commit_mutex);
+
+ return rc;
+}
+
+/*
+ * List of handlers for synthetic system.* attributes. All real ondisk
+ * attributes are handled directly.
+ */
+const struct xattr_handler *jfs_xattr_handlers[] = {
+#ifdef CONFIG_JFS_POSIX_ACL
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+#endif
+ NULL,
+};
+
+
+#ifdef CONFIG_JFS_SECURITY
+static int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
+ void *fs_info)
+{
+ const struct xattr *xattr;
+ tid_t *tid = fs_info;
+ char *name;
+ int err = 0;
+
+ for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+ name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
+ strlen(xattr->name) + 1, GFP_NOFS);
+ if (!name) {
+ err = -ENOMEM;
+ break;
+ }
+ strcpy(name, XATTR_SECURITY_PREFIX);
+ strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
+
+ err = __jfs_setxattr(*tid, inode, name,
+ xattr->value, xattr->value_len, 0);
+ kfree(name);
+ if (err < 0)
+ break;
+ }
+ return err;
+}
+
+int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir,
+ const struct qstr *qstr)
+{
+ return security_inode_init_security(inode, dir, qstr,
+ &jfs_initxattrs, &tid);
+}
+#endif
Code Review / kvmfornfv.git / blobdiff