| /* | |
| * 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/spinlock.h> | |
| #include <linux/completion.h> | |
| #include <linux/buffer_head.h> | |
| #include <linux/blkdev.h> | |
| #include <linux/gfs2_ondisk.h> | |
| #include <linux/crc32.h> | |
| #include <linux/iomap.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 "log.h" | |
| #include "super.h" | |
| #include "trans.h" | |
| #include "dir.h" | |
| #include "util.h" | |
| #include "trace_gfs2.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 { | |
| struct buffer_head *mp_bh[GFS2_MAX_META_HEIGHT]; | |
| __u16 mp_list[GFS2_MAX_META_HEIGHT]; | |
| int mp_fheight; /* find_metapath height */ | |
| int mp_aheight; /* actual height (lookup 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 | |
| * @page: The (optional) page. This is looked up if @page is NULL | |
| * | |
| * Returns: errno | |
| */ | |
| static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh, | |
| u64 block, struct page *page) | |
| { | |
| struct inode *inode = &ip->i_inode; | |
| struct buffer_head *bh; | |
| int release = 0; | |
| if (!page || page->index) { | |
| page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS); | |
| if (!page) | |
| return -ENOMEM; | |
| release = 1; | |
| } | |
| if (!PageUptodate(page)) { | |
| void *kaddr = kmap(page); | |
| u64 dsize = i_size_read(inode); | |
| if (dsize > (dibh->b_size - sizeof(struct gfs2_dinode))) | |
| dsize = dibh->b_size - sizeof(struct gfs2_dinode); | |
| memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize); | |
| memset(kaddr + dsize, 0, PAGE_SIZE - dsize); | |
| kunmap(page); | |
| SetPageUptodate(page); | |
| } | |
| if (!page_has_buffers(page)) | |
| create_empty_buffers(page, BIT(inode->i_blkbits), | |
| BIT(BH_Uptodate)); | |
| bh = page_buffers(page); | |
| if (!buffer_mapped(bh)) | |
| map_bh(bh, inode->i_sb, block); | |
| set_buffer_uptodate(bh); | |
| if (!gfs2_is_jdata(ip)) | |
| mark_buffer_dirty(bh); | |
| if (!gfs2_is_writeback(ip)) | |
| gfs2_trans_add_data(ip->i_gl, bh); | |
| if (release) { | |
| unlock_page(page); | |
| put_page(page); | |
| } | |
| return 0; | |
| } | |
| /** | |
| * gfs2_unstuff_dinode - Unstuff a dinode when the data has grown too big | |
| * @ip: The GFS2 inode to unstuff | |
| * @page: The (optional) page. This is looked up if the @page is NULL | |
| * | |
| * 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 (i_size_read(&ip->i_inode)) { | |
| /* Get a free block, fill it with the stuffed data, | |
| and write it out to disk */ | |
| unsigned int n = 1; | |
| error = gfs2_alloc_blocks(ip, &block, &n, 0, NULL); | |
| if (error) | |
| goto out_brelse; | |
| if (isdir) { | |
| gfs2_trans_add_unrevoke(GFS2_SB(&ip->i_inode), block, 1); | |
| 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 { | |
| error = gfs2_unstuffer_page(ip, dibh, block, page); | |
| if (error) | |
| goto out_brelse; | |
| } | |
| } | |
| /* Set up the pointer to the new block */ | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| di = (struct gfs2_dinode *)dibh->b_data; | |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); | |
| if (i_size_read(&ip->i_inode)) { | |
| *(__be64 *)(di + 1) = cpu_to_be64(block); | |
| gfs2_add_inode_blocks(&ip->i_inode, 1); | |
| di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode)); | |
| } | |
| ip->i_height = 1; | |
| di->di_height = cpu_to_be16(1); | |
| out_brelse: | |
| brelse(dibh); | |
| out: | |
| up_write(&ip->i_rw_mutex); | |
| return error; | |
| } | |
| /** | |
| * find_metapath - Find path through the metadata tree | |
| * @sdp: The superblock | |
| * @mp: The metapath to return the result in | |
| * @block: The disk block to look up | |
| * @height: The pre-calculated height of the metadata tree | |
| * | |
| * 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(const struct gfs2_sbd *sdp, u64 block, | |
| struct metapath *mp, unsigned int height) | |
| { | |
| unsigned int i; | |
| mp->mp_fheight = height; | |
| for (i = height; i--;) | |
| mp->mp_list[i] = do_div(block, sdp->sd_inptrs); | |
| } | |
| static inline unsigned int metapath_branch_start(const struct metapath *mp) | |
| { | |
| if (mp->mp_list[0] == 0) | |
| return 2; | |
| return 1; | |
| } | |
| /** | |
| * metaptr1 - Return the first possible metadata pointer in a metapath buffer | |
| * @height: The metadata height (0 = dinode) | |
| * @mp: The metapath | |
| */ | |
| static inline __be64 *metaptr1(unsigned int height, const struct metapath *mp) | |
| { | |
| struct buffer_head *bh = mp->mp_bh[height]; | |
| if (height == 0) | |
| return ((__be64 *)(bh->b_data + sizeof(struct gfs2_dinode))); | |
| return ((__be64 *)(bh->b_data + sizeof(struct gfs2_meta_header))); | |
| } | |
| /** | |
| * metapointer - Return pointer to start of metadata in a 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(unsigned int height, const struct metapath *mp) | |
| { | |
| __be64 *p = metaptr1(height, mp); | |
| return p + mp->mp_list[height]; | |
| } | |
| static void gfs2_metapath_ra(struct gfs2_glock *gl, | |
| const struct buffer_head *bh, const __be64 *pos) | |
| { | |
| struct buffer_head *rabh; | |
| const __be64 *endp = (const __be64 *)(bh->b_data + bh->b_size); | |
| const __be64 *t; | |
| for (t = pos; t < endp; t++) { | |
| if (!*t) | |
| continue; | |
| rabh = gfs2_getbuf(gl, be64_to_cpu(*t), CREATE); | |
| if (trylock_buffer(rabh)) { | |
| if (!buffer_uptodate(rabh)) { | |
| rabh->b_end_io = end_buffer_read_sync; | |
| submit_bh(REQ_OP_READ, | |
| REQ_RAHEAD | REQ_META | REQ_PRIO, | |
| rabh); | |
| continue; | |
| } | |
| unlock_buffer(rabh); | |
| } | |
| brelse(rabh); | |
| } | |
| } | |
| /** | |
| * lookup_mp_height - helper function for lookup_metapath | |
| * @ip: the inode | |
| * @mp: the metapath | |
| * @h: the height which needs looking up | |
| */ | |
| static int lookup_mp_height(struct gfs2_inode *ip, struct metapath *mp, int h) | |
| { | |
| __be64 *ptr = metapointer(h, mp); | |
| u64 dblock = be64_to_cpu(*ptr); | |
| if (!dblock) | |
| return h + 1; | |
| return gfs2_meta_indirect_buffer(ip, h + 1, dblock, &mp->mp_bh[h + 1]); | |
| } | |
| /** | |
| * lookup_metapath - Walk the metadata tree to a specific point | |
| * @ip: The inode | |
| * @mp: The metapath | |
| * | |
| * Assumes that the inode's buffer has already been looked up and | |
| * hooked onto mp->mp_bh[0] and that the metapath has been initialised | |
| * by find_metapath(). | |
| * | |
| * If this function encounters part of the tree which has not been | |
| * allocated, it returns the current height of the tree at the point | |
| * at which it found the unallocated block. Blocks which are found are | |
| * added to the mp->mp_bh[] list. | |
| * | |
| * Returns: error or height of metadata tree | |
| */ | |
| static int lookup_metapath(struct gfs2_inode *ip, struct metapath *mp) | |
| { | |
| unsigned int end_of_metadata = ip->i_height - 1; | |
| unsigned int x; | |
| int ret; | |
| for (x = 0; x < end_of_metadata; x++) { | |
| ret = lookup_mp_height(ip, mp, x); | |
| if (ret) | |
| goto out; | |
| } | |
| ret = ip->i_height; | |
| out: | |
| mp->mp_aheight = ret; | |
| return ret; | |
| } | |
| /** | |
| * fillup_metapath - fill up buffers for the metadata path to a specific height | |
| * @ip: The inode | |
| * @mp: The metapath | |
| * @h: The height to which it should be mapped | |
| * | |
| * Similar to lookup_metapath, but does lookups for a range of heights | |
| * | |
| * Returns: error or height of metadata tree | |
| */ | |
| static int fillup_metapath(struct gfs2_inode *ip, struct metapath *mp, int h) | |
| { | |
| unsigned int start_h = h - 1; | |
| int ret; | |
| if (h) { | |
| /* find the first buffer we need to look up. */ | |
| while (start_h > 0 && mp->mp_bh[start_h] == NULL) | |
| start_h--; | |
| for (; start_h < h; start_h++) { | |
| ret = lookup_mp_height(ip, mp, start_h); | |
| if (ret) | |
| return ret; | |
| } | |
| } | |
| return ip->i_height; | |
| } | |
| static inline void release_metapath(struct metapath *mp) | |
| { | |
| int i; | |
| for (i = 0; i < GFS2_MAX_META_HEIGHT; i++) { | |
| if (mp->mp_bh[i] == NULL) | |
| break; | |
| brelse(mp->mp_bh[i]); | |
| } | |
| } | |
| /** | |
| * gfs2_extent_length - Returns length of an extent of blocks | |
| * @start: Start of the buffer | |
| * @len: Length of the buffer in bytes | |
| * @ptr: Current position in the buffer | |
| * @limit: Max extent length to return (0 = unlimited) | |
| * @eob: Set to 1 if we hit "end of block" | |
| * | |
| * If the first block is zero (unallocated) it will return the number of | |
| * unallocated blocks in the extent, otherwise it will return the number | |
| * of contiguous blocks in the extent. | |
| * | |
| * Returns: The length of the extent (minimum of one block) | |
| */ | |
| static inline unsigned int gfs2_extent_length(void *start, unsigned int len, __be64 *ptr, size_t limit, int *eob) | |
| { | |
| const __be64 *end = (start + len); | |
| const __be64 *first = ptr; | |
| u64 d = be64_to_cpu(*ptr); | |
| *eob = 0; | |
| do { | |
| ptr++; | |
| if (ptr >= end) | |
| break; | |
| if (limit && --limit == 0) | |
| break; | |
| if (d) | |
| d++; | |
| } while(be64_to_cpu(*ptr) == d); | |
| if (ptr >= end) | |
| *eob = 1; | |
| return (ptr - first); | |
| } | |
| static inline void bmap_lock(struct gfs2_inode *ip, int create) | |
| { | |
| if (create) | |
| down_write(&ip->i_rw_mutex); | |
| else | |
| down_read(&ip->i_rw_mutex); | |
| } | |
| static inline void bmap_unlock(struct gfs2_inode *ip, int create) | |
| { | |
| if (create) | |
| up_write(&ip->i_rw_mutex); | |
| else | |
| up_read(&ip->i_rw_mutex); | |
| } | |
| static inline __be64 *gfs2_indirect_init(struct metapath *mp, | |
| struct gfs2_glock *gl, unsigned int i, | |
| unsigned offset, u64 bn) | |
| { | |
| __be64 *ptr = (__be64 *)(mp->mp_bh[i - 1]->b_data + | |
| ((i > 1) ? sizeof(struct gfs2_meta_header) : | |
| sizeof(struct gfs2_dinode))); | |
| BUG_ON(i < 1); | |
| BUG_ON(mp->mp_bh[i] != NULL); | |
| mp->mp_bh[i] = gfs2_meta_new(gl, bn); | |
| gfs2_trans_add_meta(gl, mp->mp_bh[i]); | |
| gfs2_metatype_set(mp->mp_bh[i], GFS2_METATYPE_IN, GFS2_FORMAT_IN); | |
| gfs2_buffer_clear_tail(mp->mp_bh[i], sizeof(struct gfs2_meta_header)); | |
| ptr += offset; | |
| *ptr = cpu_to_be64(bn); | |
| return ptr; | |
| } | |
| enum alloc_state { | |
| ALLOC_DATA = 0, | |
| ALLOC_GROW_DEPTH = 1, | |
| ALLOC_GROW_HEIGHT = 2, | |
| /* ALLOC_UNSTUFF = 3, TBD and rather complicated */ | |
| }; | |
| static inline unsigned int hptrs(struct gfs2_sbd *sdp, const unsigned int hgt) | |
| { | |
| if (hgt) | |
| return sdp->sd_inptrs; | |
| return sdp->sd_diptrs; | |
| } | |
| /** | |
| * gfs2_bmap_alloc - Build a metadata tree of the requested height | |
| * @inode: The GFS2 inode | |
| * @lblock: The logical starting block of the extent | |
| * @bh_map: This is used to return the mapping details | |
| * @zero_new: True if newly allocated blocks should be zeroed | |
| * @mp: The metapath, with proper height information calculated | |
| * @maxlen: The max number of data blocks to alloc | |
| * @dblock: Pointer to return the resulting new block | |
| * @dblks: Pointer to return the number of blocks allocated | |
| * | |
| * In this routine we may have to alloc: | |
| * i) Indirect blocks to grow the metadata tree height | |
| * ii) Indirect blocks to fill in lower part of the metadata tree | |
| * iii) Data blocks | |
| * | |
| * The function is in two parts. The first part works out the total | |
| * number of blocks which we need. The second part does the actual | |
| * allocation asking for an extent at a time (if enough contiguous free | |
| * blocks are available, there will only be one request per bmap call) | |
| * and uses the state machine to initialise the blocks in order. | |
| * | |
| * Returns: errno on error | |
| */ | |
| static int gfs2_iomap_alloc(struct inode *inode, struct iomap *iomap, | |
| unsigned flags, struct metapath *mp) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| struct gfs2_sbd *sdp = GFS2_SB(inode); | |
| struct super_block *sb = sdp->sd_vfs; | |
| struct buffer_head *dibh = mp->mp_bh[0]; | |
| u64 bn; | |
| unsigned n, i, blks, alloced = 0, iblks = 0, branch_start = 0; | |
| unsigned dblks = 0; | |
| unsigned ptrs_per_blk; | |
| const unsigned end_of_metadata = mp->mp_fheight - 1; | |
| int ret; | |
| enum alloc_state state; | |
| __be64 *ptr; | |
| __be64 zero_bn = 0; | |
| size_t maxlen = iomap->length >> inode->i_blkbits; | |
| BUG_ON(mp->mp_aheight < 1); | |
| BUG_ON(dibh == NULL); | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| if (mp->mp_fheight == mp->mp_aheight) { | |
| struct buffer_head *bh; | |
| int eob; | |
| /* Bottom indirect block exists, find unalloced extent size */ | |
| ptr = metapointer(end_of_metadata, mp); | |
| bh = mp->mp_bh[end_of_metadata]; | |
| dblks = gfs2_extent_length(bh->b_data, bh->b_size, ptr, | |
| maxlen, &eob); | |
| BUG_ON(dblks < 1); | |
| state = ALLOC_DATA; | |
| } else { | |
| /* Need to allocate indirect blocks */ | |
| ptrs_per_blk = mp->mp_fheight > 1 ? sdp->sd_inptrs : | |
| sdp->sd_diptrs; | |
| dblks = min(maxlen, (size_t)(ptrs_per_blk - | |
| mp->mp_list[end_of_metadata])); | |
| if (mp->mp_fheight == ip->i_height) { | |
| /* Writing into existing tree, extend tree down */ | |
| iblks = mp->mp_fheight - mp->mp_aheight; | |
| state = ALLOC_GROW_DEPTH; | |
| } else { | |
| /* Building up tree height */ | |
| state = ALLOC_GROW_HEIGHT; | |
| iblks = mp->mp_fheight - ip->i_height; | |
| branch_start = metapath_branch_start(mp); | |
| iblks += (mp->mp_fheight - branch_start); | |
| } | |
| } | |
| /* start of the second part of the function (state machine) */ | |
| blks = dblks + iblks; | |
| i = mp->mp_aheight; | |
| do { | |
| int error; | |
| n = blks - alloced; | |
| error = gfs2_alloc_blocks(ip, &bn, &n, 0, NULL); | |
| if (error) | |
| return error; | |
| alloced += n; | |
| if (state != ALLOC_DATA || gfs2_is_jdata(ip)) | |
| gfs2_trans_add_unrevoke(sdp, bn, n); | |
| switch (state) { | |
| /* Growing height of tree */ | |
| case ALLOC_GROW_HEIGHT: | |
| if (i == 1) { | |
| ptr = (__be64 *)(dibh->b_data + | |
| sizeof(struct gfs2_dinode)); | |
| zero_bn = *ptr; | |
| } | |
| for (; i - 1 < mp->mp_fheight - ip->i_height && n > 0; | |
| i++, n--) | |
| gfs2_indirect_init(mp, ip->i_gl, i, 0, bn++); | |
| if (i - 1 == mp->mp_fheight - ip->i_height) { | |
| i--; | |
| gfs2_buffer_copy_tail(mp->mp_bh[i], | |
| sizeof(struct gfs2_meta_header), | |
| dibh, sizeof(struct gfs2_dinode)); | |
| gfs2_buffer_clear_tail(dibh, | |
| sizeof(struct gfs2_dinode) + | |
| sizeof(__be64)); | |
| ptr = (__be64 *)(mp->mp_bh[i]->b_data + | |
| sizeof(struct gfs2_meta_header)); | |
| *ptr = zero_bn; | |
| state = ALLOC_GROW_DEPTH; | |
| for(i = branch_start; i < mp->mp_fheight; i++) { | |
| if (mp->mp_bh[i] == NULL) | |
| break; | |
| brelse(mp->mp_bh[i]); | |
| mp->mp_bh[i] = NULL; | |
| } | |
| i = branch_start; | |
| } | |
| if (n == 0) | |
| break; | |
| /* Branching from existing tree */ | |
| case ALLOC_GROW_DEPTH: | |
| if (i > 1 && i < mp->mp_fheight) | |
| gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[i-1]); | |
| for (; i < mp->mp_fheight && n > 0; i++, n--) | |
| gfs2_indirect_init(mp, ip->i_gl, i, | |
| mp->mp_list[i-1], bn++); | |
| if (i == mp->mp_fheight) | |
| state = ALLOC_DATA; | |
| if (n == 0) | |
| break; | |
| /* Tree complete, adding data blocks */ | |
| case ALLOC_DATA: | |
| BUG_ON(n > dblks); | |
| BUG_ON(mp->mp_bh[end_of_metadata] == NULL); | |
| gfs2_trans_add_meta(ip->i_gl, mp->mp_bh[end_of_metadata]); | |
| dblks = n; | |
| ptr = metapointer(end_of_metadata, mp); | |
| iomap->addr = bn << inode->i_blkbits; | |
| iomap->flags |= IOMAP_F_NEW; | |
| while (n-- > 0) | |
| *ptr++ = cpu_to_be64(bn++); | |
| if (flags & IOMAP_ZERO) { | |
| ret = sb_issue_zeroout(sb, iomap->addr >> inode->i_blkbits, | |
| dblks, GFP_NOFS); | |
| if (ret) { | |
| fs_err(sdp, | |
| "Failed to zero data buffers\n"); | |
| flags &= ~IOMAP_ZERO; | |
| } | |
| } | |
| break; | |
| } | |
| } while (iomap->addr == IOMAP_NULL_ADDR); | |
| iomap->length = (u64)dblks << inode->i_blkbits; | |
| ip->i_height = mp->mp_fheight; | |
| gfs2_add_inode_blocks(&ip->i_inode, alloced); | |
| gfs2_dinode_out(ip, mp->mp_bh[0]->b_data); | |
| return 0; | |
| } | |
| /** | |
| * hole_size - figure out the size of a hole | |
| * @inode: The inode | |
| * @lblock: The logical starting block number | |
| * @mp: The metapath | |
| * | |
| * Returns: The hole size in bytes | |
| * | |
| */ | |
| static u64 hole_size(struct inode *inode, sector_t lblock, struct metapath *mp) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| struct gfs2_sbd *sdp = GFS2_SB(inode); | |
| struct metapath mp_eof; | |
| u64 factor = 1; | |
| int hgt; | |
| u64 holesz = 0; | |
| const __be64 *first, *end, *ptr; | |
| const struct buffer_head *bh; | |
| u64 lblock_stop = (i_size_read(inode) - 1) >> inode->i_blkbits; | |
| int zeroptrs; | |
| bool done = false; | |
| /* Get another metapath, to the very last byte */ | |
| find_metapath(sdp, lblock_stop, &mp_eof, ip->i_height); | |
| for (hgt = ip->i_height - 1; hgt >= 0 && !done; hgt--) { | |
| bh = mp->mp_bh[hgt]; | |
| if (bh) { | |
| zeroptrs = 0; | |
| first = metapointer(hgt, mp); | |
| end = (const __be64 *)(bh->b_data + bh->b_size); | |
| for (ptr = first; ptr < end; ptr++) { | |
| if (*ptr) { | |
| done = true; | |
| break; | |
| } else { | |
| zeroptrs++; | |
| } | |
| } | |
| } else { | |
| zeroptrs = sdp->sd_inptrs; | |
| } | |
| if (factor * zeroptrs >= lblock_stop - lblock + 1) { | |
| holesz = lblock_stop - lblock + 1; | |
| break; | |
| } | |
| holesz += factor * zeroptrs; | |
| factor *= sdp->sd_inptrs; | |
| if (hgt && (mp->mp_list[hgt - 1] < mp_eof.mp_list[hgt - 1])) | |
| (mp->mp_list[hgt - 1])++; | |
| } | |
| return holesz << inode->i_blkbits; | |
| } | |
| static void gfs2_stuffed_iomap(struct inode *inode, struct iomap *iomap) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| iomap->addr = (ip->i_no_addr << inode->i_blkbits) + | |
| sizeof(struct gfs2_dinode); | |
| iomap->offset = 0; | |
| iomap->length = i_size_read(inode); | |
| iomap->type = IOMAP_MAPPED; | |
| iomap->flags = IOMAP_F_DATA_INLINE; | |
| } | |
| /** | |
| * gfs2_iomap_begin - Map blocks from an inode to disk blocks | |
| * @inode: The inode | |
| * @pos: Starting position in bytes | |
| * @length: Length to map, in bytes | |
| * @flags: iomap flags | |
| * @iomap: The iomap structure | |
| * | |
| * Returns: errno | |
| */ | |
| int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length, | |
| unsigned flags, struct iomap *iomap) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| struct gfs2_sbd *sdp = GFS2_SB(inode); | |
| struct metapath mp = { .mp_aheight = 1, }; | |
| unsigned int factor = sdp->sd_sb.sb_bsize; | |
| const u64 *arr = sdp->sd_heightsize; | |
| __be64 *ptr; | |
| sector_t lblock; | |
| sector_t lend; | |
| int ret; | |
| int eob; | |
| unsigned int len; | |
| struct buffer_head *bh; | |
| u8 height; | |
| trace_gfs2_iomap_start(ip, pos, length, flags); | |
| if (!length) { | |
| ret = -EINVAL; | |
| goto out; | |
| } | |
| if ((flags & IOMAP_REPORT) && gfs2_is_stuffed(ip)) { | |
| gfs2_stuffed_iomap(inode, iomap); | |
| if (pos >= iomap->length) | |
| return -ENOENT; | |
| ret = 0; | |
| goto out; | |
| } | |
| lblock = pos >> inode->i_blkbits; | |
| lend = (pos + length + sdp->sd_sb.sb_bsize - 1) >> inode->i_blkbits; | |
| iomap->offset = lblock << inode->i_blkbits; | |
| iomap->addr = IOMAP_NULL_ADDR; | |
| iomap->type = IOMAP_HOLE; | |
| iomap->length = (u64)(lend - lblock) << inode->i_blkbits; | |
| iomap->flags = IOMAP_F_MERGED; | |
| bmap_lock(ip, 0); | |
| /* | |
| * Directory data blocks have a struct gfs2_meta_header header, so the | |
| * remaining size is smaller than the filesystem block size. Logical | |
| * block numbers for directories are in units of this remaining size! | |
| */ | |
| if (gfs2_is_dir(ip)) { | |
| factor = sdp->sd_jbsize; | |
| arr = sdp->sd_jheightsize; | |
| } | |
| ret = gfs2_meta_inode_buffer(ip, &mp.mp_bh[0]); | |
| if (ret) | |
| goto out_release; | |
| height = ip->i_height; | |
| while ((lblock + 1) * factor > arr[height]) | |
| height++; | |
| find_metapath(sdp, lblock, &mp, height); | |
| if (height > ip->i_height || gfs2_is_stuffed(ip)) | |
| goto do_alloc; | |
| ret = lookup_metapath(ip, &mp); | |
| if (ret < 0) | |
| goto out_release; | |
| if (mp.mp_aheight != ip->i_height) | |
| goto do_alloc; | |
| ptr = metapointer(ip->i_height - 1, &mp); | |
| if (*ptr == 0) | |
| goto do_alloc; | |
| iomap->type = IOMAP_MAPPED; | |
| iomap->addr = be64_to_cpu(*ptr) << inode->i_blkbits; | |
| bh = mp.mp_bh[ip->i_height - 1]; | |
| len = gfs2_extent_length(bh->b_data, bh->b_size, ptr, lend - lblock, &eob); | |
| if (eob) | |
| iomap->flags |= IOMAP_F_BOUNDARY; | |
| iomap->length = (u64)len << inode->i_blkbits; | |
| ret = 0; | |
| out_release: | |
| release_metapath(&mp); | |
| bmap_unlock(ip, 0); | |
| out: | |
| trace_gfs2_iomap_end(ip, iomap, ret); | |
| return ret; | |
| do_alloc: | |
| if (!(flags & IOMAP_WRITE)) { | |
| if (pos >= i_size_read(inode)) { | |
| ret = -ENOENT; | |
| goto out_release; | |
| } | |
| ret = 0; | |
| iomap->length = hole_size(inode, lblock, &mp); | |
| goto out_release; | |
| } | |
| ret = gfs2_iomap_alloc(inode, iomap, flags, &mp); | |
| goto out_release; | |
| } | |
| /** | |
| * gfs2_block_map - Map a block from an inode to a disk block | |
| * @inode: The inode | |
| * @lblock: The logical block number | |
| * @bh_map: The bh to be mapped | |
| * @create: True if its ok to alloc blocks to satify the request | |
| * | |
| * Sets buffer_mapped() if successful, sets buffer_boundary() if a | |
| * read of metadata will be required before the next block can be | |
| * mapped. Sets buffer_new() if new blocks were allocated. | |
| * | |
| * Returns: errno | |
| */ | |
| int gfs2_block_map(struct inode *inode, sector_t lblock, | |
| struct buffer_head *bh_map, int create) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| struct iomap iomap; | |
| int ret, flags = 0; | |
| clear_buffer_mapped(bh_map); | |
| clear_buffer_new(bh_map); | |
| clear_buffer_boundary(bh_map); | |
| trace_gfs2_bmap(ip, bh_map, lblock, create, 1); | |
| if (create) | |
| flags |= IOMAP_WRITE; | |
| if (buffer_zeronew(bh_map)) | |
| flags |= IOMAP_ZERO; | |
| ret = gfs2_iomap_begin(inode, (loff_t)lblock << inode->i_blkbits, | |
| bh_map->b_size, flags, &iomap); | |
| if (ret) { | |
| if (!create && ret == -ENOENT) { | |
| /* Return unmapped buffer beyond the end of file. */ | |
| ret = 0; | |
| } | |
| goto out; | |
| } | |
| if (iomap.length > bh_map->b_size) { | |
| iomap.length = bh_map->b_size; | |
| iomap.flags &= ~IOMAP_F_BOUNDARY; | |
| } | |
| if (iomap.addr != IOMAP_NULL_ADDR) | |
| map_bh(bh_map, inode->i_sb, iomap.addr >> inode->i_blkbits); | |
| bh_map->b_size = iomap.length; | |
| if (iomap.flags & IOMAP_F_BOUNDARY) | |
| set_buffer_boundary(bh_map); | |
| if (iomap.flags & IOMAP_F_NEW) | |
| set_buffer_new(bh_map); | |
| out: | |
| trace_gfs2_bmap(ip, bh_map, lblock, create, ret); | |
| return ret; | |
| } | |
| /* | |
| * Deprecated: do not use in new code | |
| */ | |
| int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen) | |
| { | |
| 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 = BIT(inode->i_blkbits + (create ? 0 : 5)); | |
| ret = gfs2_block_map(inode, lblock, &bh, create); | |
| *extlen = bh.b_size >> inode->i_blkbits; | |
| *dblock = bh.b_blocknr; | |
| if (buffer_new(&bh)) | |
| *new = 1; | |
| else | |
| *new = 0; | |
| return ret; | |
| } | |
| /** | |
| * 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, loff_t from) | |
| { | |
| struct inode *inode = mapping->host; | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| unsigned long index = from >> PAGE_SHIFT; | |
| unsigned offset = from & (PAGE_SIZE-1); | |
| unsigned blocksize, iblock, length, pos; | |
| struct buffer_head *bh; | |
| struct page *page; | |
| int err; | |
| page = find_or_create_page(mapping, index, GFP_NOFS); | |
| if (!page) | |
| return 0; | |
| blocksize = inode->i_sb->s_blocksize; | |
| length = blocksize - (offset & (blocksize - 1)); | |
| iblock = index << (PAGE_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_block_map(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(REQ_OP_READ, 0, 1, &bh); | |
| wait_on_buffer(bh); | |
| /* Uhhuh. Read error. Complain and punt. */ | |
| if (!buffer_uptodate(bh)) | |
| goto unlock; | |
| err = 0; | |
| } | |
| if (!gfs2_is_writeback(ip)) | |
| gfs2_trans_add_data(ip->i_gl, bh); | |
| zero_user(page, offset, length); | |
| mark_buffer_dirty(bh); | |
| unlock: | |
| unlock_page(page); | |
| put_page(page); | |
| return err; | |
| } | |
| #define GFS2_JTRUNC_REVOKES 8192 | |
| /** | |
| * gfs2_journaled_truncate - Wrapper for truncate_pagecache for jdata files | |
| * @inode: The inode being truncated | |
| * @oldsize: The original (larger) size | |
| * @newsize: The new smaller size | |
| * | |
| * With jdata files, we have to journal a revoke for each block which is | |
| * truncated. As a result, we need to split this into separate transactions | |
| * if the number of pages being truncated gets too large. | |
| */ | |
| static int gfs2_journaled_truncate(struct inode *inode, u64 oldsize, u64 newsize) | |
| { | |
| struct gfs2_sbd *sdp = GFS2_SB(inode); | |
| u64 max_chunk = GFS2_JTRUNC_REVOKES * sdp->sd_vfs->s_blocksize; | |
| u64 chunk; | |
| int error; | |
| while (oldsize != newsize) { | |
| chunk = oldsize - newsize; | |
| if (chunk > max_chunk) | |
| chunk = max_chunk; | |
| truncate_pagecache(inode, oldsize - chunk); | |
| oldsize -= chunk; | |
| gfs2_trans_end(sdp); | |
| error = gfs2_trans_begin(sdp, RES_DINODE, GFS2_JTRUNC_REVOKES); | |
| if (error) | |
| return error; | |
| } | |
| return 0; | |
| } | |
| static int trunc_start(struct inode *inode, u64 oldsize, u64 newsize) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| struct gfs2_sbd *sdp = GFS2_SB(inode); | |
| struct address_space *mapping = inode->i_mapping; | |
| struct buffer_head *dibh; | |
| int journaled = gfs2_is_jdata(ip); | |
| int error; | |
| if (journaled) | |
| error = gfs2_trans_begin(sdp, RES_DINODE + RES_JDATA, GFS2_JTRUNC_REVOKES); | |
| else | |
| error = gfs2_trans_begin(sdp, RES_DINODE, 0); | |
| if (error) | |
| return error; | |
| error = gfs2_meta_inode_buffer(ip, &dibh); | |
| if (error) | |
| goto out; | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| if (gfs2_is_stuffed(ip)) { | |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode) + newsize); | |
| } else { | |
| if (newsize & (u64)(sdp->sd_sb.sb_bsize - 1)) { | |
| error = gfs2_block_truncate_page(mapping, newsize); | |
| if (error) | |
| goto out_brelse; | |
| } | |
| ip->i_diskflags |= GFS2_DIF_TRUNC_IN_PROG; | |
| } | |
| i_size_write(inode, newsize); | |
| ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode); | |
| gfs2_dinode_out(ip, dibh->b_data); | |
| if (journaled) | |
| error = gfs2_journaled_truncate(inode, oldsize, newsize); | |
| else | |
| truncate_pagecache(inode, newsize); | |
| if (error) { | |
| brelse(dibh); | |
| return error; | |
| } | |
| out_brelse: | |
| brelse(dibh); | |
| out: | |
| gfs2_trans_end(sdp); | |
| return error; | |
| } | |
| /** | |
| * sweep_bh_for_rgrps - find an rgrp in a meta buffer and free blocks therein | |
| * @ip: inode | |
| * @rg_gh: holder of resource group glock | |
| * @mp: current metapath fully populated with buffers | |
| * @btotal: place to keep count of total blocks freed | |
| * @hgt: height we're processing | |
| * @first: true if this is the first call to this function for this height | |
| * | |
| * We sweep a metadata buffer (provided by the metapath) for blocks we need to | |
| * free, and free them all. However, we do it one rgrp at a time. If this | |
| * block has references to multiple rgrps, we break it into individual | |
| * transactions. This allows other processes to use the rgrps while we're | |
| * focused on a single one, for better concurrency / performance. | |
| * At every transaction boundary, we rewrite the inode into the journal. | |
| * That way the bitmaps are kept consistent with the inode and we can recover | |
| * if we're interrupted by power-outages. | |
| * | |
| * Returns: 0, or return code if an error occurred. | |
| * *btotal has the total number of blocks freed | |
| */ | |
| static int sweep_bh_for_rgrps(struct gfs2_inode *ip, struct gfs2_holder *rd_gh, | |
| const struct metapath *mp, u32 *btotal, int hgt, | |
| bool preserve1) | |
| { | |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); | |
| struct gfs2_rgrpd *rgd; | |
| struct gfs2_trans *tr; | |
| struct buffer_head *bh = mp->mp_bh[hgt]; | |
| __be64 *top, *bottom, *p; | |
| int blks_outside_rgrp; | |
| u64 bn, bstart, isize_blks; | |
| s64 blen; /* needs to be s64 or gfs2_add_inode_blocks breaks */ | |
| int meta = ((hgt != ip->i_height - 1) ? 1 : 0); | |
| int ret = 0; | |
| bool buf_in_tr = false; /* buffer was added to transaction */ | |
| if (gfs2_metatype_check(sdp, bh, | |
| (hgt ? GFS2_METATYPE_IN : GFS2_METATYPE_DI))) | |
| return -EIO; | |
| more_rgrps: | |
| blks_outside_rgrp = 0; | |
| bstart = 0; | |
| blen = 0; | |
| top = metapointer(hgt, mp); /* first ptr from metapath */ | |
| /* If we're keeping some data at the truncation point, we've got to | |
| preserve the metadata tree by adding 1 to the starting metapath. */ | |
| if (preserve1) | |
| top++; | |
| bottom = (__be64 *)(bh->b_data + bh->b_size); | |
| for (p = top; p < bottom; p++) { | |
| if (!*p) | |
| continue; | |
| bn = be64_to_cpu(*p); | |
| if (gfs2_holder_initialized(rd_gh)) { | |
| rgd = gfs2_glock2rgrp(rd_gh->gh_gl); | |
| gfs2_assert_withdraw(sdp, | |
| gfs2_glock_is_locked_by_me(rd_gh->gh_gl)); | |
| } else { | |
| rgd = gfs2_blk2rgrpd(sdp, bn, false); | |
| ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, | |
| 0, rd_gh); | |
| if (ret) | |
| goto out; | |
| /* Must be done with the rgrp glock held: */ | |
| if (gfs2_rs_active(&ip->i_res) && | |
| rgd == ip->i_res.rs_rbm.rgd) | |
| gfs2_rs_deltree(&ip->i_res); | |
| } | |
| if (!rgrp_contains_block(rgd, bn)) { | |
| blks_outside_rgrp++; | |
| continue; | |
| } | |
| /* The size of our transactions will be unknown until we | |
| actually process all the metadata blocks that relate to | |
| the rgrp. So we estimate. We know it can't be more than | |
| the dinode's i_blocks and we don't want to exceed the | |
| journal flush threshold, sd_log_thresh2. */ | |
| if (current->journal_info == NULL) { | |
| unsigned int jblocks_rqsted, revokes; | |
| jblocks_rqsted = rgd->rd_length + RES_DINODE + | |
| RES_INDIRECT; | |
| isize_blks = gfs2_get_inode_blocks(&ip->i_inode); | |
| if (isize_blks > atomic_read(&sdp->sd_log_thresh2)) | |
| jblocks_rqsted += | |
| atomic_read(&sdp->sd_log_thresh2); | |
| else | |
| jblocks_rqsted += isize_blks; | |
| revokes = jblocks_rqsted; | |
| if (meta) | |
| revokes += hptrs(sdp, hgt); | |
| else if (ip->i_depth) | |
| revokes += sdp->sd_inptrs; | |
| ret = gfs2_trans_begin(sdp, jblocks_rqsted, revokes); | |
| if (ret) | |
| goto out_unlock; | |
| down_write(&ip->i_rw_mutex); | |
| } | |
| /* check if we will exceed the transaction blocks requested */ | |
| tr = current->journal_info; | |
| if (tr->tr_num_buf_new + RES_STATFS + | |
| RES_QUOTA >= atomic_read(&sdp->sd_log_thresh2)) { | |
| /* We set blks_outside_rgrp to ensure the loop will | |
| be repeated for the same rgrp, but with a new | |
| transaction. */ | |
| blks_outside_rgrp++; | |
| /* This next part is tricky. If the buffer was added | |
| to the transaction, we've already set some block | |
| pointers to 0, so we better follow through and free | |
| them, or we will introduce corruption (so break). | |
| This may be impossible, or at least rare, but I | |
| decided to cover the case regardless. | |
| If the buffer was not added to the transaction | |
| (this call), doing so would exceed our transaction | |
| size, so we need to end the transaction and start a | |
| new one (so goto). */ | |
| if (buf_in_tr) | |
| break; | |
| goto out_unlock; | |
| } | |
| gfs2_trans_add_meta(ip->i_gl, bh); | |
| buf_in_tr = true; | |
| *p = 0; | |
| if (bstart + blen == bn) { | |
| blen++; | |
| continue; | |
| } | |
| if (bstart) { | |
| __gfs2_free_blocks(ip, bstart, (u32)blen, meta); | |
| (*btotal) += blen; | |
| gfs2_add_inode_blocks(&ip->i_inode, -blen); | |
| } | |
| bstart = bn; | |
| blen = 1; | |
| } | |
| if (bstart) { | |
| __gfs2_free_blocks(ip, bstart, (u32)blen, meta); | |
| (*btotal) += blen; | |
| gfs2_add_inode_blocks(&ip->i_inode, -blen); | |
| } | |
| out_unlock: | |
| if (!ret && blks_outside_rgrp) { /* If buffer still has non-zero blocks | |
| outside the rgrp we just processed, | |
| do it all over again. */ | |
| if (current->journal_info) { | |
| struct buffer_head *dibh = mp->mp_bh[0]; | |
| /* Every transaction boundary, we rewrite the dinode | |
| to keep its di_blocks current in case of failure. */ | |
| ip->i_inode.i_mtime = ip->i_inode.i_ctime = | |
| current_time(&ip->i_inode); | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| gfs2_dinode_out(ip, dibh->b_data); | |
| up_write(&ip->i_rw_mutex); | |
| gfs2_trans_end(sdp); | |
| } | |
| gfs2_glock_dq_uninit(rd_gh); | |
| cond_resched(); | |
| goto more_rgrps; | |
| } | |
| out: | |
| return ret; | |
| } | |
| /** | |
| * find_nonnull_ptr - find a non-null pointer given a metapath and height | |
| * assumes the metapath is valid (with buffers) out to height h | |
| * @mp: starting metapath | |
| * @h: desired height to search | |
| * | |
| * Returns: true if a non-null pointer was found in the metapath buffer | |
| * false if all remaining pointers are NULL in the buffer | |
| */ | |
| static bool find_nonnull_ptr(struct gfs2_sbd *sdp, struct metapath *mp, | |
| unsigned int h) | |
| { | |
| __be64 *ptr; | |
| unsigned int ptrs = hptrs(sdp, h) - 1; | |
| while (true) { | |
| ptr = metapointer(h, mp); | |
| if (*ptr) { /* if we have a non-null pointer */ | |
| /* Now zero the metapath after the current height. */ | |
| h++; | |
| if (h < GFS2_MAX_META_HEIGHT) | |
| memset(&mp->mp_list[h], 0, | |
| (GFS2_MAX_META_HEIGHT - h) * | |
| sizeof(mp->mp_list[0])); | |
| return true; | |
| } | |
| if (mp->mp_list[h] < ptrs) | |
| mp->mp_list[h]++; | |
| else | |
| return false; /* no more pointers in this buffer */ | |
| } | |
| } | |
| enum dealloc_states { | |
| DEALLOC_MP_FULL = 0, /* Strip a metapath with all buffers read in */ | |
| DEALLOC_MP_LOWER = 1, /* lower the metapath strip height */ | |
| DEALLOC_FILL_MP = 2, /* Fill in the metapath to the given height. */ | |
| DEALLOC_DONE = 3, /* process complete */ | |
| }; | |
| static bool mp_eq_to_hgt(struct metapath *mp, __u16 *nbof, unsigned int h) | |
| { | |
| if (memcmp(mp->mp_list, nbof, h * sizeof(mp->mp_list[0]))) | |
| return false; | |
| return true; | |
| } | |
| /** | |
| * trunc_dealloc - truncate a file down to a desired size | |
| * @ip: inode to truncate | |
| * @newsize: The desired size of the file | |
| * | |
| * This function truncates a file to newsize. It works from the | |
| * bottom up, and from the right to the left. In other words, it strips off | |
| * the highest layer (data) before stripping any of the metadata. Doing it | |
| * this way is best in case the operation is interrupted by power failure, etc. | |
| * The dinode is rewritten in every transaction to guarantee integrity. | |
| */ | |
| static int trunc_dealloc(struct gfs2_inode *ip, u64 newsize) | |
| { | |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); | |
| struct metapath mp; | |
| struct buffer_head *dibh, *bh; | |
| struct gfs2_holder rd_gh; | |
| u64 lblock; | |
| __u16 nbof[GFS2_MAX_META_HEIGHT]; /* new beginning of truncation */ | |
| unsigned int strip_h = ip->i_height - 1; | |
| u32 btotal = 0; | |
| int ret, state; | |
| int mp_h; /* metapath buffers are read in to this height */ | |
| sector_t last_ra = 0; | |
| u64 prev_bnr = 0; | |
| bool preserve1; /* need to preserve the first meta pointer? */ | |
| if (!newsize) | |
| lblock = 0; | |
| else | |
| lblock = (newsize - 1) >> sdp->sd_sb.sb_bsize_shift; | |
| memset(&mp, 0, sizeof(mp)); | |
| find_metapath(sdp, lblock, &mp, ip->i_height); | |
| memcpy(&nbof, &mp.mp_list, sizeof(nbof)); | |
| ret = gfs2_meta_inode_buffer(ip, &dibh); | |
| if (ret) | |
| return ret; | |
| mp.mp_bh[0] = dibh; | |
| ret = lookup_metapath(ip, &mp); | |
| if (ret == ip->i_height) | |
| state = DEALLOC_MP_FULL; /* We have a complete metapath */ | |
| else | |
| state = DEALLOC_FILL_MP; /* deal with partial metapath */ | |
| ret = gfs2_rindex_update(sdp); | |
| if (ret) | |
| goto out_metapath; | |
| ret = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE); | |
| if (ret) | |
| goto out_metapath; | |
| gfs2_holder_mark_uninitialized(&rd_gh); | |
| mp_h = strip_h; | |
| while (state != DEALLOC_DONE) { | |
| switch (state) { | |
| /* Truncate a full metapath at the given strip height. | |
| * Note that strip_h == mp_h in order to be in this state. */ | |
| case DEALLOC_MP_FULL: | |
| if (mp_h > 0) { /* issue read-ahead on metadata */ | |
| __be64 *top; | |
| bh = mp.mp_bh[mp_h - 1]; | |
| if (bh->b_blocknr != last_ra) { | |
| last_ra = bh->b_blocknr; | |
| top = metaptr1(mp_h - 1, &mp); | |
| gfs2_metapath_ra(ip->i_gl, bh, top); | |
| } | |
| } | |
| /* If we're truncating to a non-zero size and the mp is | |
| at the beginning of file for the strip height, we | |
| need to preserve the first metadata pointer. */ | |
| preserve1 = (newsize && mp_eq_to_hgt(&mp, nbof, mp_h)); | |
| bh = mp.mp_bh[mp_h]; | |
| gfs2_assert_withdraw(sdp, bh); | |
| if (gfs2_assert_withdraw(sdp, | |
| prev_bnr != bh->b_blocknr)) { | |
| printk(KERN_EMERG "GFS2: fsid=%s:inode %llu, " | |
| "block:%llu, i_h:%u, s_h:%u, mp_h:%u\n", | |
| sdp->sd_fsname, | |
| (unsigned long long)ip->i_no_addr, | |
| prev_bnr, ip->i_height, strip_h, mp_h); | |
| } | |
| prev_bnr = bh->b_blocknr; | |
| ret = sweep_bh_for_rgrps(ip, &rd_gh, &mp, &btotal, | |
| mp_h, preserve1); | |
| /* If we hit an error or just swept dinode buffer, | |
| just exit. */ | |
| if (ret || !mp_h) { | |
| state = DEALLOC_DONE; | |
| break; | |
| } | |
| state = DEALLOC_MP_LOWER; | |
| break; | |
| /* lower the metapath strip height */ | |
| case DEALLOC_MP_LOWER: | |
| /* We're done with the current buffer, so release it, | |
| unless it's the dinode buffer. Then back up to the | |
| previous pointer. */ | |
| if (mp_h) { | |
| brelse(mp.mp_bh[mp_h]); | |
| mp.mp_bh[mp_h] = NULL; | |
| } | |
| /* If we can't get any lower in height, we've stripped | |
| off all we can. Next step is to back up and start | |
| stripping the previous level of metadata. */ | |
| if (mp_h == 0) { | |
| strip_h--; | |
| memcpy(&mp.mp_list, &nbof, sizeof(nbof)); | |
| mp_h = strip_h; | |
| state = DEALLOC_FILL_MP; | |
| break; | |
| } | |
| mp.mp_list[mp_h] = 0; | |
| mp_h--; /* search one metadata height down */ | |
| if (mp.mp_list[mp_h] >= hptrs(sdp, mp_h) - 1) | |
| break; /* loop around in the same state */ | |
| mp.mp_list[mp_h]++; | |
| /* Here we've found a part of the metapath that is not | |
| * allocated. We need to search at that height for the | |
| * next non-null pointer. */ | |
| if (find_nonnull_ptr(sdp, &mp, mp_h)) { | |
| state = DEALLOC_FILL_MP; | |
| mp_h++; | |
| } | |
| /* No more non-null pointers at this height. Back up | |
| to the previous height and try again. */ | |
| break; /* loop around in the same state */ | |
| /* Fill the metapath with buffers to the given height. */ | |
| case DEALLOC_FILL_MP: | |
| /* Fill the buffers out to the current height. */ | |
| ret = fillup_metapath(ip, &mp, mp_h); | |
| if (ret < 0) | |
| goto out; | |
| /* If buffers found for the entire strip height */ | |
| if ((ret == ip->i_height) && (mp_h == strip_h)) { | |
| state = DEALLOC_MP_FULL; | |
| break; | |
| } | |
| if (ret < ip->i_height) /* We have a partial height */ | |
| mp_h = ret - 1; | |
| /* If we find a non-null block pointer, crawl a bit | |
| higher up in the metapath and try again, otherwise | |
| we need to look lower for a new starting point. */ | |
| if (find_nonnull_ptr(sdp, &mp, mp_h)) | |
| mp_h++; | |
| else | |
| state = DEALLOC_MP_LOWER; | |
| break; | |
| } | |
| } | |
| if (btotal) { | |
| if (current->journal_info == NULL) { | |
| ret = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS + | |
| RES_QUOTA, 0); | |
| if (ret) | |
| goto out; | |
| down_write(&ip->i_rw_mutex); | |
| } | |
| gfs2_statfs_change(sdp, 0, +btotal, 0); | |
| gfs2_quota_change(ip, -(s64)btotal, ip->i_inode.i_uid, | |
| ip->i_inode.i_gid); | |
| ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode); | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| gfs2_dinode_out(ip, dibh->b_data); | |
| up_write(&ip->i_rw_mutex); | |
| gfs2_trans_end(sdp); | |
| } | |
| out: | |
| if (gfs2_holder_initialized(&rd_gh)) | |
| gfs2_glock_dq_uninit(&rd_gh); | |
| if (current->journal_info) { | |
| up_write(&ip->i_rw_mutex); | |
| gfs2_trans_end(sdp); | |
| cond_resched(); | |
| } | |
| gfs2_quota_unhold(ip); | |
| out_metapath: | |
| release_metapath(&mp); | |
| return ret; | |
| } | |
| 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 (!i_size_read(&ip->i_inode)) { | |
| ip->i_height = 0; | |
| ip->i_goal = ip->i_no_addr; | |
| gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); | |
| gfs2_ordered_del_inode(ip); | |
| } | |
| ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode); | |
| ip->i_diskflags &= ~GFS2_DIF_TRUNC_IN_PROG; | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| 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 | |
| * @inode: the inode | |
| * @oldsize: the current inode size | |
| * @newsize: the size to make the file | |
| * | |
| * Called with an exclusive lock on @inode. The @size must | |
| * be equal to or smaller than the current inode size. | |
| * | |
| * Returns: errno | |
| */ | |
| static int do_shrink(struct inode *inode, u64 oldsize, u64 newsize) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| int error; | |
| error = trunc_start(inode, oldsize, newsize); | |
| if (error < 0) | |
| return error; | |
| if (gfs2_is_stuffed(ip)) | |
| return 0; | |
| error = trunc_dealloc(ip, newsize); | |
| if (error == 0) | |
| error = trunc_end(ip); | |
| return error; | |
| } | |
| void gfs2_trim_blocks(struct inode *inode) | |
| { | |
| u64 size = inode->i_size; | |
| int ret; | |
| ret = do_shrink(inode, size, size); | |
| WARN_ON(ret != 0); | |
| } | |
| /** | |
| * do_grow - Touch and update inode size | |
| * @inode: The inode | |
| * @size: The new size | |
| * | |
| * This function updates the timestamps on the inode and | |
| * may also increase the size of the inode. This function | |
| * must not be called with @size any smaller than the current | |
| * inode size. | |
| * | |
| * Although it is not strictly required to unstuff files here, | |
| * earlier versions of GFS2 have a bug in the stuffed file reading | |
| * code which will result in a buffer overrun if the size is larger | |
| * than the max stuffed file size. In order to prevent this from | |
| * occurring, such files are unstuffed, but in other cases we can | |
| * just update the inode size directly. | |
| * | |
| * Returns: 0 on success, or -ve on error | |
| */ | |
| static int do_grow(struct inode *inode, u64 size) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| struct gfs2_sbd *sdp = GFS2_SB(inode); | |
| struct gfs2_alloc_parms ap = { .target = 1, }; | |
| struct buffer_head *dibh; | |
| int error; | |
| int unstuff = 0; | |
| if (gfs2_is_stuffed(ip) && | |
| (size > (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)))) { | |
| error = gfs2_quota_lock_check(ip, &ap); | |
| if (error) | |
| return error; | |
| error = gfs2_inplace_reserve(ip, &ap); | |
| if (error) | |
| goto do_grow_qunlock; | |
| unstuff = 1; | |
| } | |
| error = gfs2_trans_begin(sdp, RES_DINODE + RES_STATFS + RES_RG_BIT + | |
| (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF ? | |
| 0 : RES_QUOTA), 0); | |
| if (error) | |
| goto do_grow_release; | |
| if (unstuff) { | |
| error = gfs2_unstuff_dinode(ip, NULL); | |
| if (error) | |
| goto do_end_trans; | |
| } | |
| error = gfs2_meta_inode_buffer(ip, &dibh); | |
| if (error) | |
| goto do_end_trans; | |
| i_size_write(inode, size); | |
| ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode); | |
| gfs2_trans_add_meta(ip->i_gl, dibh); | |
| gfs2_dinode_out(ip, dibh->b_data); | |
| brelse(dibh); | |
| do_end_trans: | |
| gfs2_trans_end(sdp); | |
| do_grow_release: | |
| if (unstuff) { | |
| gfs2_inplace_release(ip); | |
| do_grow_qunlock: | |
| gfs2_quota_unlock(ip); | |
| } | |
| return error; | |
| } | |
| /** | |
| * gfs2_setattr_size - make a file a given size | |
| * @inode: the inode | |
| * @newsize: the size to make the file | |
| * | |
| * The file size can grow, shrink, or stay the same size. This | |
| * is called holding i_mutex and an exclusive glock on the inode | |
| * in question. | |
| * | |
| * Returns: errno | |
| */ | |
| int gfs2_setattr_size(struct inode *inode, u64 newsize) | |
| { | |
| struct gfs2_inode *ip = GFS2_I(inode); | |
| int ret; | |
| u64 oldsize; | |
| BUG_ON(!S_ISREG(inode->i_mode)); | |
| ret = inode_newsize_ok(inode, newsize); | |
| if (ret) | |
| return ret; | |
| inode_dio_wait(inode); | |
| ret = gfs2_rsqa_alloc(ip); | |
| if (ret) | |
| goto out; | |
| oldsize = inode->i_size; | |
| if (newsize >= oldsize) { | |
| ret = do_grow(inode, newsize); | |
| goto out; | |
| } | |
| ret = do_shrink(inode, oldsize, newsize); | |
| out: | |
| gfs2_rsqa_delete(ip, NULL); | |
| return ret; | |
| } | |
| int gfs2_truncatei_resume(struct gfs2_inode *ip) | |
| { | |
| int error; | |
| error = trunc_dealloc(ip, i_size_read(&ip->i_inode)); | |
| if (!error) | |
| error = trunc_end(ip); | |
| return error; | |
| } | |
| int gfs2_file_dealloc(struct gfs2_inode *ip) | |
| { | |
| return trunc_dealloc(ip, 0); | |
| } | |
| /** | |
| * gfs2_free_journal_extents - Free cached journal bmap info | |
| * @jd: The journal | |
| * | |
| */ | |
| void gfs2_free_journal_extents(struct gfs2_jdesc *jd) | |
| { | |
| struct gfs2_journal_extent *jext; | |
| while(!list_empty(&jd->extent_list)) { | |
| jext = list_entry(jd->extent_list.next, struct gfs2_journal_extent, list); | |
| list_del(&jext->list); | |
| kfree(jext); | |
| } | |
| } | |
| /** | |
| * gfs2_add_jextent - Add or merge a new extent to extent cache | |
| * @jd: The journal descriptor | |
| * @lblock: The logical block at start of new extent | |
| * @dblock: The physical block at start of new extent | |
| * @blocks: Size of extent in fs blocks | |
| * | |
| * Returns: 0 on success or -ENOMEM | |
| */ | |
| static int gfs2_add_jextent(struct gfs2_jdesc *jd, u64 lblock, u64 dblock, u64 blocks) | |
| { | |
| struct gfs2_journal_extent *jext; | |
| if (!list_empty(&jd->extent_list)) { | |
| jext = list_entry(jd->extent_list.prev, struct gfs2_journal_extent, list); | |
| if ((jext->dblock + jext->blocks) == dblock) { | |
| jext->blocks += blocks; | |
| return 0; | |
| } | |
| } | |
| jext = kzalloc(sizeof(struct gfs2_journal_extent), GFP_NOFS); | |
| if (jext == NULL) | |
| return -ENOMEM; | |
| jext->dblock = dblock; | |
| jext->lblock = lblock; | |
| jext->blocks = blocks; | |
| list_add_tail(&jext->list, &jd->extent_list); | |
| jd->nr_extents++; | |
| return 0; | |
| } | |
| /** | |
| * gfs2_map_journal_extents - Cache journal bmap info | |
| * @sdp: The super block | |
| * @jd: The journal to map | |
| * | |
| * Create a reusable "extent" mapping from all logical | |
| * blocks to all physical blocks for the given journal. This will save | |
| * us time when writing journal blocks. Most journals will have only one | |
| * extent that maps all their logical blocks. That's because gfs2.mkfs | |
| * arranges the journal blocks sequentially to maximize performance. | |
| * So the extent would map the first block for the entire file length. | |
| * However, gfs2_jadd can happen while file activity is happening, so | |
| * those journals may not be sequential. Less likely is the case where | |
| * the users created their own journals by mounting the metafs and | |
| * laying it out. But it's still possible. These journals might have | |
| * several extents. | |
| * | |
| * Returns: 0 on success, or error on failure | |
| */ | |
| int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd) | |
| { | |
| u64 lblock = 0; | |
| u64 lblock_stop; | |
| struct gfs2_inode *ip = GFS2_I(jd->jd_inode); | |
| struct buffer_head bh; | |
| unsigned int shift = sdp->sd_sb.sb_bsize_shift; | |
| u64 size; | |
| int rc; | |
| lblock_stop = i_size_read(jd->jd_inode) >> shift; | |
| size = (lblock_stop - lblock) << shift; | |
| jd->nr_extents = 0; | |
| WARN_ON(!list_empty(&jd->extent_list)); | |
| do { | |
| bh.b_state = 0; | |
| bh.b_blocknr = 0; | |
| bh.b_size = size; | |
| rc = gfs2_block_map(jd->jd_inode, lblock, &bh, 0); | |
| if (rc || !buffer_mapped(&bh)) | |
| goto fail; | |
| rc = gfs2_add_jextent(jd, lblock, bh.b_blocknr, bh.b_size >> shift); | |
| if (rc) | |
| goto fail; | |
| size -= bh.b_size; | |
| lblock += (bh.b_size >> ip->i_inode.i_blkbits); | |
| } while(size > 0); | |
| fs_info(sdp, "journal %d mapped with %u extents\n", jd->jd_jid, | |
| jd->nr_extents); | |
| return 0; | |
| fail: | |
| fs_warn(sdp, "error %d mapping journal %u at offset %llu (extent %u)\n", | |
| rc, jd->jd_jid, | |
| (unsigned long long)(i_size_read(jd->jd_inode) - size), | |
| jd->nr_extents); | |
| fs_warn(sdp, "bmap=%d lblock=%llu block=%llu, state=0x%08lx, size=%llu\n", | |
| rc, (unsigned long long)lblock, (unsigned long long)bh.b_blocknr, | |
| bh.b_state, (unsigned long long)bh.b_size); | |
| gfs2_free_journal_extents(jd); | |
| return rc; | |
| } | |
| /** | |
| * 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 | |
| * | |
| * Returns: 1 if an alloc is required, 0 otherwise | |
| */ | |
| int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset, | |
| unsigned int len) | |
| { | |
| struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); | |
| struct buffer_head bh; | |
| unsigned int shift; | |
| u64 lblock, lblock_stop, size; | |
| u64 end_of_file; | |
| if (!len) | |
| return 0; | |
| if (gfs2_is_stuffed(ip)) { | |
| if (offset + len > | |
| sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) | |
| return 1; | |
| return 0; | |
| } | |
| shift = sdp->sd_sb.sb_bsize_shift; | |
| BUG_ON(gfs2_is_dir(ip)); | |
| end_of_file = (i_size_read(&ip->i_inode) + sdp->sd_sb.sb_bsize - 1) >> shift; | |
| lblock = offset >> shift; | |
| lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift; | |
| if (lblock_stop > end_of_file) | |
| return 1; | |
| size = (lblock_stop - lblock) << shift; | |
| do { | |
| bh.b_state = 0; | |
| bh.b_size = size; | |
| gfs2_block_map(&ip->i_inode, lblock, &bh, 0); | |
| if (!buffer_mapped(&bh)) | |
| return 1; | |
| size -= bh.b_size; | |
| lblock += (bh.b_size >> ip->i_inode.i_blkbits); | |
| } while(size > 0); | |
| return 0; | |
| } | |