/* * truncate.c * * PURPOSE * Truncate handling routines for the OSTA-UDF(tm) filesystem. * * COPYRIGHT * This file is distributed under the terms of the GNU General Public * License (GPL). Copies of the GPL can be obtained from: * ftp://prep.ai.mit.edu/pub/gnu/GPL * Each contributing author retains all rights to their own work. * * (C) 1999-2004 Ben Fennema * (C) 1999 Stelias Computing Inc * * HISTORY * * 02/24/99 blf Created. * */ #include "udfdecl.h" #include <linux/fs.h> #include <linux/mm.h> #include <linux/udf_fs.h> #include <linux/buffer_head.h> #include "udf_i.h" #include "udf_sb.h" static void extent_trunc(struct inode * inode, kernel_lb_addr bloc, int extoffset, kernel_lb_addr eloc, int8_t etype, uint32_t elen, struct buffer_head *bh, uint32_t nelen) { kernel_lb_addr neloc = { 0, 0 }; int last_block = (elen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits; int first_block = (nelen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits; if (nelen) { if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) { udf_free_blocks(inode->i_sb, inode, eloc, 0, last_block); etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30); } else neloc = eloc; nelen = (etype << 30) | nelen; } if (elen != nelen) { udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0); if (last_block - first_block > 0) { if (etype == (EXT_RECORDED_ALLOCATED >> 30)) mark_inode_dirty(inode); if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) udf_free_blocks(inode->i_sb, inode, eloc, first_block, last_block - first_block); } } } void udf_discard_prealloc(struct inode * inode) { kernel_lb_addr bloc, eloc; uint32_t extoffset = 0, elen, nelen; uint64_t lbcount = 0; int8_t etype = -1, netype; struct buffer_head *bh = NULL; int adsize; if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB || inode->i_size == UDF_I_LENEXTENTS(inode)) { return; } if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT) adsize = sizeof(short_ad); else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG) adsize = sizeof(long_ad); else adsize = 0; bloc = UDF_I_LOCATION(inode); while ((netype = udf_next_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1) { etype = netype; lbcount += elen; if (lbcount > inode->i_size && lbcount - inode->i_size < inode->i_sb->s_blocksize) { nelen = elen - (lbcount - inode->i_size); extent_trunc(inode, bloc, extoffset-adsize, eloc, etype, elen, bh, nelen); lbcount = inode->i_size; } } if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) { extoffset -= adsize; lbcount -= elen; extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0); if (!bh) { UDF_I_LENALLOC(inode) = extoffset - udf_file_entry_alloc_offset(inode); mark_inode_dirty(inode); } else { struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data); aed->lengthAllocDescs = cpu_to_le32(extoffset - sizeof(struct allocExtDesc)); if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201) udf_update_tag(bh->b_data, extoffset); else udf_update_tag(bh->b_data, sizeof(struct allocExtDesc)); mark_buffer_dirty_inode(bh, inode); } } UDF_I_LENEXTENTS(inode) = lbcount; udf_release_data(bh); } void udf_truncate_extents(struct inode * inode) { kernel_lb_addr bloc, eloc, neloc = { 0, 0 }; uint32_t extoffset, elen, offset, nelen = 0, lelen = 0, lenalloc; int8_t etype; int first_block = inode->i_size >> inode->i_sb->s_blocksize_bits; struct buffer_head *bh = NULL; int adsize; if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT) adsize = sizeof(short_ad); else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG) adsize = sizeof(long_ad); else adsize = 0; etype = inode_bmap(inode, first_block, &bloc, &extoffset, &eloc, &elen, &offset, &bh); offset += (inode->i_size & (inode->i_sb->s_blocksize - 1)); if (etype != -1) { extoffset -= adsize; extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, offset); extoffset += adsize; if (offset) lenalloc = extoffset; else lenalloc = extoffset - adsize; if (!bh) lenalloc -= udf_file_entry_alloc_offset(inode); else lenalloc -= sizeof(struct allocExtDesc); while ((etype = udf_current_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 0)) != -1) { if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) { udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0); extoffset = 0; if (lelen) { if (!bh) BUG(); else memset(bh->b_data, 0x00, sizeof(struct allocExtDesc)); udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen); } else { if (!bh) { UDF_I_LENALLOC(inode) = lenalloc; mark_inode_dirty(inode); } else { struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data); aed->lengthAllocDescs = cpu_to_le32(lenalloc); if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201) udf_update_tag(bh->b_data, lenalloc + sizeof(struct allocExtDesc)); else udf_update_tag(bh->b_data, sizeof(struct allocExtDesc)); mark_buffer_dirty_inode(bh, inode); } } udf_release_data(bh); extoffset = sizeof(struct allocExtDesc); bloc = eloc; bh = udf_tread(inode->i_sb, udf_get_lb_pblock(inode->i_sb, bloc, 0)); if (elen) lelen = (elen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits; else lelen = 1; } else { extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0); extoffset += adsize; } } if (lelen) { if (!bh) BUG(); else memset(bh->b_data, 0x00, sizeof(struct allocExtDesc)); udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen); } else { if (!bh) { UDF_I_LENALLOC(inode) = lenalloc; mark_inode_dirty(inode); } else { struct allocExtDesc *aed = (struct allocExtDesc *)(bh->b_data); aed->lengthAllocDescs = cpu_to_le32(lenalloc); if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201) udf_update_tag(bh->b_data, lenalloc + sizeof(struct allocExtDesc)); else udf_update_tag(bh->b_data, sizeof(struct allocExtDesc)); mark_buffer_dirty_inode(bh, inode); } } } else if (inode->i_size) { if (offset) { extoffset -= adsize; etype = udf_next_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 1); if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30)) { extoffset -= adsize; elen = EXT_NOT_RECORDED_NOT_ALLOCATED | (elen + offset); udf_write_aext(inode, bloc, &extoffset, eloc, elen, bh, 0); } else if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) { kernel_lb_addr neloc = { 0, 0 }; extoffset -= adsize; nelen = EXT_NOT_RECORDED_NOT_ALLOCATED | ((elen + offset + inode->i_sb->s_blocksize - 1) & ~(inode->i_sb->s_blocksize - 1)); udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 1); udf_add_aext(inode, &bloc, &extoffset, eloc, (etype << 30) | elen, &bh, 1); } else { if (elen & (inode->i_sb->s_blocksize - 1)) { extoffset -= adsize; elen = EXT_RECORDED_ALLOCATED | ((elen + inode->i_sb->s_blocksize - 1) & ~(inode->i_sb->s_blocksize - 1)); udf_write_aext(inode, bloc, &extoffset, eloc, elen, bh, 1); } memset(&eloc, 0x00, sizeof(kernel_lb_addr)); elen = EXT_NOT_RECORDED_NOT_ALLOCATED | offset; udf_add_aext(inode, &bloc, &extoffset, eloc, elen, &bh, 1); } } } UDF_I_LENEXTENTS(inode) = inode->i_size; udf_release_data(bh); }