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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/ufs/truncate.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/ufs/truncate.c')
-rw-r--r-- | fs/ufs/truncate.c | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/fs/ufs/truncate.c b/fs/ufs/truncate.c new file mode 100644 index 000000000000..e312bf8bad9f --- /dev/null +++ b/fs/ufs/truncate.c @@ -0,0 +1,477 @@ +/* + * 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> + */ + +#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" + +#undef UFS_TRUNCATE_DEBUG + +#ifdef UFS_TRUNCATE_DEBUG +#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x; +#else +#define UFSD(x) +#endif + +/* + * 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) + +#define DATA_BUFFER_USED(bh) \ + (atomic_read(&bh->b_count)>1 || buffer_locked(bh)) + +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; + struct buffer_head * bh; + __fs32 * p; + unsigned frag1, frag2, frag3, frag4, block1, block2; + unsigned frag_to_free, free_count; + unsigned i, j, 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"); + frag1 = ufs_fragnum (frag1); + frag2 = ufs_fragnum (frag2); + for (j = frag1; j < frag2; j++) { + bh = sb_find_get_block (sb, tmp + j); + if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) { + retry = 1; + brelse (bh); + goto next1; + } + bforget (bh); + } + inode->i_blocks -= (frag2-frag1) << uspi->s_nspfshift; + mark_inode_dirty(inode); + ufs_free_fragments (inode, tmp + frag1, frag2 - frag1); + 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; + for (j = 0; j < uspi->s_fpb; j++) { + bh = sb_find_get_block(sb, tmp + j); + if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) { + retry = 1; + brelse (bh); + goto next2; + } + bforget (bh); + } + *p = 0; + inode->i_blocks -= uspi->s_nspb; + mark_inode_dirty(inode); + 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; + } +next2:; + } + + 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); + for (j = 0; j < frag4; j++) { + bh = sb_find_get_block (sb, tmp + j); + if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *p)) { + retry = 1; + brelse (bh); + goto next1; + } + bforget (bh); + } + *p = 0; + inode->i_blocks -= frag4 << uspi->s_nspfshift; + mark_inode_dirty(inode); + ufs_free_fragments (inode, tmp, frag4); + 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; + struct buffer_head * bh; + __fs32 * ind; + unsigned indirect_block, i, j, 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; + for (j = 0; j < uspi->s_fpb; j++) { + bh = sb_find_get_block(sb, tmp + j); + if ((bh && DATA_BUFFER_USED(bh)) || tmp != fs32_to_cpu(sb, *ind)) { + retry = 1; + brelse (bh); + goto next; + } + bforget (bh); + } + *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; + } + inode->i_blocks -= uspi->s_nspb; + mark_inode_dirty(inode); +next:; + } + + 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) { + if (ubh_max_bcount(ind_ubh) != 1) { + retry = 1; + } + else { + tmp = fs32_to_cpu(sb, *p); + *p = 0; + inode->i_blocks -= uspi->s_nspb; + mark_inode_dirty(inode); + ufs_free_blocks (inode, tmp, uspi->s_fpb); + ubh_bforget(ind_ubh); + ind_ubh = NULL; + } + } + if (IS_SYNC(inode) && ind_ubh && ubh_buffer_dirty(ind_ubh)) { + ubh_wait_on_buffer (ind_ubh); + ubh_ll_rw_block (WRITE, 1, &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) { + if (ubh_max_bcount(dind_bh) != 1) + retry = 1; + else { + tmp = fs32_to_cpu(sb, *p); + *p = 0; + inode->i_blocks -= uspi->s_nspb; + mark_inode_dirty(inode); + ufs_free_blocks (inode, tmp, uspi->s_fpb); + ubh_bforget(dind_bh); + dind_bh = NULL; + } + } + if (IS_SYNC(inode) && dind_bh && ubh_buffer_dirty(dind_bh)) { + ubh_wait_on_buffer (dind_bh); + ubh_ll_rw_block (WRITE, 1, &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) { + if (ubh_max_bcount(tind_bh) != 1) + retry = 1; + else { + tmp = fs32_to_cpu(sb, *p); + *p = 0; + inode->i_blocks -= uspi->s_nspb; + mark_inode_dirty(inode); + ufs_free_blocks (inode, tmp, uspi->s_fpb); + ubh_bforget(tind_bh); + tind_bh = NULL; + } + } + if (IS_SYNC(inode) && tind_bh && ubh_buffer_dirty(tind_bh)) { + ubh_wait_on_buffer (tind_bh); + ubh_ll_rw_block (WRITE, 1, &tind_bh); + ubh_wait_on_buffer (tind_bh); + } + ubh_brelse (tind_bh); + + UFSD(("EXIT\n")) + return retry; +} + +void ufs_truncate (struct inode * inode) +{ + struct ufs_inode_info *ufsi = UFS_I(inode); + struct super_block * sb; + struct ufs_sb_private_info * uspi; + struct buffer_head * bh; + unsigned offset; + int err, retry; + + UFSD(("ENTER\n")) + sb = inode->i_sb; + uspi = UFS_SB(sb)->s_uspi; + + if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) + return; + if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) + return; + 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(); + } + offset = inode->i_size & uspi->s_fshift; + if (offset) { + bh = ufs_bread (inode, inode->i_size >> uspi->s_fshift, 0, &err); + if (bh) { + memset (bh->b_data + offset, 0, uspi->s_fsize - offset); + mark_buffer_dirty (bh); + brelse (bh); + } + } + inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; + ufsi->i_lastfrag = DIRECT_FRAGMENT; + unlock_kernel(); + mark_inode_dirty(inode); + UFSD(("EXIT\n")) +} |