| /* |
| * linux/fs/ufs/truncate.c |
| * |
| * Copyright (C) 1998 |
| * Daniel Pirkl <daniel.pirkl@email.cz> |
| * Charles University, Faculty of Mathematics and Physics |
| * |
| * from |
| * |
| * linux/fs/ext2/truncate.c |
| * |
| * Copyright (C) 1992, 1993, 1994, 1995 |
| * Remy Card (card@masi.ibp.fr) |
| * Laboratoire MASI - Institut Blaise Pascal |
| * Universite Pierre et Marie Curie (Paris VI) |
| * |
| * from |
| * |
| * linux/fs/minix/truncate.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * |
| * Big-endian to little-endian byte-swapping/bitmaps by |
| * David S. Miller (davem@caip.rutgers.edu), 1995 |
| */ |
| |
| /* |
| * Real random numbers for secure rm added 94/02/18 |
| * Idea from Pierre del Perugia <delperug@gla.ecoledoc.ibp.fr> |
| */ |
| |
| /* |
| * Modified to avoid infinite loop on 2006 by |
| * Evgeniy Dushistov <dushistov@mail.ru> |
| */ |
| |
| #include <linux/errno.h> |
| #include <linux/fs.h> |
| #include <linux/ufs_fs.h> |
| #include <linux/fcntl.h> |
| #include <linux/time.h> |
| #include <linux/stat.h> |
| #include <linux/string.h> |
| #include <linux/smp_lock.h> |
| #include <linux/buffer_head.h> |
| #include <linux/blkdev.h> |
| #include <linux/sched.h> |
| |
| #include "swab.h" |
| #include "util.h" |
| |
| /* |
| * Secure deletion currently doesn't work. It interacts very badly |
| * with buffers shared with memory mappings, and for that reason |
| * can't be done in the truncate() routines. It should instead be |
| * done separately in "release()" before calling the truncate routines |
| * that will release the actual file blocks. |
| * |
| * Linus |
| */ |
| |
| #define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift) |
| #define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift) |
| |
| |
| static int ufs_trunc_direct (struct inode * inode) |
| { |
| struct ufs_inode_info *ufsi = UFS_I(inode); |
| struct super_block * sb; |
| struct ufs_sb_private_info * uspi; |
| __fs32 * p; |
| unsigned frag1, frag2, frag3, frag4, block1, block2; |
| unsigned frag_to_free, free_count; |
| unsigned i, tmp; |
| int retry; |
| |
| UFSD("ENTER\n"); |
| |
| sb = inode->i_sb; |
| uspi = UFS_SB(sb)->s_uspi; |
| |
| frag_to_free = 0; |
| free_count = 0; |
| retry = 0; |
| |
| frag1 = DIRECT_FRAGMENT; |
| frag4 = min_t(u32, UFS_NDIR_FRAGMENT, ufsi->i_lastfrag); |
| frag2 = ((frag1 & uspi->s_fpbmask) ? ((frag1 | uspi->s_fpbmask) + 1) : frag1); |
| frag3 = frag4 & ~uspi->s_fpbmask; |
| block1 = block2 = 0; |
| if (frag2 > frag3) { |
| frag2 = frag4; |
| frag3 = frag4 = 0; |
| } |
| else if (frag2 < frag3) { |
| block1 = ufs_fragstoblks (frag2); |
| block2 = ufs_fragstoblks (frag3); |
| } |
| |
| UFSD("frag1 %u, frag2 %u, block1 %u, block2 %u, frag3 %u, frag4 %u\n", frag1, frag2, block1, block2, frag3, frag4); |
| |
| if (frag1 >= frag2) |
| goto next1; |
| |
| /* |
| * Free first free fragments |
| */ |
| p = ufsi->i_u1.i_data + ufs_fragstoblks (frag1); |
| tmp = fs32_to_cpu(sb, *p); |
| if (!tmp ) |
| ufs_panic (sb, "ufs_trunc_direct", "internal error"); |
| frag2 -= frag1; |
| frag1 = ufs_fragnum (frag1); |
| |
| ufs_free_fragments(inode, tmp + frag1, frag2); |
| mark_inode_dirty(inode); |
| frag_to_free = tmp + frag1; |
| |
| next1: |
| /* |
| * Free whole blocks |
| */ |
| for (i = block1 ; i < block2; i++) { |
| p = ufsi->i_u1.i_data + i; |
| tmp = fs32_to_cpu(sb, *p); |
| if (!tmp) |
| continue; |
| |
| *p = 0; |
| |
| if (free_count == 0) { |
| frag_to_free = tmp; |
| free_count = uspi->s_fpb; |
| } else if (free_count > 0 && frag_to_free == tmp - free_count) |
| free_count += uspi->s_fpb; |
| else { |
| ufs_free_blocks (inode, frag_to_free, free_count); |
| frag_to_free = tmp; |
| free_count = uspi->s_fpb; |
| } |
| mark_inode_dirty(inode); |
| } |
| |
| if (free_count > 0) |
| ufs_free_blocks (inode, frag_to_free, free_count); |
| |
| if (frag3 >= frag4) |
| goto next3; |
| |
| /* |
| * Free last free fragments |
| */ |
| p = ufsi->i_u1.i_data + ufs_fragstoblks (frag3); |
| tmp = fs32_to_cpu(sb, *p); |
| if (!tmp ) |
| ufs_panic(sb, "ufs_truncate_direct", "internal error"); |
| frag4 = ufs_fragnum (frag4); |
| |
| *p = 0; |
| |
| ufs_free_fragments (inode, tmp, frag4); |
| mark_inode_dirty(inode); |
| next3: |
| |
| UFSD("EXIT\n"); |
| return retry; |
| } |
| |
| |
| static int ufs_trunc_indirect (struct inode * inode, unsigned offset, __fs32 *p) |
| { |
| struct super_block * sb; |
| struct ufs_sb_private_info * uspi; |
| struct ufs_buffer_head * ind_ubh; |
| __fs32 * ind; |
| unsigned indirect_block, i, tmp; |
| unsigned frag_to_free, free_count; |
| int retry; |
| |
| UFSD("ENTER\n"); |
| |
| sb = inode->i_sb; |
| uspi = UFS_SB(sb)->s_uspi; |
| |
| frag_to_free = 0; |
| free_count = 0; |
| retry = 0; |
| |
| tmp = fs32_to_cpu(sb, *p); |
| if (!tmp) |
| return 0; |
| ind_ubh = ubh_bread(sb, tmp, uspi->s_bsize); |
| if (tmp != fs32_to_cpu(sb, *p)) { |
| ubh_brelse (ind_ubh); |
| return 1; |
| } |
| if (!ind_ubh) { |
| *p = 0; |
| return 0; |
| } |
| |
| indirect_block = (DIRECT_BLOCK > offset) ? (DIRECT_BLOCK - offset) : 0; |
| for (i = indirect_block; i < uspi->s_apb; i++) { |
| ind = ubh_get_addr32 (ind_ubh, i); |
| tmp = fs32_to_cpu(sb, *ind); |
| if (!tmp) |
| continue; |
| |
| *ind = 0; |
| ubh_mark_buffer_dirty(ind_ubh); |
| if (free_count == 0) { |
| frag_to_free = tmp; |
| free_count = uspi->s_fpb; |
| } else if (free_count > 0 && frag_to_free == tmp - free_count) |
| free_count += uspi->s_fpb; |
| else { |
| ufs_free_blocks (inode, frag_to_free, free_count); |
| frag_to_free = tmp; |
| free_count = uspi->s_fpb; |
| } |
| |
| mark_inode_dirty(inode); |
| } |
| |
| if (free_count > 0) { |
| ufs_free_blocks (inode, frag_to_free, free_count); |
| } |
| for (i = 0; i < uspi->s_apb; i++) |
| if (*ubh_get_addr32(ind_ubh,i)) |
| break; |
| if (i >= uspi->s_apb) { |
| tmp = fs32_to_cpu(sb, *p); |
| *p = 0; |
| |
| ufs_free_blocks (inode, tmp, uspi->s_fpb); |
| mark_inode_dirty(inode); |
| ubh_bforget(ind_ubh); |
| ind_ubh = NULL; |
| } |
| if (IS_SYNC(inode) && ind_ubh && ubh_buffer_dirty(ind_ubh)) { |
| ubh_ll_rw_block(SWRITE, ind_ubh); |
| ubh_wait_on_buffer (ind_ubh); |
| } |
| ubh_brelse (ind_ubh); |
| |
| UFSD("EXIT\n"); |
| |
| return retry; |
| } |
| |
| static int ufs_trunc_dindirect (struct inode *inode, unsigned offset, __fs32 *p) |
| { |
| struct super_block * sb; |
| struct ufs_sb_private_info * uspi; |
| struct ufs_buffer_head * dind_bh; |
| unsigned i, tmp, dindirect_block; |
| __fs32 * dind; |
| int retry = 0; |
| |
| UFSD("ENTER\n"); |
| |
| sb = inode->i_sb; |
| uspi = UFS_SB(sb)->s_uspi; |
| |
| dindirect_block = (DIRECT_BLOCK > offset) |
| ? ((DIRECT_BLOCK - offset) >> uspi->s_apbshift) : 0; |
| retry = 0; |
| |
| tmp = fs32_to_cpu(sb, *p); |
| if (!tmp) |
| return 0; |
| dind_bh = ubh_bread(sb, tmp, uspi->s_bsize); |
| if (tmp != fs32_to_cpu(sb, *p)) { |
| ubh_brelse (dind_bh); |
| return 1; |
| } |
| if (!dind_bh) { |
| *p = 0; |
| return 0; |
| } |
| |
| for (i = dindirect_block ; i < uspi->s_apb ; i++) { |
| dind = ubh_get_addr32 (dind_bh, i); |
| tmp = fs32_to_cpu(sb, *dind); |
| if (!tmp) |
| continue; |
| retry |= ufs_trunc_indirect (inode, offset + (i << uspi->s_apbshift), dind); |
| ubh_mark_buffer_dirty(dind_bh); |
| } |
| |
| for (i = 0; i < uspi->s_apb; i++) |
| if (*ubh_get_addr32 (dind_bh, i)) |
| break; |
| if (i >= uspi->s_apb) { |
| tmp = fs32_to_cpu(sb, *p); |
| *p = 0; |
| |
| ufs_free_blocks(inode, tmp, uspi->s_fpb); |
| mark_inode_dirty(inode); |
| ubh_bforget(dind_bh); |
| dind_bh = NULL; |
| } |
| if (IS_SYNC(inode) && dind_bh && ubh_buffer_dirty(dind_bh)) { |
| ubh_ll_rw_block(SWRITE, dind_bh); |
| ubh_wait_on_buffer (dind_bh); |
| } |
| ubh_brelse (dind_bh); |
| |
| UFSD("EXIT\n"); |
| |
| return retry; |
| } |
| |
| static int ufs_trunc_tindirect (struct inode * inode) |
| { |
| struct ufs_inode_info *ufsi = UFS_I(inode); |
| struct super_block * sb; |
| struct ufs_sb_private_info * uspi; |
| struct ufs_buffer_head * tind_bh; |
| unsigned tindirect_block, tmp, i; |
| __fs32 * tind, * p; |
| int retry; |
| |
| UFSD("ENTER\n"); |
| |
| sb = inode->i_sb; |
| uspi = UFS_SB(sb)->s_uspi; |
| retry = 0; |
| |
| tindirect_block = (DIRECT_BLOCK > (UFS_NDADDR + uspi->s_apb + uspi->s_2apb)) |
| ? ((DIRECT_BLOCK - UFS_NDADDR - uspi->s_apb - uspi->s_2apb) >> uspi->s_2apbshift) : 0; |
| p = ufsi->i_u1.i_data + UFS_TIND_BLOCK; |
| if (!(tmp = fs32_to_cpu(sb, *p))) |
| return 0; |
| tind_bh = ubh_bread (sb, tmp, uspi->s_bsize); |
| if (tmp != fs32_to_cpu(sb, *p)) { |
| ubh_brelse (tind_bh); |
| return 1; |
| } |
| if (!tind_bh) { |
| *p = 0; |
| return 0; |
| } |
| |
| for (i = tindirect_block ; i < uspi->s_apb ; i++) { |
| tind = ubh_get_addr32 (tind_bh, i); |
| retry |= ufs_trunc_dindirect(inode, UFS_NDADDR + |
| uspi->s_apb + ((i + 1) << uspi->s_2apbshift), tind); |
| ubh_mark_buffer_dirty(tind_bh); |
| } |
| for (i = 0; i < uspi->s_apb; i++) |
| if (*ubh_get_addr32 (tind_bh, i)) |
| break; |
| if (i >= uspi->s_apb) { |
| tmp = fs32_to_cpu(sb, *p); |
| *p = 0; |
| |
| ufs_free_blocks(inode, tmp, uspi->s_fpb); |
| mark_inode_dirty(inode); |
| ubh_bforget(tind_bh); |
| tind_bh = NULL; |
| } |
| if (IS_SYNC(inode) && tind_bh && ubh_buffer_dirty(tind_bh)) { |
| ubh_ll_rw_block(SWRITE, tind_bh); |
| ubh_wait_on_buffer (tind_bh); |
| } |
| ubh_brelse (tind_bh); |
| |
| UFSD("EXIT\n"); |
| return retry; |
| } |
| |
| static int ufs_alloc_lastblock(struct inode *inode) |
| { |
| int err = 0; |
| struct address_space *mapping = inode->i_mapping; |
| struct ufs_sb_private_info *uspi = UFS_SB(inode->i_sb)->s_uspi; |
| unsigned lastfrag, i, end; |
| struct page *lastpage; |
| struct buffer_head *bh; |
| |
| lastfrag = (i_size_read(inode) + uspi->s_fsize - 1) >> uspi->s_fshift; |
| |
| if (!lastfrag) |
| goto out; |
| |
| lastfrag--; |
| |
| lastpage = ufs_get_locked_page(mapping, lastfrag >> |
| (PAGE_CACHE_SHIFT - inode->i_blkbits)); |
| if (IS_ERR(lastpage)) { |
| err = -EIO; |
| goto out; |
| } |
| |
| end = lastfrag & ((1 << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - 1); |
| bh = page_buffers(lastpage); |
| for (i = 0; i < end; ++i) |
| bh = bh->b_this_page; |
| |
| |
| err = ufs_getfrag_block(inode, lastfrag, bh, 1); |
| |
| if (unlikely(err)) |
| goto out_unlock; |
| |
| if (buffer_new(bh)) { |
| clear_buffer_new(bh); |
| unmap_underlying_metadata(bh->b_bdev, |
| bh->b_blocknr); |
| /* |
| * we do not zeroize fragment, because of |
| * if it maped to hole, it already contains zeroes |
| */ |
| set_buffer_uptodate(bh); |
| mark_buffer_dirty(bh); |
| set_page_dirty(lastpage); |
| } |
| |
| out_unlock: |
| ufs_put_locked_page(lastpage); |
| out: |
| return err; |
| } |
| |
| int ufs_truncate(struct inode *inode, loff_t old_i_size) |
| { |
| struct ufs_inode_info *ufsi = UFS_I(inode); |
| struct super_block *sb = inode->i_sb; |
| struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi; |
| int retry, err = 0; |
| |
| UFSD("ENTER\n"); |
| |
| if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || |
| S_ISLNK(inode->i_mode))) |
| return -EINVAL; |
| if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) |
| return -EPERM; |
| |
| err = ufs_alloc_lastblock(inode); |
| |
| if (err) { |
| i_size_write(inode, old_i_size); |
| goto out; |
| } |
| |
| block_truncate_page(inode->i_mapping, inode->i_size, ufs_getfrag_block); |
| |
| lock_kernel(); |
| while (1) { |
| retry = ufs_trunc_direct(inode); |
| retry |= ufs_trunc_indirect (inode, UFS_IND_BLOCK, |
| (__fs32 *) &ufsi->i_u1.i_data[UFS_IND_BLOCK]); |
| retry |= ufs_trunc_dindirect (inode, UFS_IND_BLOCK + uspi->s_apb, |
| (__fs32 *) &ufsi->i_u1.i_data[UFS_DIND_BLOCK]); |
| retry |= ufs_trunc_tindirect (inode); |
| if (!retry) |
| break; |
| if (IS_SYNC(inode) && (inode->i_state & I_DIRTY)) |
| ufs_sync_inode (inode); |
| blk_run_address_space(inode->i_mapping); |
| yield(); |
| } |
| |
| inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; |
| ufsi->i_lastfrag = DIRECT_FRAGMENT; |
| unlock_kernel(); |
| mark_inode_dirty(inode); |
| out: |
| UFSD("EXIT: err %d\n", err); |
| return err; |
| } |
| |
| |
| /* |
| * We don't define our `inode->i_op->truncate', and call it here, |
| * because of: |
| * - there is no way to know old size |
| * - there is no way inform user about error, if it happens in `truncate' |
| */ |
| static int ufs_setattr(struct dentry *dentry, struct iattr *attr) |
| { |
| struct inode *inode = dentry->d_inode; |
| unsigned int ia_valid = attr->ia_valid; |
| int error; |
| |
| error = inode_change_ok(inode, attr); |
| if (error) |
| return error; |
| |
| if (ia_valid & ATTR_SIZE && |
| attr->ia_size != i_size_read(inode)) { |
| loff_t old_i_size = inode->i_size; |
| error = vmtruncate(inode, attr->ia_size); |
| if (error) |
| return error; |
| error = ufs_truncate(inode, old_i_size); |
| if (error) |
| return error; |
| } |
| return inode_setattr(inode, attr); |
| } |
| |
| struct inode_operations ufs_file_inode_operations = { |
| .setattr = ufs_setattr, |
| }; |