| /* |
| * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. |
| * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. |
| * |
| * This copyrighted material is made available to anyone wishing to use, |
| * modify, copy, or redistribute it subject to the terms and conditions |
| * of the GNU General Public License version 2. |
| */ |
| |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/spinlock.h> |
| #include <linux/completion.h> |
| #include <linux/buffer_head.h> |
| #include <linux/gfs2_ondisk.h> |
| #include <linux/crc32.h> |
| #include <linux/lm_interface.h> |
| |
| #include "gfs2.h" |
| #include "incore.h" |
| #include "bmap.h" |
| #include "glock.h" |
| #include "inode.h" |
| #include "meta_io.h" |
| #include "quota.h" |
| #include "rgrp.h" |
| #include "trans.h" |
| #include "dir.h" |
| #include "util.h" |
| #include "ops_address.h" |
| |
| /* This doesn't need to be that large as max 64 bit pointers in a 4k |
| * block is 512, so __u16 is fine for that. It saves stack space to |
| * keep it small. |
| */ |
| struct metapath { |
| __u16 mp_list[GFS2_MAX_META_HEIGHT]; |
| }; |
| |
| typedef int (*block_call_t) (struct gfs2_inode *ip, struct buffer_head *dibh, |
| struct buffer_head *bh, __be64 *top, |
| __be64 *bottom, unsigned int height, |
| void *data); |
| |
| struct strip_mine { |
| int sm_first; |
| unsigned int sm_height; |
| }; |
| |
| /** |
| * gfs2_unstuffer_page - unstuff a stuffed inode into a block cached by a page |
| * @ip: the inode |
| * @dibh: the dinode buffer |
| * @block: the block number that was allocated |
| * @private: any locked page held by the caller process |
| * |
| * Returns: errno |
| */ |
| |
| static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh, |
| u64 block, struct page *page) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| struct inode *inode = &ip->i_inode; |
| struct buffer_head *bh; |
| int release = 0; |
| |
| if (!page || page->index) { |
| page = grab_cache_page(inode->i_mapping, 0); |
| if (!page) |
| return -ENOMEM; |
| release = 1; |
| } |
| |
| if (!PageUptodate(page)) { |
| void *kaddr = kmap(page); |
| |
| memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), |
| ip->i_di.di_size); |
| memset(kaddr + ip->i_di.di_size, 0, |
| PAGE_CACHE_SIZE - ip->i_di.di_size); |
| kunmap(page); |
| |
| SetPageUptodate(page); |
| } |
| |
| if (!page_has_buffers(page)) |
| create_empty_buffers(page, 1 << inode->i_blkbits, |
| (1 << BH_Uptodate)); |
| |
| bh = page_buffers(page); |
| |
| if (!buffer_mapped(bh)) |
| map_bh(bh, inode->i_sb, block); |
| |
| set_buffer_uptodate(bh); |
| if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) |
| gfs2_trans_add_bh(ip->i_gl, bh, 0); |
| mark_buffer_dirty(bh); |
| |
| if (release) { |
| unlock_page(page); |
| page_cache_release(page); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big |
| * @ip: The GFS2 inode to unstuff |
| * @unstuffer: the routine that handles unstuffing a non-zero length file |
| * @private: private data for the unstuffer |
| * |
| * This routine unstuffs a dinode and returns it to a "normal" state such |
| * that the height can be grown in the traditional way. |
| * |
| * Returns: errno |
| */ |
| |
| int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page) |
| { |
| struct buffer_head *bh, *dibh; |
| struct gfs2_dinode *di; |
| u64 block = 0; |
| int isdir = gfs2_is_dir(ip); |
| int error; |
| |
| down_write(&ip->i_rw_mutex); |
| |
| error = gfs2_meta_inode_buffer(ip, &dibh); |
| if (error) |
| goto out; |
| |
| if (ip->i_di.di_size) { |
| /* Get a free block, fill it with the stuffed data, |
| and write it out to disk */ |
| |
| if (isdir) { |
| block = gfs2_alloc_meta(ip); |
| |
| error = gfs2_dir_get_new_buffer(ip, block, &bh); |
| if (error) |
| goto out_brelse; |
| gfs2_buffer_copy_tail(bh, sizeof(struct gfs2_meta_header), |
| dibh, sizeof(struct gfs2_dinode)); |
| brelse(bh); |
| } else { |
| block = gfs2_alloc_data(ip); |
| |
| error = gfs2_unstuffer_page(ip, dibh, block, page); |
| if (error) |
| goto out_brelse; |
| } |
| } |
| |
| /* Set up the pointer to the new block */ |
| |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| di = (struct gfs2_dinode *)dibh->b_data; |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); |
| |
| if (ip->i_di.di_size) { |
| *(__be64 *)(di + 1) = cpu_to_be64(block); |
| ip->i_di.di_blocks++; |
| di->di_blocks = cpu_to_be64(ip->i_di.di_blocks); |
| } |
| |
| ip->i_di.di_height = 1; |
| di->di_height = cpu_to_be16(1); |
| |
| out_brelse: |
| brelse(dibh); |
| out: |
| up_write(&ip->i_rw_mutex); |
| return error; |
| } |
| |
| /** |
| * calc_tree_height - Calculate the height of a metadata tree |
| * @ip: The GFS2 inode |
| * @size: The proposed size of the file |
| * |
| * Work out how tall a metadata tree needs to be in order to accommodate a |
| * file of a particular size. If size is less than the current size of |
| * the inode, then the current size of the inode is used instead of the |
| * supplied one. |
| * |
| * Returns: the height the tree should be |
| */ |
| |
| static unsigned int calc_tree_height(struct gfs2_inode *ip, u64 size) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| u64 *arr; |
| unsigned int max, height; |
| |
| if (ip->i_di.di_size > size) |
| size = ip->i_di.di_size; |
| |
| if (gfs2_is_dir(ip)) { |
| arr = sdp->sd_jheightsize; |
| max = sdp->sd_max_jheight; |
| } else { |
| arr = sdp->sd_heightsize; |
| max = sdp->sd_max_height; |
| } |
| |
| for (height = 0; height < max; height++) |
| if (arr[height] >= size) |
| break; |
| |
| return height; |
| } |
| |
| /** |
| * build_height - Build a metadata tree of the requested height |
| * @ip: The GFS2 inode |
| * @height: The height to build to |
| * |
| * |
| * Returns: errno |
| */ |
| |
| static int build_height(struct inode *inode, unsigned height) |
| { |
| struct gfs2_inode *ip = GFS2_I(inode); |
| unsigned new_height = height - ip->i_di.di_height; |
| struct buffer_head *dibh; |
| struct buffer_head *blocks[GFS2_MAX_META_HEIGHT]; |
| struct gfs2_dinode *di; |
| int error; |
| __be64 *bp; |
| u64 bn; |
| unsigned n; |
| |
| if (height <= ip->i_di.di_height) |
| return 0; |
| |
| error = gfs2_meta_inode_buffer(ip, &dibh); |
| if (error) |
| return error; |
| |
| for(n = 0; n < new_height; n++) { |
| bn = gfs2_alloc_meta(ip); |
| blocks[n] = gfs2_meta_new(ip->i_gl, bn); |
| gfs2_trans_add_bh(ip->i_gl, blocks[n], 1); |
| } |
| |
| n = 0; |
| bn = blocks[0]->b_blocknr; |
| if (new_height > 1) { |
| for(; n < new_height-1; n++) { |
| gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, |
| GFS2_FORMAT_IN); |
| gfs2_buffer_clear_tail(blocks[n], |
| sizeof(struct gfs2_meta_header)); |
| bp = (__be64 *)(blocks[n]->b_data + |
| sizeof(struct gfs2_meta_header)); |
| *bp = cpu_to_be64(blocks[n+1]->b_blocknr); |
| brelse(blocks[n]); |
| blocks[n] = NULL; |
| } |
| } |
| gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN); |
| gfs2_buffer_copy_tail(blocks[n], sizeof(struct gfs2_meta_header), |
| dibh, sizeof(struct gfs2_dinode)); |
| brelse(blocks[n]); |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| di = (struct gfs2_dinode *)dibh->b_data; |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); |
| *(__be64 *)(di + 1) = cpu_to_be64(bn); |
| ip->i_di.di_height += new_height; |
| ip->i_di.di_blocks += new_height; |
| di->di_height = cpu_to_be16(ip->i_di.di_height); |
| di->di_blocks = cpu_to_be64(ip->i_di.di_blocks); |
| brelse(dibh); |
| return error; |
| } |
| |
| /** |
| * find_metapath - Find path through the metadata tree |
| * @ip: The inode pointer |
| * @mp: The metapath to return the result in |
| * @block: The disk block to look up |
| * |
| * This routine returns a struct metapath structure that defines a path |
| * through the metadata of inode "ip" to get to block "block". |
| * |
| * Example: |
| * Given: "ip" is a height 3 file, "offset" is 101342453, and this is a |
| * filesystem with a blocksize of 4096. |
| * |
| * find_metapath() would return a struct metapath structure set to: |
| * mp_offset = 101342453, mp_height = 3, mp_list[0] = 0, mp_list[1] = 48, |
| * and mp_list[2] = 165. |
| * |
| * That means that in order to get to the block containing the byte at |
| * offset 101342453, we would load the indirect block pointed to by pointer |
| * 0 in the dinode. We would then load the indirect block pointed to by |
| * pointer 48 in that indirect block. We would then load the data block |
| * pointed to by pointer 165 in that indirect block. |
| * |
| * ---------------------------------------- |
| * | Dinode | | |
| * | | 4| |
| * | |0 1 2 3 4 5 9| |
| * | | 6| |
| * ---------------------------------------- |
| * | |
| * | |
| * V |
| * ---------------------------------------- |
| * | Indirect Block | |
| * | 5| |
| * | 4 4 4 4 4 5 5 1| |
| * |0 5 6 7 8 9 0 1 2| |
| * ---------------------------------------- |
| * | |
| * | |
| * V |
| * ---------------------------------------- |
| * | Indirect Block | |
| * | 1 1 1 1 1 5| |
| * | 6 6 6 6 6 1| |
| * |0 3 4 5 6 7 2| |
| * ---------------------------------------- |
| * | |
| * | |
| * V |
| * ---------------------------------------- |
| * | Data block containing offset | |
| * | 101342453 | |
| * | | |
| * | | |
| * ---------------------------------------- |
| * |
| */ |
| |
| static void find_metapath(struct gfs2_inode *ip, u64 block, |
| struct metapath *mp) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| u64 b = block; |
| unsigned int i; |
| |
| for (i = ip->i_di.di_height; i--;) |
| mp->mp_list[i] = do_div(b, sdp->sd_inptrs); |
| |
| } |
| |
| /** |
| * metapointer - Return pointer to start of metadata in a buffer |
| * @bh: The buffer |
| * @height: The metadata height (0 = dinode) |
| * @mp: The metapath |
| * |
| * Return a pointer to the block number of the next height of the metadata |
| * tree given a buffer containing the pointer to the current height of the |
| * metadata tree. |
| */ |
| |
| static inline __be64 *metapointer(struct buffer_head *bh, int *boundary, |
| unsigned int height, const struct metapath *mp) |
| { |
| unsigned int head_size = (height > 0) ? |
| sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode); |
| __be64 *ptr; |
| *boundary = 0; |
| ptr = ((__be64 *)(bh->b_data + head_size)) + mp->mp_list[height]; |
| if (ptr + 1 == (__be64 *)(bh->b_data + bh->b_size)) |
| *boundary = 1; |
| return ptr; |
| } |
| |
| /** |
| * lookup_block - Get the next metadata block in metadata tree |
| * @ip: The GFS2 inode |
| * @bh: Buffer containing the pointers to metadata blocks |
| * @height: The height of the tree (0 = dinode) |
| * @mp: The metapath |
| * @create: Non-zero if we may create a new meatdata block |
| * @new: Used to indicate if we did create a new metadata block |
| * @block: the returned disk block number |
| * |
| * Given a metatree, complete to a particular height, checks to see if the next |
| * height of the tree exists. If not the next height of the tree is created. |
| * The block number of the next height of the metadata tree is returned. |
| * |
| */ |
| |
| static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh, |
| unsigned int height, struct metapath *mp, int create, |
| int *new, u64 *block) |
| { |
| int boundary; |
| __be64 *ptr = metapointer(bh, &boundary, height, mp); |
| |
| if (*ptr) { |
| *block = be64_to_cpu(*ptr); |
| return boundary; |
| } |
| |
| *block = 0; |
| |
| if (!create) |
| return 0; |
| |
| if (height == ip->i_di.di_height - 1 && !gfs2_is_dir(ip)) |
| *block = gfs2_alloc_data(ip); |
| else |
| *block = gfs2_alloc_meta(ip); |
| |
| gfs2_trans_add_bh(ip->i_gl, bh, 1); |
| |
| *ptr = cpu_to_be64(*block); |
| ip->i_di.di_blocks++; |
| |
| *new = 1; |
| return 0; |
| } |
| |
| /** |
| * gfs2_block_pointers - Map a block from an inode to a disk block |
| * @inode: The inode |
| * @lblock: The logical block number |
| * @map_bh: The bh to be mapped |
| * @mp: metapath to use |
| * |
| * Find the block number on the current device which corresponds to an |
| * inode's block. If the block had to be created, "new" will be set. |
| * |
| * Returns: errno |
| */ |
| |
| static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create, |
| struct buffer_head *bh_map, struct metapath *mp) |
| { |
| struct gfs2_inode *ip = GFS2_I(inode); |
| struct gfs2_sbd *sdp = GFS2_SB(inode); |
| struct buffer_head *bh; |
| unsigned int bsize; |
| unsigned int height; |
| unsigned int end_of_metadata; |
| unsigned int x; |
| int error = 0; |
| int new = 0; |
| u64 dblock = 0; |
| int boundary; |
| unsigned int maxlen = bh_map->b_size >> inode->i_blkbits; |
| |
| BUG_ON(maxlen == 0); |
| |
| if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip))) |
| return 0; |
| |
| bsize = gfs2_is_dir(ip) ? sdp->sd_jbsize : sdp->sd_sb.sb_bsize; |
| |
| height = calc_tree_height(ip, (lblock + 1) * bsize); |
| if (ip->i_di.di_height < height) { |
| if (!create) |
| return 0; |
| |
| error = build_height(inode, height); |
| if (error) |
| return error; |
| } |
| |
| find_metapath(ip, lblock, mp); |
| end_of_metadata = ip->i_di.di_height - 1; |
| |
| error = gfs2_meta_inode_buffer(ip, &bh); |
| if (error) |
| return error; |
| |
| for (x = 0; x < end_of_metadata; x++) { |
| lookup_block(ip, bh, x, mp, create, &new, &dblock); |
| brelse(bh); |
| if (!dblock) |
| return 0; |
| |
| error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh); |
| if (error) |
| return error; |
| } |
| |
| boundary = lookup_block(ip, bh, end_of_metadata, mp, create, &new, &dblock); |
| clear_buffer_mapped(bh_map); |
| clear_buffer_new(bh_map); |
| clear_buffer_boundary(bh_map); |
| |
| if (dblock) { |
| map_bh(bh_map, inode->i_sb, dblock); |
| if (boundary) |
| set_buffer_boundary(bh); |
| if (new) { |
| struct buffer_head *dibh; |
| error = gfs2_meta_inode_buffer(ip, &dibh); |
| if (!error) { |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| gfs2_dinode_out(ip, dibh->b_data); |
| brelse(dibh); |
| } |
| set_buffer_new(bh_map); |
| goto out_brelse; |
| } |
| while(--maxlen && !buffer_boundary(bh_map)) { |
| u64 eblock; |
| |
| mp->mp_list[end_of_metadata]++; |
| boundary = lookup_block(ip, bh, end_of_metadata, mp, 0, &new, &eblock); |
| if (eblock != ++dblock) |
| break; |
| bh_map->b_size += (1 << inode->i_blkbits); |
| if (boundary) |
| set_buffer_boundary(bh_map); |
| } |
| } |
| out_brelse: |
| brelse(bh); |
| return 0; |
| } |
| |
| |
| static inline void bmap_lock(struct inode *inode, int create) |
| { |
| struct gfs2_inode *ip = GFS2_I(inode); |
| if (create) |
| down_write(&ip->i_rw_mutex); |
| else |
| down_read(&ip->i_rw_mutex); |
| } |
| |
| static inline void bmap_unlock(struct inode *inode, int create) |
| { |
| struct gfs2_inode *ip = GFS2_I(inode); |
| if (create) |
| up_write(&ip->i_rw_mutex); |
| else |
| up_read(&ip->i_rw_mutex); |
| } |
| |
| int gfs2_block_map(struct inode *inode, u64 lblock, int create, |
| struct buffer_head *bh) |
| { |
| struct metapath mp; |
| int ret; |
| |
| bmap_lock(inode, create); |
| ret = gfs2_block_pointers(inode, lblock, create, bh, &mp); |
| bmap_unlock(inode, create); |
| return ret; |
| } |
| |
| int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen) |
| { |
| struct metapath mp; |
| struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 }; |
| int ret; |
| int create = *new; |
| |
| BUG_ON(!extlen); |
| BUG_ON(!dblock); |
| BUG_ON(!new); |
| |
| bh.b_size = 1 << (inode->i_blkbits + 5); |
| bmap_lock(inode, create); |
| ret = gfs2_block_pointers(inode, lblock, create, &bh, &mp); |
| bmap_unlock(inode, create); |
| *extlen = bh.b_size >> inode->i_blkbits; |
| *dblock = bh.b_blocknr; |
| if (buffer_new(&bh)) |
| *new = 1; |
| else |
| *new = 0; |
| return ret; |
| } |
| |
| /** |
| * recursive_scan - recursively scan through the end of a file |
| * @ip: the inode |
| * @dibh: the dinode buffer |
| * @mp: the path through the metadata to the point to start |
| * @height: the height the recursion is at |
| * @block: the indirect block to look at |
| * @first: 1 if this is the first block |
| * @bc: the call to make for each piece of metadata |
| * @data: data opaque to this function to pass to @bc |
| * |
| * When this is first called @height and @block should be zero and |
| * @first should be 1. |
| * |
| * Returns: errno |
| */ |
| |
| static int recursive_scan(struct gfs2_inode *ip, struct buffer_head *dibh, |
| struct metapath *mp, unsigned int height, |
| u64 block, int first, block_call_t bc, |
| void *data) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| struct buffer_head *bh = NULL; |
| __be64 *top, *bottom; |
| u64 bn; |
| int error; |
| int mh_size = sizeof(struct gfs2_meta_header); |
| |
| if (!height) { |
| error = gfs2_meta_inode_buffer(ip, &bh); |
| if (error) |
| return error; |
| dibh = bh; |
| |
| top = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + mp->mp_list[0]; |
| bottom = (__be64 *)(bh->b_data + sizeof(struct gfs2_dinode)) + sdp->sd_diptrs; |
| } else { |
| error = gfs2_meta_indirect_buffer(ip, height, block, 0, &bh); |
| if (error) |
| return error; |
| |
| top = (__be64 *)(bh->b_data + mh_size) + |
| (first ? mp->mp_list[height] : 0); |
| |
| bottom = (__be64 *)(bh->b_data + mh_size) + sdp->sd_inptrs; |
| } |
| |
| error = bc(ip, dibh, bh, top, bottom, height, data); |
| if (error) |
| goto out; |
| |
| if (height < ip->i_di.di_height - 1) |
| for (; top < bottom; top++, first = 0) { |
| if (!*top) |
| continue; |
| |
| bn = be64_to_cpu(*top); |
| |
| error = recursive_scan(ip, dibh, mp, height + 1, bn, |
| first, bc, data); |
| if (error) |
| break; |
| } |
| |
| out: |
| brelse(bh); |
| return error; |
| } |
| |
| /** |
| * do_strip - Look for a layer a particular layer of the file and strip it off |
| * @ip: the inode |
| * @dibh: the dinode buffer |
| * @bh: A buffer of pointers |
| * @top: The first pointer in the buffer |
| * @bottom: One more than the last pointer |
| * @height: the height this buffer is at |
| * @data: a pointer to a struct strip_mine |
| * |
| * Returns: errno |
| */ |
| |
| static int do_strip(struct gfs2_inode *ip, struct buffer_head *dibh, |
| struct buffer_head *bh, __be64 *top, __be64 *bottom, |
| unsigned int height, void *data) |
| { |
| struct strip_mine *sm = data; |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| struct gfs2_rgrp_list rlist; |
| u64 bn, bstart; |
| u32 blen; |
| __be64 *p; |
| unsigned int rg_blocks = 0; |
| int metadata; |
| unsigned int revokes = 0; |
| int x; |
| int error; |
| |
| if (!*top) |
| sm->sm_first = 0; |
| |
| if (height != sm->sm_height) |
| return 0; |
| |
| if (sm->sm_first) { |
| top++; |
| sm->sm_first = 0; |
| } |
| |
| metadata = (height != ip->i_di.di_height - 1); |
| if (metadata) |
| revokes = (height) ? sdp->sd_inptrs : sdp->sd_diptrs; |
| |
| error = gfs2_rindex_hold(sdp, &ip->i_alloc.al_ri_gh); |
| if (error) |
| return error; |
| |
| memset(&rlist, 0, sizeof(struct gfs2_rgrp_list)); |
| bstart = 0; |
| blen = 0; |
| |
| for (p = top; p < bottom; p++) { |
| if (!*p) |
| continue; |
| |
| bn = be64_to_cpu(*p); |
| |
| if (bstart + blen == bn) |
| blen++; |
| else { |
| if (bstart) |
| gfs2_rlist_add(sdp, &rlist, bstart); |
| |
| bstart = bn; |
| blen = 1; |
| } |
| } |
| |
| if (bstart) |
| gfs2_rlist_add(sdp, &rlist, bstart); |
| else |
| goto out; /* Nothing to do */ |
| |
| gfs2_rlist_alloc(&rlist, LM_ST_EXCLUSIVE, 0); |
| |
| for (x = 0; x < rlist.rl_rgrps; x++) { |
| struct gfs2_rgrpd *rgd; |
| rgd = rlist.rl_ghs[x].gh_gl->gl_object; |
| rg_blocks += rgd->rd_ri.ri_length; |
| } |
| |
| error = gfs2_glock_nq_m(rlist.rl_rgrps, rlist.rl_ghs); |
| if (error) |
| goto out_rlist; |
| |
| error = gfs2_trans_begin(sdp, rg_blocks + RES_DINODE + |
| RES_INDIRECT + RES_STATFS + RES_QUOTA, |
| revokes); |
| if (error) |
| goto out_rg_gunlock; |
| |
| down_write(&ip->i_rw_mutex); |
| |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| gfs2_trans_add_bh(ip->i_gl, bh, 1); |
| |
| bstart = 0; |
| blen = 0; |
| |
| for (p = top; p < bottom; p++) { |
| if (!*p) |
| continue; |
| |
| bn = be64_to_cpu(*p); |
| |
| if (bstart + blen == bn) |
| blen++; |
| else { |
| if (bstart) { |
| if (metadata) |
| gfs2_free_meta(ip, bstart, blen); |
| else |
| gfs2_free_data(ip, bstart, blen); |
| } |
| |
| bstart = bn; |
| blen = 1; |
| } |
| |
| *p = 0; |
| if (!ip->i_di.di_blocks) |
| gfs2_consist_inode(ip); |
| ip->i_di.di_blocks--; |
| } |
| if (bstart) { |
| if (metadata) |
| gfs2_free_meta(ip, bstart, blen); |
| else |
| gfs2_free_data(ip, bstart, blen); |
| } |
| |
| ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds(); |
| |
| gfs2_dinode_out(ip, dibh->b_data); |
| |
| up_write(&ip->i_rw_mutex); |
| |
| gfs2_trans_end(sdp); |
| |
| out_rg_gunlock: |
| gfs2_glock_dq_m(rlist.rl_rgrps, rlist.rl_ghs); |
| out_rlist: |
| gfs2_rlist_free(&rlist); |
| out: |
| gfs2_glock_dq_uninit(&ip->i_alloc.al_ri_gh); |
| return error; |
| } |
| |
| /** |
| * do_grow - Make a file look bigger than it is |
| * @ip: the inode |
| * @size: the size to set the file to |
| * |
| * Called with an exclusive lock on @ip. |
| * |
| * Returns: errno |
| */ |
| |
| static int do_grow(struct gfs2_inode *ip, u64 size) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| struct gfs2_alloc *al; |
| struct buffer_head *dibh; |
| unsigned int h; |
| int error; |
| |
| al = gfs2_alloc_get(ip); |
| |
| error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); |
| if (error) |
| goto out; |
| |
| error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid); |
| if (error) |
| goto out_gunlock_q; |
| |
| al->al_requested = sdp->sd_max_height + RES_DATA; |
| |
| error = gfs2_inplace_reserve(ip); |
| if (error) |
| goto out_gunlock_q; |
| |
| error = gfs2_trans_begin(sdp, |
| sdp->sd_max_height + al->al_rgd->rd_ri.ri_length + |
| RES_JDATA + RES_DINODE + RES_STATFS + RES_QUOTA, 0); |
| if (error) |
| goto out_ipres; |
| |
| if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) { |
| if (gfs2_is_stuffed(ip)) { |
| error = gfs2_unstuff_dinode(ip, NULL); |
| if (error) |
| goto out_end_trans; |
| } |
| |
| h = calc_tree_height(ip, size); |
| if (ip->i_di.di_height < h) { |
| down_write(&ip->i_rw_mutex); |
| error = build_height(&ip->i_inode, h); |
| up_write(&ip->i_rw_mutex); |
| if (error) |
| goto out_end_trans; |
| } |
| } |
| |
| ip->i_di.di_size = size; |
| ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds(); |
| |
| error = gfs2_meta_inode_buffer(ip, &dibh); |
| if (error) |
| goto out_end_trans; |
| |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| gfs2_dinode_out(ip, dibh->b_data); |
| brelse(dibh); |
| |
| out_end_trans: |
| gfs2_trans_end(sdp); |
| out_ipres: |
| gfs2_inplace_release(ip); |
| out_gunlock_q: |
| gfs2_quota_unlock(ip); |
| out: |
| gfs2_alloc_put(ip); |
| return error; |
| } |
| |
| |
| /** |
| * gfs2_block_truncate_page - Deal with zeroing out data for truncate |
| * |
| * This is partly borrowed from ext3. |
| */ |
| static int gfs2_block_truncate_page(struct address_space *mapping) |
| { |
| struct inode *inode = mapping->host; |
| struct gfs2_inode *ip = GFS2_I(inode); |
| struct gfs2_sbd *sdp = GFS2_SB(inode); |
| loff_t from = inode->i_size; |
| unsigned long index = from >> PAGE_CACHE_SHIFT; |
| unsigned offset = from & (PAGE_CACHE_SIZE-1); |
| unsigned blocksize, iblock, length, pos; |
| struct buffer_head *bh; |
| struct page *page; |
| void *kaddr; |
| int err; |
| |
| page = grab_cache_page(mapping, index); |
| if (!page) |
| return 0; |
| |
| blocksize = inode->i_sb->s_blocksize; |
| length = blocksize - (offset & (blocksize - 1)); |
| iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); |
| |
| if (!page_has_buffers(page)) |
| create_empty_buffers(page, blocksize, 0); |
| |
| /* Find the buffer that contains "offset" */ |
| bh = page_buffers(page); |
| pos = blocksize; |
| while (offset >= pos) { |
| bh = bh->b_this_page; |
| iblock++; |
| pos += blocksize; |
| } |
| |
| err = 0; |
| |
| if (!buffer_mapped(bh)) { |
| gfs2_get_block(inode, iblock, bh, 0); |
| /* unmapped? It's a hole - nothing to do */ |
| if (!buffer_mapped(bh)) |
| goto unlock; |
| } |
| |
| /* Ok, it's mapped. Make sure it's up-to-date */ |
| if (PageUptodate(page)) |
| set_buffer_uptodate(bh); |
| |
| if (!buffer_uptodate(bh)) { |
| err = -EIO; |
| ll_rw_block(READ, 1, &bh); |
| wait_on_buffer(bh); |
| /* Uhhuh. Read error. Complain and punt. */ |
| if (!buffer_uptodate(bh)) |
| goto unlock; |
| } |
| |
| if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) |
| gfs2_trans_add_bh(ip->i_gl, bh, 0); |
| |
| kaddr = kmap_atomic(page, KM_USER0); |
| memset(kaddr + offset, 0, length); |
| flush_dcache_page(page); |
| kunmap_atomic(kaddr, KM_USER0); |
| |
| unlock: |
| unlock_page(page); |
| page_cache_release(page); |
| return err; |
| } |
| |
| static int trunc_start(struct gfs2_inode *ip, u64 size) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| struct buffer_head *dibh; |
| int journaled = gfs2_is_jdata(ip); |
| int error; |
| |
| error = gfs2_trans_begin(sdp, |
| RES_DINODE + (journaled ? RES_JDATA : 0), 0); |
| if (error) |
| return error; |
| |
| error = gfs2_meta_inode_buffer(ip, &dibh); |
| if (error) |
| goto out; |
| |
| if (gfs2_is_stuffed(ip)) { |
| ip->i_di.di_size = size; |
| ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds(); |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| gfs2_dinode_out(ip, dibh->b_data); |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + size); |
| error = 1; |
| |
| } else { |
| if (size & (u64)(sdp->sd_sb.sb_bsize - 1)) |
| error = gfs2_block_truncate_page(ip->i_inode.i_mapping); |
| |
| if (!error) { |
| ip->i_di.di_size = size; |
| ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds(); |
| ip->i_di.di_flags |= GFS2_DIF_TRUNC_IN_PROG; |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| gfs2_dinode_out(ip, dibh->b_data); |
| } |
| } |
| |
| brelse(dibh); |
| |
| out: |
| gfs2_trans_end(sdp); |
| return error; |
| } |
| |
| static int trunc_dealloc(struct gfs2_inode *ip, u64 size) |
| { |
| unsigned int height = ip->i_di.di_height; |
| u64 lblock; |
| struct metapath mp; |
| int error; |
| |
| if (!size) |
| lblock = 0; |
| else |
| lblock = (size - 1) >> GFS2_SB(&ip->i_inode)->sd_sb.sb_bsize_shift; |
| |
| find_metapath(ip, lblock, &mp); |
| gfs2_alloc_get(ip); |
| |
| error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); |
| if (error) |
| goto out; |
| |
| while (height--) { |
| struct strip_mine sm; |
| sm.sm_first = !!size; |
| sm.sm_height = height; |
| |
| error = recursive_scan(ip, NULL, &mp, 0, 0, 1, do_strip, &sm); |
| if (error) |
| break; |
| } |
| |
| gfs2_quota_unhold(ip); |
| |
| out: |
| gfs2_alloc_put(ip); |
| return error; |
| } |
| |
| static int trunc_end(struct gfs2_inode *ip) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| struct buffer_head *dibh; |
| int error; |
| |
| error = gfs2_trans_begin(sdp, RES_DINODE, 0); |
| if (error) |
| return error; |
| |
| down_write(&ip->i_rw_mutex); |
| |
| error = gfs2_meta_inode_buffer(ip, &dibh); |
| if (error) |
| goto out; |
| |
| if (!ip->i_di.di_size) { |
| ip->i_di.di_height = 0; |
| ip->i_di.di_goal_meta = |
| ip->i_di.di_goal_data = |
| ip->i_num.no_addr; |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); |
| } |
| ip->i_inode.i_mtime.tv_sec = ip->i_inode.i_ctime.tv_sec = get_seconds(); |
| ip->i_di.di_flags &= ~GFS2_DIF_TRUNC_IN_PROG; |
| |
| gfs2_trans_add_bh(ip->i_gl, dibh, 1); |
| gfs2_dinode_out(ip, dibh->b_data); |
| brelse(dibh); |
| |
| out: |
| up_write(&ip->i_rw_mutex); |
| gfs2_trans_end(sdp); |
| return error; |
| } |
| |
| /** |
| * do_shrink - make a file smaller |
| * @ip: the inode |
| * @size: the size to make the file |
| * @truncator: function to truncate the last partial block |
| * |
| * Called with an exclusive lock on @ip. |
| * |
| * Returns: errno |
| */ |
| |
| static int do_shrink(struct gfs2_inode *ip, u64 size) |
| { |
| int error; |
| |
| error = trunc_start(ip, size); |
| if (error < 0) |
| return error; |
| if (error > 0) |
| return 0; |
| |
| error = trunc_dealloc(ip, size); |
| if (!error) |
| error = trunc_end(ip); |
| |
| return error; |
| } |
| |
| /** |
| * gfs2_truncatei - make a file a given size |
| * @ip: the inode |
| * @size: the size to make the file |
| * @truncator: function to truncate the last partial block |
| * |
| * The file size can grow, shrink, or stay the same size. |
| * |
| * Returns: errno |
| */ |
| |
| int gfs2_truncatei(struct gfs2_inode *ip, u64 size) |
| { |
| int error; |
| |
| if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), S_ISREG(ip->i_inode.i_mode))) |
| return -EINVAL; |
| |
| if (size > ip->i_di.di_size) |
| error = do_grow(ip, size); |
| else |
| error = do_shrink(ip, size); |
| |
| return error; |
| } |
| |
| int gfs2_truncatei_resume(struct gfs2_inode *ip) |
| { |
| int error; |
| error = trunc_dealloc(ip, ip->i_di.di_size); |
| if (!error) |
| error = trunc_end(ip); |
| return error; |
| } |
| |
| int gfs2_file_dealloc(struct gfs2_inode *ip) |
| { |
| return trunc_dealloc(ip, 0); |
| } |
| |
| /** |
| * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file |
| * @ip: the file |
| * @len: the number of bytes to be written to the file |
| * @data_blocks: returns the number of data blocks required |
| * @ind_blocks: returns the number of indirect blocks required |
| * |
| */ |
| |
| void gfs2_write_calc_reserv(struct gfs2_inode *ip, unsigned int len, |
| unsigned int *data_blocks, unsigned int *ind_blocks) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| unsigned int tmp; |
| |
| if (gfs2_is_dir(ip)) { |
| *data_blocks = DIV_ROUND_UP(len, sdp->sd_jbsize) + 2; |
| *ind_blocks = 3 * (sdp->sd_max_jheight - 1); |
| } else { |
| *data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3; |
| *ind_blocks = 3 * (sdp->sd_max_height - 1); |
| } |
| |
| for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) { |
| tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); |
| *ind_blocks += tmp; |
| } |
| } |
| |
| /** |
| * gfs2_write_alloc_required - figure out if a write will require an allocation |
| * @ip: the file being written to |
| * @offset: the offset to write to |
| * @len: the number of bytes being written |
| * @alloc_required: set to 1 if an alloc is required, 0 otherwise |
| * |
| * Returns: errno |
| */ |
| |
| int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset, |
| unsigned int len, int *alloc_required) |
| { |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); |
| u64 lblock, lblock_stop, dblock; |
| u32 extlen; |
| int new = 0; |
| int error = 0; |
| |
| *alloc_required = 0; |
| |
| if (!len) |
| return 0; |
| |
| if (gfs2_is_stuffed(ip)) { |
| if (offset + len > |
| sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) |
| *alloc_required = 1; |
| return 0; |
| } |
| |
| if (gfs2_is_dir(ip)) { |
| unsigned int bsize = sdp->sd_jbsize; |
| lblock = offset; |
| do_div(lblock, bsize); |
| lblock_stop = offset + len + bsize - 1; |
| do_div(lblock_stop, bsize); |
| } else { |
| unsigned int shift = sdp->sd_sb.sb_bsize_shift; |
| lblock = offset >> shift; |
| lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift; |
| } |
| |
| for (; lblock < lblock_stop; lblock += extlen) { |
| error = gfs2_extent_map(&ip->i_inode, lblock, &new, &dblock, &extlen); |
| if (error) |
| return error; |
| |
| if (!dblock) { |
| *alloc_required = 1; |
| return 0; |
| } |
| } |
| |
| return 0; |
| } |
| |