[net-next-2.6.git] / fs / udf / truncate.c

/*
 * truncate.c
 *
 * PURPOSE
 *	Truncate handling routines for the OSTA-UDF(tm) filesystem.
 *
 * CONTACTS
 *	E-mail regarding any portion of the Linux UDF file system should be
 *	directed to the development team mailing list (run by majordomo):
 *		linux_udf@hpesjro.fc.hp.com
 *
 * 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);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* truncate.c
	3	*
	4	* PURPOSE
	5	* Truncate handling routines for the OSTA-UDF(tm) filesystem.
	6	*
	7	* CONTACTS
	8	* E-mail regarding any portion of the Linux UDF file system should be
	9	* directed to the development team mailing list (run by majordomo):
	10	* linux_udf@hpesjro.fc.hp.com
	11	*
	12	* COPYRIGHT
	13	* This file is distributed under the terms of the GNU General Public
	14	* License (GPL). Copies of the GPL can be obtained from:
	15	* ftp://prep.ai.mit.edu/pub/gnu/GPL
	16	* Each contributing author retains all rights to their own work.
	17	*
	18	* (C) 1999-2004 Ben Fennema
	19	* (C) 1999 Stelias Computing Inc
	20	*
	21	* HISTORY
	22	*
	23	* 02/24/99 blf Created.
	24	*
	25	*/
	26
	27	#include "udfdecl.h"
	28	#include <linux/fs.h>
	29	#include <linux/mm.h>
	30	#include <linux/udf_fs.h>
	31	#include <linux/buffer_head.h>
	32
	33	#include "udf_i.h"
	34	#include "udf_sb.h"
	35
	36	static void extent_trunc(struct inode * inode, kernel_lb_addr bloc, int extoffset,
	37	kernel_lb_addr eloc, int8_t etype, uint32_t elen, struct buffer_head *bh, uint32_t nelen)
	38	{
	39	kernel_lb_addr neloc = { 0, 0 };
	40	int last_block = (elen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
	41	int first_block = (nelen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
	42
	43	if (nelen)
	44	{
	45	if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
	46	{
	47	udf_free_blocks(inode->i_sb, inode, eloc, 0, last_block);
	48	etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
	49	}
	50	else
	51	neloc = eloc;
	52	nelen = (etype << 30) \| nelen;
	53	}
	54
	55	if (elen != nelen)
	56	{
	57	udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0);
	58	if (last_block - first_block > 0)
	59	{
	60	if (etype == (EXT_RECORDED_ALLOCATED >> 30))
	61	mark_inode_dirty(inode);
	62
	63	if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
	64	udf_free_blocks(inode->i_sb, inode, eloc, first_block, last_block - first_block);
65	}
66	}
67	}
68
69	void udf_discard_prealloc(struct inode * inode)
70	{
71	kernel_lb_addr bloc, eloc;
72	uint32_t extoffset = 0, elen, nelen;
73	uint64_t lbcount = 0;
74	int8_t etype = -1, netype;
75	struct buffer_head *bh = NULL;
76	int adsize;
77
78	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB \|\|
79	inode->i_size == UDF_I_LENEXTENTS(inode))
80	{
81	return;
82	}
83
84	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
85	adsize = sizeof(short_ad);
86	else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
87	adsize = sizeof(long_ad);
88	else
89	adsize = 0;
90
91	bloc = UDF_I_LOCATION(inode);
92
93	while ((netype = udf_next_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 1)) != -1)
94	{
95	etype = netype;
96	lbcount += elen;
97	if (lbcount > inode->i_size && lbcount - inode->i_size < inode->i_sb->s_blocksize)
98	{
99	nelen = elen - (lbcount - inode->i_size);
100	extent_trunc(inode, bloc, extoffset-adsize, eloc, etype, elen, bh, nelen);
101	lbcount = inode->i_size;
102	}
103	}
104	if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
105	{
106	extoffset -= adsize;
107	lbcount -= elen;
108	extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0);
109	if (!bh)
110	{
111	UDF_I_LENALLOC(inode) = extoffset - udf_file_entry_alloc_offset(inode);
112	mark_inode_dirty(inode);
113	}
114	else
115	{
116	struct allocExtDesc aed = (struct allocExtDesc )(bh->b_data);
117	aed->lengthAllocDescs = cpu_to_le32(extoffset - sizeof(struct allocExtDesc));
118	if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) \|\| UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
119	udf_update_tag(bh->b_data, extoffset);
120	else
121	udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
122	mark_buffer_dirty_inode(bh, inode);
123	}
124	}
125	UDF_I_LENEXTENTS(inode) = lbcount;
126
127	udf_release_data(bh);
128	}
129
130	void udf_truncate_extents(struct inode * inode)
131	{
132	kernel_lb_addr bloc, eloc, neloc = { 0, 0 };
133	uint32_t extoffset, elen, offset, nelen = 0, lelen = 0, lenalloc;
134	int8_t etype;
135	int first_block = inode->i_size >> inode->i_sb->s_blocksize_bits;
136	struct buffer_head *bh = NULL;
137	int adsize;
138
139	if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
140	adsize = sizeof(short_ad);
141	else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
142	adsize = sizeof(long_ad);
143	else
144	adsize = 0;
145
146	etype = inode_bmap(inode, first_block, &bloc, &extoffset, &eloc, &elen, &offset, &bh);
147	offset += (inode->i_size & (inode->i_sb->s_blocksize - 1));
148	if (etype != -1)
149	{
150	extoffset -= adsize;
151	extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, offset);
152	extoffset += adsize;
153
154	if (offset)
155	lenalloc = extoffset;
156	else
157	lenalloc = extoffset - adsize;
158
159	if (!bh)
160	lenalloc -= udf_file_entry_alloc_offset(inode);
161	else
162	lenalloc -= sizeof(struct allocExtDesc);
163
164	while ((etype = udf_current_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 0)) != -1)
165	{
166	if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30))
167	{
168	udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 0);
169	extoffset = 0;
170	if (lelen)
171	{
172	if (!bh)
173	BUG();
174	else
175	memset(bh->b_data, 0x00, sizeof(struct allocExtDesc));
176	udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen);
177	}
178	else
179	{
180	if (!bh)
181	{
182	UDF_I_LENALLOC(inode) = lenalloc;
183	mark_inode_dirty(inode);
184	}
185	else
186	{
187	struct allocExtDesc aed = (struct allocExtDesc )(bh->b_data);
188	aed->lengthAllocDescs = cpu_to_le32(lenalloc);
189	if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) \|\| UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
190	udf_update_tag(bh->b_data, lenalloc +
191	sizeof(struct allocExtDesc));
192	else
193	udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
194	mark_buffer_dirty_inode(bh, inode);
195	}
196	}
197
198	udf_release_data(bh);
199	extoffset = sizeof(struct allocExtDesc);
200	bloc = eloc;
201	bh = udf_tread(inode->i_sb, udf_get_lb_pblock(inode->i_sb, bloc, 0));
202	if (elen)
203	lelen = (elen + inode->i_sb->s_blocksize - 1) >>
204	inode->i_sb->s_blocksize_bits;
205	else
206	lelen = 1;
207	}
208	else
209	{
210	extent_trunc(inode, bloc, extoffset, eloc, etype, elen, bh, 0);
211	extoffset += adsize;
212	}
213	}
214
215	if (lelen)
216	{
217	if (!bh)
218	BUG();
219	else
220	memset(bh->b_data, 0x00, sizeof(struct allocExtDesc));
221	udf_free_blocks(inode->i_sb, inode, bloc, 0, lelen);
222	}
223	else
224	{
225	if (!bh)
226	{
227	UDF_I_LENALLOC(inode) = lenalloc;
228	mark_inode_dirty(inode);
229	}
230	else
231	{
232	struct allocExtDesc aed = (struct allocExtDesc )(bh->b_data);
233	aed->lengthAllocDescs = cpu_to_le32(lenalloc);
234	if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) \|\| UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
235	udf_update_tag(bh->b_data, lenalloc +
236	sizeof(struct allocExtDesc));
237	else
238	udf_update_tag(bh->b_data, sizeof(struct allocExtDesc));
239	mark_buffer_dirty_inode(bh, inode);
240	}
241	}
242	}
243	else if (inode->i_size)
244	{
245	if (offset)
246	{
247	extoffset -= adsize;
248	etype = udf_next_aext(inode, &bloc, &extoffset, &eloc, &elen, &bh, 1);
249	if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
250	{
251	extoffset -= adsize;
252	elen = EXT_NOT_RECORDED_NOT_ALLOCATED \| (elen + offset);
253	udf_write_aext(inode, bloc, &extoffset, eloc, elen, bh, 0);
254	}
255	else if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
256	{
257	kernel_lb_addr neloc = { 0, 0 };
258	extoffset -= adsize;
259	nelen = EXT_NOT_RECORDED_NOT_ALLOCATED \|
260	((elen + offset + inode->i_sb->s_blocksize - 1) &
261	~(inode->i_sb->s_blocksize - 1));
262	udf_write_aext(inode, bloc, &extoffset, neloc, nelen, bh, 1);
263	udf_add_aext(inode, &bloc, &extoffset, eloc, (etype << 30) \| elen, &bh, 1);
264	}
265	else
266	{
267	if (elen & (inode->i_sb->s_blocksize - 1))
268	{
269	extoffset -= adsize;
270	elen = EXT_RECORDED_ALLOCATED \|
271	((elen + inode->i_sb->s_blocksize - 1) &
272	~(inode->i_sb->s_blocksize - 1));
273	udf_write_aext(inode, bloc, &extoffset, eloc, elen, bh, 1);
274	}
275	memset(&eloc, 0x00, sizeof(kernel_lb_addr));
276	elen = EXT_NOT_RECORDED_NOT_ALLOCATED \| offset;
277	udf_add_aext(inode, &bloc, &extoffset, eloc, elen, &bh, 1);
278	}
279	}
280	}
281	UDF_I_LENEXTENTS(inode) = inode->i_size;
282
283	udf_release_data(bh);
284	}