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Diffstat (limited to 'fs/gfs2/rgrp.c')
| -rw-r--r-- | fs/gfs2/rgrp.c | 2770 |
1 files changed, 2770 insertions, 0 deletions
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c new file mode 100644 index 000000000..dcaaa32ef --- /dev/null +++ b/fs/gfs2/rgrp.c @@ -0,0 +1,2770 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/completion.h> +#include <linux/buffer_head.h> +#include <linux/fs.h> +#include <linux/gfs2_ondisk.h> +#include <linux/prefetch.h> +#include <linux/blkdev.h> +#include <linux/rbtree.h> +#include <linux/random.h> + +#include "gfs2.h" +#include "incore.h" +#include "glock.h" +#include "glops.h" +#include "lops.h" +#include "meta_io.h" +#include "quota.h" +#include "rgrp.h" +#include "super.h" +#include "trans.h" +#include "util.h" +#include "log.h" +#include "inode.h" +#include "trace_gfs2.h" +#include "dir.h" + +#define BFITNOENT ((u32)~0) +#define NO_BLOCK ((u64)~0) + +struct gfs2_rbm { + struct gfs2_rgrpd *rgd; + u32 offset; /* The offset is bitmap relative */ + int bii; /* Bitmap index */ +}; + +static inline struct gfs2_bitmap *rbm_bi(const struct gfs2_rbm *rbm) +{ + return rbm->rgd->rd_bits + rbm->bii; +} + +static inline u64 gfs2_rbm_to_block(const struct gfs2_rbm *rbm) +{ + BUG_ON(rbm->offset >= rbm->rgd->rd_data); + return rbm->rgd->rd_data0 + (rbm_bi(rbm)->bi_start * GFS2_NBBY) + + rbm->offset; +} + +/* + * These routines are used by the resource group routines (rgrp.c) + * to keep track of block allocation. Each block is represented by two + * bits. So, each byte represents GFS2_NBBY (i.e. 4) blocks. + * + * 0 = Free + * 1 = Used (not metadata) + * 2 = Unlinked (still in use) inode + * 3 = Used (metadata) + */ + +struct gfs2_extent { + struct gfs2_rbm rbm; + u32 len; +}; + +static const char valid_change[16] = { + /* current */ + /* n */ 0, 1, 1, 1, + /* e */ 1, 0, 0, 0, + /* w */ 0, 0, 0, 1, + 1, 0, 0, 0 +}; + +static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext, + struct gfs2_blkreserv *rs, bool nowrap); + + +/** + * gfs2_setbit - Set a bit in the bitmaps + * @rbm: The position of the bit to set + * @do_clone: Also set the clone bitmap, if it exists + * @new_state: the new state of the block + * + */ + +static inline void gfs2_setbit(const struct gfs2_rbm *rbm, bool do_clone, + unsigned char new_state) +{ + unsigned char *byte1, *byte2, *end, cur_state; + struct gfs2_bitmap *bi = rbm_bi(rbm); + unsigned int buflen = bi->bi_bytes; + const unsigned int bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE; + + byte1 = bi->bi_bh->b_data + bi->bi_offset + (rbm->offset / GFS2_NBBY); + end = bi->bi_bh->b_data + bi->bi_offset + buflen; + + BUG_ON(byte1 >= end); + + cur_state = (*byte1 >> bit) & GFS2_BIT_MASK; + + if (unlikely(!valid_change[new_state * 4 + cur_state])) { + struct gfs2_sbd *sdp = rbm->rgd->rd_sbd; + + fs_warn(sdp, "buf_blk = 0x%x old_state=%d, new_state=%d\n", + rbm->offset, cur_state, new_state); + fs_warn(sdp, "rgrp=0x%llx bi_start=0x%x biblk: 0x%llx\n", + (unsigned long long)rbm->rgd->rd_addr, bi->bi_start, + (unsigned long long)bi->bi_bh->b_blocknr); + fs_warn(sdp, "bi_offset=0x%x bi_bytes=0x%x block=0x%llx\n", + bi->bi_offset, bi->bi_bytes, + (unsigned long long)gfs2_rbm_to_block(rbm)); + dump_stack(); + gfs2_consist_rgrpd(rbm->rgd); + return; + } + *byte1 ^= (cur_state ^ new_state) << bit; + + if (do_clone && bi->bi_clone) { + byte2 = bi->bi_clone + bi->bi_offset + (rbm->offset / GFS2_NBBY); + cur_state = (*byte2 >> bit) & GFS2_BIT_MASK; + *byte2 ^= (cur_state ^ new_state) << bit; + } +} + +/** + * gfs2_testbit - test a bit in the bitmaps + * @rbm: The bit to test + * @use_clone: If true, test the clone bitmap, not the official bitmap. + * + * Some callers like gfs2_unaligned_extlen need to test the clone bitmaps, + * not the "real" bitmaps, to avoid allocating recently freed blocks. + * + * Returns: The two bit block state of the requested bit + */ + +static inline u8 gfs2_testbit(const struct gfs2_rbm *rbm, bool use_clone) +{ + struct gfs2_bitmap *bi = rbm_bi(rbm); + const u8 *buffer; + const u8 *byte; + unsigned int bit; + + if (use_clone && bi->bi_clone) + buffer = bi->bi_clone; + else + buffer = bi->bi_bh->b_data; + buffer += bi->bi_offset; + byte = buffer + (rbm->offset / GFS2_NBBY); + bit = (rbm->offset % GFS2_NBBY) * GFS2_BIT_SIZE; + + return (*byte >> bit) & GFS2_BIT_MASK; +} + +/** + * gfs2_bit_search + * @ptr: Pointer to bitmap data + * @mask: Mask to use (normally 0x55555.... but adjusted for search start) + * @state: The state we are searching for + * + * We xor the bitmap data with a patter which is the bitwise opposite + * of what we are looking for, this gives rise to a pattern of ones + * wherever there is a match. Since we have two bits per entry, we + * take this pattern, shift it down by one place and then and it with + * the original. All the even bit positions (0,2,4, etc) then represent + * successful matches, so we mask with 0x55555..... to remove the unwanted + * odd bit positions. + * + * This allows searching of a whole u64 at once (32 blocks) with a + * single test (on 64 bit arches). + */ + +static inline u64 gfs2_bit_search(const __le64 *ptr, u64 mask, u8 state) +{ + u64 tmp; + static const u64 search[] = { + [0] = 0xffffffffffffffffULL, + [1] = 0xaaaaaaaaaaaaaaaaULL, + [2] = 0x5555555555555555ULL, + [3] = 0x0000000000000000ULL, + }; + tmp = le64_to_cpu(*ptr) ^ search[state]; + tmp &= (tmp >> 1); + tmp &= mask; + return tmp; +} + +/** + * rs_cmp - multi-block reservation range compare + * @start: start of the new reservation + * @len: number of blocks in the new reservation + * @rs: existing reservation to compare against + * + * returns: 1 if the block range is beyond the reach of the reservation + * -1 if the block range is before the start of the reservation + * 0 if the block range overlaps with the reservation + */ +static inline int rs_cmp(u64 start, u32 len, struct gfs2_blkreserv *rs) +{ + if (start >= rs->rs_start + rs->rs_requested) + return 1; + if (rs->rs_start >= start + len) + return -1; + return 0; +} + +/** + * gfs2_bitfit - Search an rgrp's bitmap buffer to find a bit-pair representing + * a block in a given allocation state. + * @buf: the buffer that holds the bitmaps + * @len: the length (in bytes) of the buffer + * @goal: start search at this block's bit-pair (within @buffer) + * @state: GFS2_BLKST_XXX the state of the block we're looking for. + * + * Scope of @goal and returned block number is only within this bitmap buffer, + * not entire rgrp or filesystem. @buffer will be offset from the actual + * beginning of a bitmap block buffer, skipping any header structures, but + * headers are always a multiple of 64 bits long so that the buffer is + * always aligned to a 64 bit boundary. + * + * The size of the buffer is in bytes, but is it assumed that it is + * always ok to read a complete multiple of 64 bits at the end + * of the block in case the end is no aligned to a natural boundary. + * + * Return: the block number (bitmap buffer scope) that was found + */ + +static u32 gfs2_bitfit(const u8 *buf, const unsigned int len, + u32 goal, u8 state) +{ + u32 spoint = (goal << 1) & ((8*sizeof(u64)) - 1); + const __le64 *ptr = ((__le64 *)buf) + (goal >> 5); + const __le64 *end = (__le64 *)(buf + ALIGN(len, sizeof(u64))); + u64 tmp; + u64 mask = 0x5555555555555555ULL; + u32 bit; + + /* Mask off bits we don't care about at the start of the search */ + mask <<= spoint; + tmp = gfs2_bit_search(ptr, mask, state); + ptr++; + while(tmp == 0 && ptr < end) { + tmp = gfs2_bit_search(ptr, 0x5555555555555555ULL, state); + ptr++; + } + /* Mask off any bits which are more than len bytes from the start */ + if (ptr == end && (len & (sizeof(u64) - 1))) + tmp &= (((u64)~0) >> (64 - 8*(len & (sizeof(u64) - 1)))); + /* Didn't find anything, so return */ + if (tmp == 0) + return BFITNOENT; + ptr--; + bit = __ffs64(tmp); + bit /= 2; /* two bits per entry in the bitmap */ + return (((const unsigned char *)ptr - buf) * GFS2_NBBY) + bit; +} + +/** + * gfs2_rbm_from_block - Set the rbm based upon rgd and block number + * @rbm: The rbm with rgd already set correctly + * @block: The block number (filesystem relative) + * + * This sets the bi and offset members of an rbm based on a + * resource group and a filesystem relative block number. The + * resource group must be set in the rbm on entry, the bi and + * offset members will be set by this function. + * + * Returns: 0 on success, or an error code + */ + +static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block) +{ + if (!rgrp_contains_block(rbm->rgd, block)) + return -E2BIG; + rbm->bii = 0; + rbm->offset = block - rbm->rgd->rd_data0; + /* Check if the block is within the first block */ + if (rbm->offset < rbm_bi(rbm)->bi_blocks) + return 0; + + /* Adjust for the size diff between gfs2_meta_header and gfs2_rgrp */ + rbm->offset += (sizeof(struct gfs2_rgrp) - + sizeof(struct gfs2_meta_header)) * GFS2_NBBY; + rbm->bii = rbm->offset / rbm->rgd->rd_sbd->sd_blocks_per_bitmap; + rbm->offset -= rbm->bii * rbm->rgd->rd_sbd->sd_blocks_per_bitmap; + return 0; +} + +/** + * gfs2_rbm_add - add a number of blocks to an rbm + * @rbm: The rbm with rgd already set correctly + * @blocks: The number of blocks to add to rpm + * + * This function takes an existing rbm structure and adds a number of blocks to + * it. + * + * Returns: True if the new rbm would point past the end of the rgrp. + */ + +static bool gfs2_rbm_add(struct gfs2_rbm *rbm, u32 blocks) +{ + struct gfs2_rgrpd *rgd = rbm->rgd; + struct gfs2_bitmap *bi = rgd->rd_bits + rbm->bii; + + if (rbm->offset + blocks < bi->bi_blocks) { + rbm->offset += blocks; + return false; + } + blocks -= bi->bi_blocks - rbm->offset; + + for(;;) { + bi++; + if (bi == rgd->rd_bits + rgd->rd_length) + return true; + if (blocks < bi->bi_blocks) { + rbm->offset = blocks; + rbm->bii = bi - rgd->rd_bits; + return false; + } + blocks -= bi->bi_blocks; + } +} + +/** + * gfs2_unaligned_extlen - Look for free blocks which are not byte aligned + * @rbm: Position to search (value/result) + * @n_unaligned: Number of unaligned blocks to check + * @len: Decremented for each block found (terminate on zero) + * + * Returns: true if a non-free block is encountered or the end of the resource + * group is reached. + */ + +static bool gfs2_unaligned_extlen(struct gfs2_rbm *rbm, u32 n_unaligned, u32 *len) +{ + u32 n; + u8 res; + + for (n = 0; n < n_unaligned; n++) { + res = gfs2_testbit(rbm, true); + if (res != GFS2_BLKST_FREE) + return true; + (*len)--; + if (*len == 0) + return true; + if (gfs2_rbm_add(rbm, 1)) + return true; + } + + return false; +} + +/** + * gfs2_free_extlen - Return extent length of free blocks + * @rrbm: Starting position + * @len: Max length to check + * + * Starting at the block specified by the rbm, see how many free blocks + * there are, not reading more than len blocks ahead. This can be done + * using memchr_inv when the blocks are byte aligned, but has to be done + * on a block by block basis in case of unaligned blocks. Also this + * function can cope with bitmap boundaries (although it must stop on + * a resource group boundary) + * + * Returns: Number of free blocks in the extent + */ + +static u32 gfs2_free_extlen(const struct gfs2_rbm *rrbm, u32 len) +{ + struct gfs2_rbm rbm = *rrbm; + u32 n_unaligned = rbm.offset & 3; + u32 size = len; + u32 bytes; + u32 chunk_size; + u8 *ptr, *start, *end; + u64 block; + struct gfs2_bitmap *bi; + + if (n_unaligned && + gfs2_unaligned_extlen(&rbm, 4 - n_unaligned, &len)) + goto out; + + n_unaligned = len & 3; + /* Start is now byte aligned */ + while (len > 3) { + bi = rbm_bi(&rbm); + start = bi->bi_bh->b_data; + if (bi->bi_clone) + start = bi->bi_clone; + start += bi->bi_offset; + end = start + bi->bi_bytes; + BUG_ON(rbm.offset & 3); + start += (rbm.offset / GFS2_NBBY); + bytes = min_t(u32, len / GFS2_NBBY, (end - start)); + ptr = memchr_inv(start, 0, bytes); + chunk_size = ((ptr == NULL) ? bytes : (ptr - start)); + chunk_size *= GFS2_NBBY; + BUG_ON(len < chunk_size); + len -= chunk_size; + block = gfs2_rbm_to_block(&rbm); + if (gfs2_rbm_from_block(&rbm, block + chunk_size)) { + n_unaligned = 0; + break; + } + if (ptr) { + n_unaligned = 3; + break; + } + n_unaligned = len & 3; + } + + /* Deal with any bits left over at the end */ + if (n_unaligned) + gfs2_unaligned_extlen(&rbm, n_unaligned, &len); +out: + return size - len; +} + +/** + * gfs2_bitcount - count the number of bits in a certain state + * @rgd: the resource group descriptor + * @buffer: the buffer that holds the bitmaps + * @buflen: the length (in bytes) of the buffer + * @state: the state of the block we're looking for + * + * Returns: The number of bits + */ + +static u32 gfs2_bitcount(struct gfs2_rgrpd *rgd, const u8 *buffer, + unsigned int buflen, u8 state) +{ + const u8 *byte = buffer; + const u8 *end = buffer + buflen; + const u8 state1 = state << 2; + const u8 state2 = state << 4; + const u8 state3 = state << 6; + u32 count = 0; + + for (; byte < end; byte++) { + if (((*byte) & 0x03) == state) + count++; + if (((*byte) & 0x0C) == state1) + count++; + if (((*byte) & 0x30) == state2) + count++; + if (((*byte) & 0xC0) == state3) + count++; + } + + return count; +} + +/** + * gfs2_rgrp_verify - Verify that a resource group is consistent + * @rgd: the rgrp + * + */ + +void gfs2_rgrp_verify(struct gfs2_rgrpd *rgd) +{ + struct gfs2_sbd *sdp = rgd->rd_sbd; + struct gfs2_bitmap *bi = NULL; + u32 length = rgd->rd_length; + u32 count[4], tmp; + int buf, x; + + memset(count, 0, 4 * sizeof(u32)); + + /* Count # blocks in each of 4 possible allocation states */ + for (buf = 0; buf < length; buf++) { + bi = rgd->rd_bits + buf; + for (x = 0; x < 4; x++) + count[x] += gfs2_bitcount(rgd, + bi->bi_bh->b_data + + bi->bi_offset, + bi->bi_bytes, x); + } + + if (count[0] != rgd->rd_free) { + gfs2_lm(sdp, "free data mismatch: %u != %u\n", + count[0], rgd->rd_free); + gfs2_consist_rgrpd(rgd); + return; + } + + tmp = rgd->rd_data - rgd->rd_free - rgd->rd_dinodes; + if (count[1] != tmp) { + gfs2_lm(sdp, "used data mismatch: %u != %u\n", + count[1], tmp); + gfs2_consist_rgrpd(rgd); + return; + } + + if (count[2] + count[3] != rgd->rd_dinodes) { + gfs2_lm(sdp, "used metadata mismatch: %u != %u\n", + count[2] + count[3], rgd->rd_dinodes); + gfs2_consist_rgrpd(rgd); + return; + } +} + +/** + * gfs2_blk2rgrpd - Find resource group for a given data/meta block number + * @sdp: The GFS2 superblock + * @blk: The data block number + * @exact: True if this needs to be an exact match + * + * The @exact argument should be set to true by most callers. The exception + * is when we need to match blocks which are not represented by the rgrp + * bitmap, but which are part of the rgrp (i.e. padding blocks) which are + * there for alignment purposes. Another way of looking at it is that @exact + * matches only valid data/metadata blocks, but with @exact false, it will + * match any block within the extent of the rgrp. + * + * Returns: The resource group, or NULL if not found + */ + +struct gfs2_rgrpd *gfs2_blk2rgrpd(struct gfs2_sbd *sdp, u64 blk, bool exact) +{ + struct rb_node *n, *next; + struct gfs2_rgrpd *cur; + + spin_lock(&sdp->sd_rindex_spin); + n = sdp->sd_rindex_tree.rb_node; + while (n) { + cur = rb_entry(n, struct gfs2_rgrpd, rd_node); + next = NULL; + if (blk < cur->rd_addr) + next = n->rb_left; + else if (blk >= cur->rd_data0 + cur->rd_data) + next = n->rb_right; + if (next == NULL) { + spin_unlock(&sdp->sd_rindex_spin); + if (exact) { + if (blk < cur->rd_addr) + return NULL; + if (blk >= cur->rd_data0 + cur->rd_data) + return NULL; + } + return cur; + } + n = next; + } + spin_unlock(&sdp->sd_rindex_spin); + + return NULL; +} + +/** + * gfs2_rgrpd_get_first - get the first Resource Group in the filesystem + * @sdp: The GFS2 superblock + * + * Returns: The first rgrp in the filesystem + */ + +struct gfs2_rgrpd *gfs2_rgrpd_get_first(struct gfs2_sbd *sdp) +{ + const struct rb_node *n; + struct gfs2_rgrpd *rgd; + + spin_lock(&sdp->sd_rindex_spin); + n = rb_first(&sdp->sd_rindex_tree); + rgd = rb_entry(n, struct gfs2_rgrpd, rd_node); + spin_unlock(&sdp->sd_rindex_spin); + + return rgd; +} + +/** + * gfs2_rgrpd_get_next - get the next RG + * @rgd: the resource group descriptor + * + * Returns: The next rgrp + */ + +struct gfs2_rgrpd *gfs2_rgrpd_get_next(struct gfs2_rgrpd *rgd) +{ + struct gfs2_sbd *sdp = rgd->rd_sbd; + const struct rb_node *n; + + spin_lock(&sdp->sd_rindex_spin); + n = rb_next(&rgd->rd_node); + if (n == NULL) + n = rb_first(&sdp->sd_rindex_tree); + + if (unlikely(&rgd->rd_node == n)) { + spin_unlock(&sdp->sd_rindex_spin); + return NULL; + } + rgd = rb_entry(n, struct gfs2_rgrpd, rd_node); + spin_unlock(&sdp->sd_rindex_spin); + return rgd; +} + +void check_and_update_goal(struct gfs2_inode *ip) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + if (!ip->i_goal || gfs2_blk2rgrpd(sdp, ip->i_goal, 1) == NULL) + ip->i_goal = ip->i_no_addr; +} + +void gfs2_free_clones(struct gfs2_rgrpd *rgd) +{ + int x; + + for (x = 0; x < rgd->rd_length; x++) { + struct gfs2_bitmap *bi = rgd->rd_bits + x; + kfree(bi->bi_clone); + bi->bi_clone = NULL; + } +} + +static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs, + const char *fs_id_buf) +{ + struct gfs2_inode *ip = container_of(rs, struct gfs2_inode, i_res); + + gfs2_print_dbg(seq, "%s B: n:%llu s:%llu f:%u\n", + fs_id_buf, + (unsigned long long)ip->i_no_addr, + (unsigned long long)rs->rs_start, + rs->rs_requested); +} + +/** + * __rs_deltree - remove a multi-block reservation from the rgd tree + * @rs: The reservation to remove + * + */ +static void __rs_deltree(struct gfs2_blkreserv *rs) +{ + struct gfs2_rgrpd *rgd; + + if (!gfs2_rs_active(rs)) + return; + + rgd = rs->rs_rgd; + trace_gfs2_rs(rs, TRACE_RS_TREEDEL); + rb_erase(&rs->rs_node, &rgd->rd_rstree); + RB_CLEAR_NODE(&rs->rs_node); + + if (rs->rs_requested) { + /* return requested blocks to the rgrp */ + BUG_ON(rs->rs_rgd->rd_requested < rs->rs_requested); + rs->rs_rgd->rd_requested -= rs->rs_requested; + + /* The rgrp extent failure point is likely not to increase; + it will only do so if the freed blocks are somehow + contiguous with a span of free blocks that follows. Still, + it will force the number to be recalculated later. */ + rgd->rd_extfail_pt += rs->rs_requested; + rs->rs_requested = 0; + } +} + +/** + * gfs2_rs_deltree - remove a multi-block reservation from the rgd tree + * @rs: The reservation to remove + * + */ +void gfs2_rs_deltree(struct gfs2_blkreserv *rs) +{ + struct gfs2_rgrpd *rgd; + + rgd = rs->rs_rgd; + if (rgd) { + spin_lock(&rgd->rd_rsspin); + __rs_deltree(rs); + BUG_ON(rs->rs_requested); + spin_unlock(&rgd->rd_rsspin); + } +} + +/** + * gfs2_rs_delete - delete a multi-block reservation + * @ip: The inode for this reservation + * + */ +void gfs2_rs_delete(struct gfs2_inode *ip) +{ + struct inode *inode = &ip->i_inode; + + down_write(&ip->i_rw_mutex); + if (atomic_read(&inode->i_writecount) <= 1) + gfs2_rs_deltree(&ip->i_res); + up_write(&ip->i_rw_mutex); +} + +/** + * return_all_reservations - return all reserved blocks back to the rgrp. + * @rgd: the rgrp that needs its space back + * + * We previously reserved a bunch of blocks for allocation. Now we need to + * give them back. This leave the reservation structures in tact, but removes + * all of their corresponding "no-fly zones". + */ +static void return_all_reservations(struct gfs2_rgrpd *rgd) +{ + struct rb_node *n; + struct gfs2_blkreserv *rs; + + spin_lock(&rgd->rd_rsspin); + while ((n = rb_first(&rgd->rd_rstree))) { + rs = rb_entry(n, struct gfs2_blkreserv, rs_node); + __rs_deltree(rs); + } + spin_unlock(&rgd->rd_rsspin); +} + +void gfs2_clear_rgrpd(struct gfs2_sbd *sdp) +{ + struct rb_node *n; + struct gfs2_rgrpd *rgd; + struct gfs2_glock *gl; + + while ((n = rb_first(&sdp->sd_rindex_tree))) { + rgd = rb_entry(n, struct gfs2_rgrpd, rd_node); + gl = rgd->rd_gl; + + rb_erase(n, &sdp->sd_rindex_tree); + + if (gl) { + if (gl->gl_state != LM_ST_UNLOCKED) { + gfs2_glock_cb(gl, LM_ST_UNLOCKED); + flush_delayed_work(&gl->gl_work); + } + gfs2_rgrp_brelse(rgd); + glock_clear_object(gl, rgd); + gfs2_glock_put(gl); + } + + gfs2_free_clones(rgd); + return_all_reservations(rgd); + kfree(rgd->rd_bits); + rgd->rd_bits = NULL; + kmem_cache_free(gfs2_rgrpd_cachep, rgd); + } +} + +/** + * compute_bitstructs - Compute the bitmap sizes + * @rgd: The resource group descriptor + * + * Calculates bitmap descriptors, one for each block that contains bitmap data + * + * Returns: errno + */ + +static int compute_bitstructs(struct gfs2_rgrpd *rgd) +{ + struct gfs2_sbd *sdp = rgd->rd_sbd; + struct gfs2_bitmap *bi; + u32 length = rgd->rd_length; /* # blocks in hdr & bitmap */ + u32 bytes_left, bytes; + int x; + + if (!length) + return -EINVAL; + + rgd->rd_bits = kcalloc(length, sizeof(struct gfs2_bitmap), GFP_NOFS); + if (!rgd->rd_bits) + return -ENOMEM; + + bytes_left = rgd->rd_bitbytes; + + for (x = 0; x < length; x++) { + bi = rgd->rd_bits + x; + + bi->bi_flags = 0; + /* small rgrp; bitmap stored completely in header block */ + if (length == 1) { + bytes = bytes_left; + bi->bi_offset = sizeof(struct gfs2_rgrp); + bi->bi_start = 0; + bi->bi_bytes = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; + /* header block */ + } else if (x == 0) { + bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp); + bi->bi_offset = sizeof(struct gfs2_rgrp); + bi->bi_start = 0; + bi->bi_bytes = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; + /* last block */ + } else if (x + 1 == length) { + bytes = bytes_left; + bi->bi_offset = sizeof(struct gfs2_meta_header); + bi->bi_start = rgd->rd_bitbytes - bytes_left; + bi->bi_bytes = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; + /* other blocks */ + } else { + bytes = sdp->sd_sb.sb_bsize - + sizeof(struct gfs2_meta_header); + bi->bi_offset = sizeof(struct gfs2_meta_header); + bi->bi_start = rgd->rd_bitbytes - bytes_left; + bi->bi_bytes = bytes; + bi->bi_blocks = bytes * GFS2_NBBY; + } + + bytes_left -= bytes; + } + + if (bytes_left) { + gfs2_consist_rgrpd(rgd); + return -EIO; + } + bi = rgd->rd_bits + (length - 1); + if ((bi->bi_start + bi->bi_bytes) * GFS2_NBBY != rgd->rd_data) { + gfs2_lm(sdp, + "ri_addr = %llu\n" + "ri_length = %u\n" + "ri_data0 = %llu\n" + "ri_data = %u\n" + "ri_bitbytes = %u\n" + "start=%u len=%u offset=%u\n", + (unsigned long long)rgd->rd_addr, + rgd->rd_length, + (unsigned long long)rgd->rd_data0, + rgd->rd_data, + rgd->rd_bitbytes, + bi->bi_start, bi->bi_bytes, bi->bi_offset); + gfs2_consist_rgrpd(rgd); + return -EIO; + } + + return 0; +} + +/** + * gfs2_ri_total - Total up the file system space, according to the rindex. + * @sdp: the filesystem + * + */ +u64 gfs2_ri_total(struct gfs2_sbd *sdp) +{ + u64 total_data = 0; + struct inode *inode = sdp->sd_rindex; + struct gfs2_inode *ip = GFS2_I(inode); + char buf[sizeof(struct gfs2_rindex)]; + int error, rgrps; + + for (rgrps = 0;; rgrps++) { + loff_t pos = rgrps * sizeof(struct gfs2_rindex); + + if (pos + sizeof(struct gfs2_rindex) > i_size_read(inode)) + break; + error = gfs2_internal_read(ip, buf, &pos, + sizeof(struct gfs2_rindex)); + if (error != sizeof(struct gfs2_rindex)) + break; + total_data += be32_to_cpu(((struct gfs2_rindex *)buf)->ri_data); + } + return total_data; +} + +static int rgd_insert(struct gfs2_rgrpd *rgd) +{ + struct gfs2_sbd *sdp = rgd->rd_sbd; + struct rb_node **newn = &sdp->sd_rindex_tree.rb_node, *parent = NULL; + + /* Figure out where to put new node */ + while (*newn) { + struct gfs2_rgrpd *cur = rb_entry(*newn, struct gfs2_rgrpd, + rd_node); + + parent = *newn; + if (rgd->rd_addr < cur->rd_addr) + newn = &((*newn)->rb_left); + else if (rgd->rd_addr > cur->rd_addr) + newn = &((*newn)->rb_right); + else + return -EEXIST; + } + + rb_link_node(&rgd->rd_node, parent, newn); + rb_insert_color(&rgd->rd_node, &sdp->sd_rindex_tree); + sdp->sd_rgrps++; + return 0; +} + +/** + * read_rindex_entry - Pull in a new resource index entry from the disk + * @ip: Pointer to the rindex inode + * + * Returns: 0 on success, > 0 on EOF, error code otherwise + */ + +static int read_rindex_entry(struct gfs2_inode *ip) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex); + struct gfs2_rindex buf; + int error; + struct gfs2_rgrpd *rgd; + + if (pos >= i_size_read(&ip->i_inode)) + return 1; + + error = gfs2_internal_read(ip, (char *)&buf, &pos, + sizeof(struct gfs2_rindex)); + + if (error != sizeof(struct gfs2_rindex)) + return (error == 0) ? 1 : error; + + rgd = kmem_cache_zalloc(gfs2_rgrpd_cachep, GFP_NOFS); + error = -ENOMEM; + if (!rgd) + return error; + + rgd->rd_sbd = sdp; + rgd->rd_addr = be64_to_cpu(buf.ri_addr); + rgd->rd_length = be32_to_cpu(buf.ri_length); + rgd->rd_data0 = be64_to_cpu(buf.ri_data0); + rgd->rd_data = be32_to_cpu(buf.ri_data); + rgd->rd_bitbytes = be32_to_cpu(buf.ri_bitbytes); + spin_lock_init(&rgd->rd_rsspin); + mutex_init(&rgd->rd_mutex); + + error = gfs2_glock_get(sdp, rgd->rd_addr, + &gfs2_rgrp_glops, CREATE, &rgd->rd_gl); + if (error) + goto fail; + + error = compute_bitstructs(rgd); + if (error) + goto fail_glock; + + rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lksb.sb_lvbptr; + rgd->rd_flags &= ~GFS2_RDF_PREFERRED; + if (rgd->rd_data > sdp->sd_max_rg_data) + sdp->sd_max_rg_data = rgd->rd_data; + spin_lock(&sdp->sd_rindex_spin); + error = rgd_insert(rgd); + spin_unlock(&sdp->sd_rindex_spin); + if (!error) { + glock_set_object(rgd->rd_gl, rgd); + return 0; + } + + error = 0; /* someone else read in the rgrp; free it and ignore it */ +fail_glock: + gfs2_glock_put(rgd->rd_gl); + +fail: + kfree(rgd->rd_bits); + rgd->rd_bits = NULL; + kmem_cache_free(gfs2_rgrpd_cachep, rgd); + return error; +} + +/** + * set_rgrp_preferences - Run all the rgrps, selecting some we prefer to use + * @sdp: the GFS2 superblock + * + * The purpose of this function is to select a subset of the resource groups + * and mark them as PREFERRED. We do it in such a way that each node prefers + * to use a unique set of rgrps to minimize glock contention. + */ +static void set_rgrp_preferences(struct gfs2_sbd *sdp) +{ + struct gfs2_rgrpd *rgd, *first; + int i; + + /* Skip an initial number of rgrps, based on this node's journal ID. + That should start each node out on its own set. */ + rgd = gfs2_rgrpd_get_first(sdp); + for (i = 0; i < sdp->sd_lockstruct.ls_jid; i++) + rgd = gfs2_rgrpd_get_next(rgd); + first = rgd; + + do { + rgd->rd_flags |= GFS2_RDF_PREFERRED; + for (i = 0; i < sdp->sd_journals; i++) { + rgd = gfs2_rgrpd_get_next(rgd); + if (!rgd || rgd == first) + break; + } + } while (rgd && rgd != first); +} + +/** + * gfs2_ri_update - Pull in a new resource index from the disk + * @ip: pointer to the rindex inode + * + * Returns: 0 on successful update, error code otherwise + */ + +static int gfs2_ri_update(struct gfs2_inode *ip) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + int error; + + do { + error = read_rindex_entry(ip); + } while (error == 0); + + if (error < 0) + return error; + + if (RB_EMPTY_ROOT(&sdp->sd_rindex_tree)) { + fs_err(sdp, "no resource groups found in the file system.\n"); + return -ENOENT; + } + set_rgrp_preferences(sdp); + + sdp->sd_rindex_uptodate = 1; + return 0; +} + +/** + * gfs2_rindex_update - Update the rindex if required + * @sdp: The GFS2 superblock + * + * We grab a lock on the rindex inode to make sure that it doesn't + * change whilst we are performing an operation. We keep this lock + * for quite long periods of time compared to other locks. This + * doesn't matter, since it is shared and it is very, very rarely + * accessed in the exclusive mode (i.e. only when expanding the filesystem). + * + * This makes sure that we're using the latest copy of the resource index + * special file, which might have been updated if someone expanded the + * filesystem (via gfs2_grow utility), which adds new resource groups. + * + * Returns: 0 on succeess, error code otherwise + */ + +int gfs2_rindex_update(struct gfs2_sbd *sdp) +{ + struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex); + struct gfs2_glock *gl = ip->i_gl; + struct gfs2_holder ri_gh; + int error = 0; + int unlock_required = 0; + + /* Read new copy from disk if we don't have the latest */ + if (!sdp->sd_rindex_uptodate) { + if (!gfs2_glock_is_locked_by_me(gl)) { + error = gfs2_glock_nq_init(gl, LM_ST_SHARED, 0, &ri_gh); + if (error) + return error; + unlock_required = 1; + } + if (!sdp->sd_rindex_uptodate) + error = gfs2_ri_update(ip); + if (unlock_required) + gfs2_glock_dq_uninit(&ri_gh); + } + + return error; +} + +static void gfs2_rgrp_in(struct gfs2_rgrpd *rgd, const void *buf) +{ + const struct gfs2_rgrp *str = buf; + u32 rg_flags; + + rg_flags = be32_to_cpu(str->rg_flags); + rg_flags &= ~GFS2_RDF_MASK; + rgd->rd_flags &= GFS2_RDF_MASK; + rgd->rd_flags |= rg_flags; + rgd->rd_free = be32_to_cpu(str->rg_free); + rgd->rd_dinodes = be32_to_cpu(str->rg_dinodes); + rgd->rd_igeneration = be64_to_cpu(str->rg_igeneration); + /* rd_data0, rd_data and rd_bitbytes already set from rindex */ +} + +static void gfs2_rgrp_ondisk2lvb(struct gfs2_rgrp_lvb *rgl, const void *buf) +{ + const struct gfs2_rgrp *str = buf; + + rgl->rl_magic = cpu_to_be32(GFS2_MAGIC); + rgl->rl_flags = str->rg_flags; + rgl->rl_free = str->rg_free; + rgl->rl_dinodes = str->rg_dinodes; + rgl->rl_igeneration = str->rg_igeneration; + rgl->__pad = 0UL; +} + +static void gfs2_rgrp_out(struct gfs2_rgrpd *rgd, void *buf) +{ + struct gfs2_rgrpd *next = gfs2_rgrpd_get_next(rgd); + struct gfs2_rgrp *str = buf; + u32 crc; + + str->rg_flags = cpu_to_be32(rgd->rd_flags & ~GFS2_RDF_MASK); + str->rg_free = cpu_to_be32(rgd->rd_free); + str->rg_dinodes = cpu_to_be32(rgd->rd_dinodes); + if (next == NULL) + str->rg_skip = 0; + else if (next->rd_addr > rgd->rd_addr) + str->rg_skip = cpu_to_be32(next->rd_addr - rgd->rd_addr); + str->rg_igeneration = cpu_to_be64(rgd->rd_igeneration); + str->rg_data0 = cpu_to_be64(rgd->rd_data0); + str->rg_data = cpu_to_be32(rgd->rd_data); + str->rg_bitbytes = cpu_to_be32(rgd->rd_bitbytes); + str->rg_crc = 0; + crc = gfs2_disk_hash(buf, sizeof(struct gfs2_rgrp)); + str->rg_crc = cpu_to_be32(crc); + + memset(&str->rg_reserved, 0, sizeof(str->rg_reserved)); + gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, buf); +} + +static int gfs2_rgrp_lvb_valid(struct gfs2_rgrpd *rgd) +{ + struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl; + struct gfs2_rgrp *str = (struct gfs2_rgrp *)rgd->rd_bits[0].bi_bh->b_data; + struct gfs2_sbd *sdp = rgd->rd_sbd; + int valid = 1; + + if (rgl->rl_flags != str->rg_flags) { + fs_warn(sdp, "GFS2: rgd: %llu lvb flag mismatch %u/%u", + (unsigned long long)rgd->rd_addr, + be32_to_cpu(rgl->rl_flags), be32_to_cpu(str->rg_flags)); + valid = 0; + } + if (rgl->rl_free != str->rg_free) { + fs_warn(sdp, "GFS2: rgd: %llu lvb free mismatch %u/%u", + (unsigned long long)rgd->rd_addr, + be32_to_cpu(rgl->rl_free), be32_to_cpu(str->rg_free)); + valid = 0; + } + if (rgl->rl_dinodes != str->rg_dinodes) { + fs_warn(sdp, "GFS2: rgd: %llu lvb dinode mismatch %u/%u", + (unsigned long long)rgd->rd_addr, + be32_to_cpu(rgl->rl_dinodes), + be32_to_cpu(str->rg_dinodes)); + valid = 0; + } + if (rgl->rl_igeneration != str->rg_igeneration) { + fs_warn(sdp, "GFS2: rgd: %llu lvb igen mismatch %llu/%llu", + (unsigned long long)rgd->rd_addr, + (unsigned long long)be64_to_cpu(rgl->rl_igeneration), + (unsigned long long)be64_to_cpu(str->rg_igeneration)); + valid = 0; + } + return valid; +} + +static u32 count_unlinked(struct gfs2_rgrpd *rgd) +{ + struct gfs2_bitmap *bi; + const u32 length = rgd->rd_length; + const u8 *buffer = NULL; + u32 i, goal, count = 0; + + for (i = 0, bi = rgd->rd_bits; i < length; i++, bi++) { + goal = 0; + buffer = bi->bi_bh->b_data + bi->bi_offset; + WARN_ON(!buffer_uptodate(bi->bi_bh)); + while (goal < bi->bi_blocks) { + goal = gfs2_bitfit(buffer, bi->bi_bytes, goal, + GFS2_BLKST_UNLINKED); + if (goal == BFITNOENT) + break; + count++; + goal++; + } + } + + return count; +} + +static void rgrp_set_bitmap_flags(struct gfs2_rgrpd *rgd) +{ + struct gfs2_bitmap *bi; + int x; + + if (rgd->rd_free) { + for (x = 0; x < rgd->rd_length; x++) { + bi = rgd->rd_bits + x; + clear_bit(GBF_FULL, &bi->bi_flags); + } + } else { + for (x = 0; x < rgd->rd_length; x++) { + bi = rgd->rd_bits + x; + set_bit(GBF_FULL, &bi->bi_flags); + } + } +} + +/** + * gfs2_rgrp_go_instantiate - Read in a RG's header and bitmaps + * @gh: the glock holder representing the rgrpd to read in + * + * Read in all of a Resource Group's header and bitmap blocks. + * Caller must eventually call gfs2_rgrp_brelse() to free the bitmaps. + * + * Returns: errno + */ + +int gfs2_rgrp_go_instantiate(struct gfs2_glock *gl) +{ + struct gfs2_rgrpd *rgd = gl->gl_object; + struct gfs2_sbd *sdp = rgd->rd_sbd; + unsigned int length = rgd->rd_length; + struct gfs2_bitmap *bi; + unsigned int x, y; + int error; + + if (rgd->rd_bits[0].bi_bh != NULL) + return 0; + + for (x = 0; x < length; x++) { + bi = rgd->rd_bits + x; + error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, 0, &bi->bi_bh); + if (error) + goto fail; + } + + for (y = length; y--;) { + bi = rgd->rd_bits + y; + error = gfs2_meta_wait(sdp, bi->bi_bh); + if (error) + goto fail; + if (gfs2_metatype_check(sdp, bi->bi_bh, y ? GFS2_METATYPE_RB : + GFS2_METATYPE_RG)) { + error = -EIO; + goto fail; + } + } + + gfs2_rgrp_in(rgd, (rgd->rd_bits[0].bi_bh)->b_data); + rgrp_set_bitmap_flags(rgd); + rgd->rd_flags |= GFS2_RDF_CHECK; + rgd->rd_free_clone = rgd->rd_free; + GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved); + /* max out the rgrp allocation failure point */ + rgd->rd_extfail_pt = rgd->rd_free; + if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic) { + rgd->rd_rgl->rl_unlinked = cpu_to_be32(count_unlinked(rgd)); + gfs2_rgrp_ondisk2lvb(rgd->rd_rgl, + rgd->rd_bits[0].bi_bh->b_data); + } else if (sdp->sd_args.ar_rgrplvb) { + if (!gfs2_rgrp_lvb_valid(rgd)){ + gfs2_consist_rgrpd(rgd); + error = -EIO; + goto fail; + } + if (rgd->rd_rgl->rl_unlinked == 0) + rgd->rd_flags &= ~GFS2_RDF_CHECK; + } + return 0; + +fail: + while (x--) { + bi = rgd->rd_bits + x; + brelse(bi->bi_bh); + bi->bi_bh = NULL; + gfs2_assert_warn(sdp, !bi->bi_clone); + } + return error; +} + +static int update_rgrp_lvb(struct gfs2_rgrpd *rgd, struct gfs2_holder *gh) +{ + u32 rl_flags; + + if (!test_bit(GLF_INSTANTIATE_NEEDED, &gh->gh_gl->gl_flags)) + return 0; + + if (cpu_to_be32(GFS2_MAGIC) != rgd->rd_rgl->rl_magic) + return gfs2_instantiate(gh); + + rl_flags = be32_to_cpu(rgd->rd_rgl->rl_flags); + rl_flags &= ~GFS2_RDF_MASK; + rgd->rd_flags &= GFS2_RDF_MASK; + rgd->rd_flags |= (rl_flags | GFS2_RDF_CHECK); + if (rgd->rd_rgl->rl_unlinked == 0) + rgd->rd_flags &= ~GFS2_RDF_CHECK; + rgd->rd_free = be32_to_cpu(rgd->rd_rgl->rl_free); + rgrp_set_bitmap_flags(rgd); + rgd->rd_free_clone = rgd->rd_free; + GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved); + /* max out the rgrp allocation failure point */ + rgd->rd_extfail_pt = rgd->rd_free; + rgd->rd_dinodes = be32_to_cpu(rgd->rd_rgl->rl_dinodes); + rgd->rd_igeneration = be64_to_cpu(rgd->rd_rgl->rl_igeneration); + return 0; +} + +/** + * gfs2_rgrp_brelse - Release RG bitmaps read in with gfs2_rgrp_bh_get() + * @rgd: The resource group + * + */ + +void gfs2_rgrp_brelse(struct gfs2_rgrpd *rgd) +{ + int x, length = rgd->rd_length; + + for (x = 0; x < length; x++) { + struct gfs2_bitmap *bi = rgd->rd_bits + x; + if (bi->bi_bh) { + brelse(bi->bi_bh); + bi->bi_bh = NULL; + } + } + set_bit(GLF_INSTANTIATE_NEEDED, &rgd->rd_gl->gl_flags); +} + +int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset, + struct buffer_head *bh, + const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed) +{ + struct super_block *sb = sdp->sd_vfs; + u64 blk; + sector_t start = 0; + sector_t nr_blks = 0; + int rv = -EIO; + unsigned int x; + u32 trimmed = 0; + u8 diff; + + for (x = 0; x < bi->bi_bytes; x++) { + const u8 *clone = bi->bi_clone ? bi->bi_clone : bi->bi_bh->b_data; + clone += bi->bi_offset; + clone += x; + if (bh) { + const u8 *orig = bh->b_data + bi->bi_offset + x; + diff = ~(*orig | (*orig >> 1)) & (*clone | (*clone >> 1)); + } else { + diff = ~(*clone | (*clone >> 1)); + } + diff &= 0x55; + if (diff == 0) + continue; + blk = offset + ((bi->bi_start + x) * GFS2_NBBY); + while(diff) { + if (diff & 1) { + if (nr_blks == 0) + goto start_new_extent; + if ((start + nr_blks) != blk) { + if (nr_blks >= minlen) { + rv = sb_issue_discard(sb, + start, nr_blks, + GFP_NOFS, 0); + if (rv) + goto fail; + trimmed += nr_blks; + } + nr_blks = 0; +start_new_extent: + start = blk; + } + nr_blks++; + } + diff >>= 2; + blk++; + } + } + if (nr_blks >= minlen) { + rv = sb_issue_discard(sb, start, nr_blks, GFP_NOFS, 0); + if (rv) + goto fail; + trimmed += nr_blks; + } + if (ptrimmed) + *ptrimmed = trimmed; + return 0; + +fail: + if (sdp->sd_args.ar_discard) + fs_warn(sdp, "error %d on discard request, turning discards off for this filesystem\n", rv); + sdp->sd_args.ar_discard = 0; + return rv; +} + +/** + * gfs2_fitrim - Generate discard requests for unused bits of the filesystem + * @filp: Any file on the filesystem + * @argp: Pointer to the arguments (also used to pass result) + * + * Returns: 0 on success, otherwise error code + */ + +int gfs2_fitrim(struct file *filp, void __user *argp) +{ + struct inode *inode = file_inode(filp); + struct gfs2_sbd *sdp = GFS2_SB(inode); + struct block_device *bdev = sdp->sd_vfs->s_bdev; + struct buffer_head *bh; + struct gfs2_rgrpd *rgd; + struct gfs2_rgrpd *rgd_end; + struct gfs2_holder gh; + struct fstrim_range r; + int ret = 0; + u64 amt; + u64 trimmed = 0; + u64 start, end, minlen; + unsigned int x; + unsigned bs_shift = sdp->sd_sb.sb_bsize_shift; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) + return -EROFS; + + if (!bdev_max_discard_sectors(bdev)) + return -EOPNOTSUPP; + + if (copy_from_user(&r, argp, sizeof(r))) + return -EFAULT; + + ret = gfs2_rindex_update(sdp); + if (ret) + return ret; + + start = r.start >> bs_shift; + end = start + (r.len >> bs_shift); + minlen = max_t(u64, r.minlen, sdp->sd_sb.sb_bsize); + minlen = max_t(u64, minlen, bdev_discard_granularity(bdev)) >> bs_shift; + + if (end <= start || minlen > sdp->sd_max_rg_data) + return -EINVAL; + + rgd = gfs2_blk2rgrpd(sdp, start, 0); + rgd_end = gfs2_blk2rgrpd(sdp, end, 0); + + if ((gfs2_rgrpd_get_first(sdp) == gfs2_rgrpd_get_next(rgd_end)) + && (start > rgd_end->rd_data0 + rgd_end->rd_data)) + return -EINVAL; /* start is beyond the end of the fs */ + + while (1) { + + ret = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, + LM_FLAG_NODE_SCOPE, &gh); + if (ret) + goto out; + + if (!(rgd->rd_flags & GFS2_RGF_TRIMMED)) { + /* Trim each bitmap in the rgrp */ + for (x = 0; x < rgd->rd_length; x++) { + struct gfs2_bitmap *bi = rgd->rd_bits + x; + rgrp_lock_local(rgd); + ret = gfs2_rgrp_send_discards(sdp, + rgd->rd_data0, NULL, bi, minlen, + &amt); + rgrp_unlock_local(rgd); + if (ret) { + gfs2_glock_dq_uninit(&gh); + goto out; + } + trimmed += amt; + } + + /* Mark rgrp as having been trimmed */ + ret = gfs2_trans_begin(sdp, RES_RG_HDR, 0); + if (ret == 0) { + bh = rgd->rd_bits[0].bi_bh; + rgrp_lock_local(rgd); + rgd->rd_flags |= GFS2_RGF_TRIMMED; + gfs2_trans_add_meta(rgd->rd_gl, bh); + gfs2_rgrp_out(rgd, bh->b_data); + rgrp_unlock_local(rgd); + gfs2_trans_end(sdp); + } + } + gfs2_glock_dq_uninit(&gh); + + if (rgd == rgd_end) + break; + + rgd = gfs2_rgrpd_get_next(rgd); + } + +out: + r.len = trimmed << bs_shift; + if (copy_to_user(argp, &r, sizeof(r))) + return -EFAULT; + + return ret; +} + +/** + * rs_insert - insert a new multi-block reservation into the rgrp's rb_tree + * @ip: the inode structure + * + */ +static void rs_insert(struct gfs2_inode *ip) +{ + struct rb_node **newn, *parent = NULL; + int rc; + struct gfs2_blkreserv *rs = &ip->i_res; + struct gfs2_rgrpd *rgd = rs->rs_rgd; + + BUG_ON(gfs2_rs_active(rs)); + + spin_lock(&rgd->rd_rsspin); + newn = &rgd->rd_rstree.rb_node; + while (*newn) { + struct gfs2_blkreserv *cur = + rb_entry(*newn, struct gfs2_blkreserv, rs_node); + + parent = *newn; + rc = rs_cmp(rs->rs_start, rs->rs_requested, cur); + if (rc > 0) + newn = &((*newn)->rb_right); + else if (rc < 0) + newn = &((*newn)->rb_left); + else { + spin_unlock(&rgd->rd_rsspin); + WARN_ON(1); + return; + } + } + + rb_link_node(&rs->rs_node, parent, newn); + rb_insert_color(&rs->rs_node, &rgd->rd_rstree); + + /* Do our rgrp accounting for the reservation */ + rgd->rd_requested += rs->rs_requested; /* blocks requested */ + spin_unlock(&rgd->rd_rsspin); + trace_gfs2_rs(rs, TRACE_RS_INSERT); +} + +/** + * rgd_free - return the number of free blocks we can allocate + * @rgd: the resource group + * @rs: The reservation to free + * + * This function returns the number of free blocks for an rgrp. + * That's the clone-free blocks (blocks that are free, not including those + * still being used for unlinked files that haven't been deleted.) + * + * It also subtracts any blocks reserved by someone else, but does not + * include free blocks that are still part of our current reservation, + * because obviously we can (and will) allocate them. + */ +static inline u32 rgd_free(struct gfs2_rgrpd *rgd, struct gfs2_blkreserv *rs) +{ + u32 tot_reserved, tot_free; + + if (WARN_ON_ONCE(rgd->rd_requested < rs->rs_requested)) + return 0; + tot_reserved = rgd->rd_requested - rs->rs_requested; + + if (rgd->rd_free_clone < tot_reserved) + tot_reserved = 0; + + tot_free = rgd->rd_free_clone - tot_reserved; + + return tot_free; +} + +/** + * rg_mblk_search - find a group of multiple free blocks to form a reservation + * @rgd: the resource group descriptor + * @ip: pointer to the inode for which we're reserving blocks + * @ap: the allocation parameters + * + */ + +static void rg_mblk_search(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip, + const struct gfs2_alloc_parms *ap) +{ + struct gfs2_rbm rbm = { .rgd = rgd, }; + u64 goal; + struct gfs2_blkreserv *rs = &ip->i_res; + u32 extlen; + u32 free_blocks, blocks_available; + int ret; + struct inode *inode = &ip->i_inode; + + spin_lock(&rgd->rd_rsspin); + free_blocks = rgd_free(rgd, rs); + if (rgd->rd_free_clone < rgd->rd_requested) + free_blocks = 0; + blocks_available = rgd->rd_free_clone - rgd->rd_reserved; + if (rgd == rs->rs_rgd) + blocks_available += rs->rs_reserved; + spin_unlock(&rgd->rd_rsspin); + + if (S_ISDIR(inode->i_mode)) + extlen = 1; + else { + extlen = max_t(u32, atomic_read(&ip->i_sizehint), ap->target); + extlen = clamp(extlen, (u32)RGRP_RSRV_MINBLKS, free_blocks); + } + if (free_blocks < extlen || blocks_available < extlen) + return; + + /* Find bitmap block that contains bits for goal block */ + if (rgrp_contains_block(rgd, ip->i_goal)) + goal = ip->i_goal; + else + goal = rgd->rd_last_alloc + rgd->rd_data0; + + if (WARN_ON(gfs2_rbm_from_block(&rbm, goal))) + return; + + ret = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &extlen, &ip->i_res, true); + if (ret == 0) { + rs->rs_start = gfs2_rbm_to_block(&rbm); + rs->rs_requested = extlen; + rs_insert(ip); + } else { + if (goal == rgd->rd_last_alloc + rgd->rd_data0) + rgd->rd_last_alloc = 0; + } +} + +/** + * gfs2_next_unreserved_block - Return next block that is not reserved + * @rgd: The resource group + * @block: The starting block + * @length: The required length + * @ignore_rs: Reservation to ignore + * + * If the block does not appear in any reservation, then return the + * block number unchanged. If it does appear in the reservation, then + * keep looking through the tree of reservations in order to find the + * first block number which is not reserved. + */ + +static u64 gfs2_next_unreserved_block(struct gfs2_rgrpd *rgd, u64 block, + u32 length, + struct gfs2_blkreserv *ignore_rs) +{ + struct gfs2_blkreserv *rs; + struct rb_node *n; + int rc; + + spin_lock(&rgd->rd_rsspin); + n = rgd->rd_rstree.rb_node; + while (n) { + rs = rb_entry(n, struct gfs2_blkreserv, rs_node); + rc = rs_cmp(block, length, rs); + if (rc < 0) + n = n->rb_left; + else if (rc > 0) + n = n->rb_right; + else + break; + } + + if (n) { + while (rs_cmp(block, length, rs) == 0 && rs != ignore_rs) { + block = rs->rs_start + rs->rs_requested; + n = n->rb_right; + if (n == NULL) + break; + rs = rb_entry(n, struct gfs2_blkreserv, rs_node); + } + } + + spin_unlock(&rgd->rd_rsspin); + return block; +} + +/** + * gfs2_reservation_check_and_update - Check for reservations during block alloc + * @rbm: The current position in the resource group + * @rs: Our own reservation + * @minext: The minimum extent length + * @maxext: A pointer to the maximum extent structure + * + * This checks the current position in the rgrp to see whether there is + * a reservation covering this block. If not then this function is a + * no-op. If there is, then the position is moved to the end of the + * contiguous reservation(s) so that we are pointing at the first + * non-reserved block. + * + * Returns: 0 if no reservation, 1 if @rbm has changed, otherwise an error + */ + +static int gfs2_reservation_check_and_update(struct gfs2_rbm *rbm, + struct gfs2_blkreserv *rs, + u32 minext, + struct gfs2_extent *maxext) +{ + u64 block = gfs2_rbm_to_block(rbm); + u32 extlen = 1; + u64 nblock; + + /* + * If we have a minimum extent length, then skip over any extent + * which is less than the min extent length in size. + */ + if (minext > 1) { + extlen = gfs2_free_extlen(rbm, minext); + if (extlen <= maxext->len) + goto fail; + } + + /* + * Check the extent which has been found against the reservations + * and skip if parts of it are already reserved + */ + nblock = gfs2_next_unreserved_block(rbm->rgd, block, extlen, rs); + if (nblock == block) { + if (!minext || extlen >= minext) + return 0; + + if (extlen > maxext->len) { + maxext->len = extlen; + maxext->rbm = *rbm; + } + } else { + u64 len = nblock - block; + if (len >= (u64)1 << 32) + return -E2BIG; + extlen = len; + } +fail: + if (gfs2_rbm_add(rbm, extlen)) + return -E2BIG; + return 1; +} + +/** + * gfs2_rbm_find - Look for blocks of a particular state + * @rbm: Value/result starting position and final position + * @state: The state which we want to find + * @minext: Pointer to the requested extent length + * This is updated to be the actual reservation size. + * @rs: Our own reservation (NULL to skip checking for reservations) + * @nowrap: Stop looking at the end of the rgrp, rather than wrapping + * around until we've reached the starting point. + * + * Side effects: + * - If looking for free blocks, we set GBF_FULL on each bitmap which + * has no free blocks in it. + * - If looking for free blocks, we set rd_extfail_pt on each rgrp which + * has come up short on a free block search. + * + * Returns: 0 on success, -ENOSPC if there is no block of the requested state + */ + +static int gfs2_rbm_find(struct gfs2_rbm *rbm, u8 state, u32 *minext, + struct gfs2_blkreserv *rs, bool nowrap) +{ + bool scan_from_start = rbm->bii == 0 && rbm->offset == 0; + struct buffer_head *bh; + int last_bii; + u32 offset; + u8 *buffer; + bool wrapped = false; + int ret; + struct gfs2_bitmap *bi; + struct gfs2_extent maxext = { .rbm.rgd = rbm->rgd, }; + + /* + * Determine the last bitmap to search. If we're not starting at the + * beginning of a bitmap, we need to search that bitmap twice to scan + * the entire resource group. + */ + last_bii = rbm->bii - (rbm->offset == 0); + + while(1) { + bi = rbm_bi(rbm); + if (test_bit(GBF_FULL, &bi->bi_flags) && + (state == GFS2_BLKST_FREE)) + goto next_bitmap; + + bh = bi->bi_bh; + buffer = bh->b_data + bi->bi_offset; + WARN_ON(!buffer_uptodate(bh)); + if (state != GFS2_BLKST_UNLINKED && bi->bi_clone) + buffer = bi->bi_clone + bi->bi_offset; + offset = gfs2_bitfit(buffer, bi->bi_bytes, rbm->offset, state); + if (offset == BFITNOENT) { + if (state == GFS2_BLKST_FREE && rbm->offset == 0) + set_bit(GBF_FULL, &bi->bi_flags); + goto next_bitmap; + } + rbm->offset = offset; + if (!rs || !minext) + return 0; + + ret = gfs2_reservation_check_and_update(rbm, rs, *minext, + &maxext); + if (ret == 0) + return 0; + if (ret > 0) + goto next_iter; + if (ret == -E2BIG) { + rbm->bii = 0; + rbm->offset = 0; + goto res_covered_end_of_rgrp; + } + return ret; + +next_bitmap: /* Find next bitmap in the rgrp */ + rbm->offset = 0; + rbm->bii++; + if (rbm->bii == rbm->rgd->rd_length) + rbm->bii = 0; +res_covered_end_of_rgrp: + if (rbm->bii == 0) { + if (wrapped) + break; + wrapped = true; + if (nowrap) + break; + } +next_iter: + /* Have we scanned the entire resource group? */ + if (wrapped && rbm->bii > last_bii) + break; + } + + if (state != GFS2_BLKST_FREE) + return -ENOSPC; + + /* If the extent was too small, and it's smaller than the smallest + to have failed before, remember for future reference that it's + useless to search this rgrp again for this amount or more. */ + if (wrapped && (scan_from_start || rbm->bii > last_bii) && + *minext < rbm->rgd->rd_extfail_pt) + rbm->rgd->rd_extfail_pt = *minext - 1; + + /* If the maximum extent we found is big enough to fulfill the + minimum requirements, use it anyway. */ + if (maxext.len) { + *rbm = maxext.rbm; + *minext = maxext.len; + return 0; + } + + return -ENOSPC; +} + +/** + * try_rgrp_unlink - Look for any unlinked, allocated, but unused inodes + * @rgd: The rgrp + * @last_unlinked: block address of the last dinode we unlinked + * @skip: block address we should explicitly not unlink + * + * Returns: 0 if no error + * The inode, if one has been found, in inode. + */ + +static void try_rgrp_unlink(struct gfs2_rgrpd *rgd, u64 *last_unlinked, u64 skip) +{ + u64 block; + struct gfs2_sbd *sdp = rgd->rd_sbd; + struct gfs2_glock *gl; + struct gfs2_inode *ip; + int error; + int found = 0; + struct gfs2_rbm rbm = { .rgd = rgd, .bii = 0, .offset = 0 }; + + while (1) { + error = gfs2_rbm_find(&rbm, GFS2_BLKST_UNLINKED, NULL, NULL, + true); + if (error == -ENOSPC) + break; + if (WARN_ON_ONCE(error)) + break; + + block = gfs2_rbm_to_block(&rbm); + if (gfs2_rbm_from_block(&rbm, block + 1)) + break; + if (*last_unlinked != NO_BLOCK && block <= *last_unlinked) + continue; + if (block == skip) + continue; + *last_unlinked = block; + + error = gfs2_glock_get(sdp, block, &gfs2_iopen_glops, CREATE, &gl); + if (error) + continue; + + /* If the inode is already in cache, we can ignore it here + * because the existing inode disposal code will deal with + * it when all refs have gone away. Accessing gl_object like + * this is not safe in general. Here it is ok because we do + * not dereference the pointer, and we only need an approx + * answer to whether it is NULL or not. + */ + ip = gl->gl_object; + + if (ip || !gfs2_queue_delete_work(gl, 0)) + gfs2_glock_put(gl); + else + found++; + + /* Limit reclaim to sensible number of tasks */ + if (found > NR_CPUS) + return; + } + + rgd->rd_flags &= ~GFS2_RDF_CHECK; + return; +} + +/** + * gfs2_rgrp_congested - Use stats to figure out whether an rgrp is congested + * @rgd: The rgrp in question + * @loops: An indication of how picky we can be (0=very, 1=less so) + * + * This function uses the recently added glock statistics in order to + * figure out whether a parciular resource group is suffering from + * contention from multiple nodes. This is done purely on the basis + * of timings, since this is the only data we have to work with and + * our aim here is to reject a resource group which is highly contended + * but (very important) not to do this too often in order to ensure that + * we do not land up introducing fragmentation by changing resource + * groups when not actually required. + * + * The calculation is fairly simple, we want to know whether the SRTTB + * (i.e. smoothed round trip time for blocking operations) to acquire + * the lock for this rgrp's glock is significantly greater than the + * time taken for resource groups on average. We introduce a margin in + * the form of the variable @var which is computed as the sum of the two + * respective variences, and multiplied by a factor depending on @loops + * and whether we have a lot of data to base the decision on. This is + * then tested against the square difference of the means in order to + * decide whether the result is statistically significant or not. + * + * Returns: A boolean verdict on the congestion status + */ + +static bool gfs2_rgrp_congested(const struct gfs2_rgrpd *rgd, int loops) +{ + const struct gfs2_glock *gl = rgd->rd_gl; + const struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; + struct gfs2_lkstats *st; + u64 r_dcount, l_dcount; + u64 l_srttb, a_srttb = 0; + s64 srttb_diff; + u64 sqr_diff; + u64 var; + int cpu, nonzero = 0; + + preempt_disable(); + for_each_present_cpu(cpu) { + st = &per_cpu_ptr(sdp->sd_lkstats, cpu)->lkstats[LM_TYPE_RGRP]; + if (st->stats[GFS2_LKS_SRTTB]) { + a_srttb += st->stats[GFS2_LKS_SRTTB]; + nonzero++; + } + } + st = &this_cpu_ptr(sdp->sd_lkstats)->lkstats[LM_TYPE_RGRP]; + if (nonzero) + do_div(a_srttb, nonzero); + r_dcount = st->stats[GFS2_LKS_DCOUNT]; + var = st->stats[GFS2_LKS_SRTTVARB] + + gl->gl_stats.stats[GFS2_LKS_SRTTVARB]; + preempt_enable(); + + l_srttb = gl->gl_stats.stats[GFS2_LKS_SRTTB]; + l_dcount = gl->gl_stats.stats[GFS2_LKS_DCOUNT]; + + if ((l_dcount < 1) || (r_dcount < 1) || (a_srttb == 0)) + return false; + + srttb_diff = a_srttb - l_srttb; + sqr_diff = srttb_diff * srttb_diff; + + var *= 2; + if (l_dcount < 8 || r_dcount < 8) + var *= 2; + if (loops == 1) + var *= 2; + + return ((srttb_diff < 0) && (sqr_diff > var)); +} + +/** + * gfs2_rgrp_used_recently + * @rs: The block reservation with the rgrp to test + * @msecs: The time limit in milliseconds + * + * Returns: True if the rgrp glock has been used within the time limit + */ +static bool gfs2_rgrp_used_recently(const struct gfs2_blkreserv *rs, + u64 msecs) +{ + u64 tdiff; + + tdiff = ktime_to_ns(ktime_sub(ktime_get_real(), + rs->rs_rgd->rd_gl->gl_dstamp)); + + return tdiff > (msecs * 1000 * 1000); +} + +static u32 gfs2_orlov_skip(const struct gfs2_inode *ip) +{ + const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + u32 skip; + + get_random_bytes(&skip, sizeof(skip)); + return skip % sdp->sd_rgrps; +} + +static bool gfs2_select_rgrp(struct gfs2_rgrpd **pos, const struct gfs2_rgrpd *begin) +{ + struct gfs2_rgrpd *rgd = *pos; + struct gfs2_sbd *sdp = rgd->rd_sbd; + + rgd = gfs2_rgrpd_get_next(rgd); + if (rgd == NULL) + rgd = gfs2_rgrpd_get_first(sdp); + *pos = rgd; + if (rgd != begin) /* If we didn't wrap */ + return true; + return false; +} + +/** + * fast_to_acquire - determine if a resource group will be fast to acquire + * @rgd: The rgrp + * + * If this is one of our preferred rgrps, it should be quicker to acquire, + * because we tried to set ourselves up as dlm lock master. + */ +static inline int fast_to_acquire(struct gfs2_rgrpd *rgd) +{ + struct gfs2_glock *gl = rgd->rd_gl; + + if (gl->gl_state != LM_ST_UNLOCKED && list_empty(&gl->gl_holders) && + !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && + !test_bit(GLF_DEMOTE, &gl->gl_flags)) + return 1; + if (rgd->rd_flags & GFS2_RDF_PREFERRED) + return 1; + return 0; +} + +/** + * gfs2_inplace_reserve - Reserve space in the filesystem + * @ip: the inode to reserve space for + * @ap: the allocation parameters + * + * We try our best to find an rgrp that has at least ap->target blocks + * available. After a couple of passes (loops == 2), the prospects of finding + * such an rgrp diminish. At this stage, we return the first rgrp that has + * at least ap->min_target blocks available. + * + * Returns: 0 on success, + * -ENOMEM if a suitable rgrp can't be found + * errno otherwise + */ + +int gfs2_inplace_reserve(struct gfs2_inode *ip, struct gfs2_alloc_parms *ap) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + struct gfs2_rgrpd *begin = NULL; + struct gfs2_blkreserv *rs = &ip->i_res; + int error = 0, flags = LM_FLAG_NODE_SCOPE; + bool rg_locked; + u64 last_unlinked = NO_BLOCK; + u32 target = ap->target; + int loops = 0; + u32 free_blocks, blocks_available, skip = 0; + + BUG_ON(rs->rs_reserved); + + if (sdp->sd_args.ar_rgrplvb) + flags |= GL_SKIP; + if (gfs2_assert_warn(sdp, target)) + return -EINVAL; + if (gfs2_rs_active(rs)) { + begin = rs->rs_rgd; + } else if (rs->rs_rgd && + rgrp_contains_block(rs->rs_rgd, ip->i_goal)) { + begin = rs->rs_rgd; + } else { + check_and_update_goal(ip); + rs->rs_rgd = begin = gfs2_blk2rgrpd(sdp, ip->i_goal, 1); + } + if (S_ISDIR(ip->i_inode.i_mode) && (ap->aflags & GFS2_AF_ORLOV)) + skip = gfs2_orlov_skip(ip); + if (rs->rs_rgd == NULL) + return -EBADSLT; + + while (loops < 3) { + struct gfs2_rgrpd *rgd; + + rg_locked = gfs2_glock_is_locked_by_me(rs->rs_rgd->rd_gl); + if (rg_locked) { + rgrp_lock_local(rs->rs_rgd); + } else { + if (skip && skip--) + goto next_rgrp; + if (!gfs2_rs_active(rs)) { + if (loops == 0 && + !fast_to_acquire(rs->rs_rgd)) + goto next_rgrp; + if ((loops < 2) && + gfs2_rgrp_used_recently(rs, 1000) && + gfs2_rgrp_congested(rs->rs_rgd, loops)) + goto next_rgrp; + } + error = gfs2_glock_nq_init(rs->rs_rgd->rd_gl, + LM_ST_EXCLUSIVE, flags, + &ip->i_rgd_gh); + if (unlikely(error)) + return error; + rgrp_lock_local(rs->rs_rgd); + if (!gfs2_rs_active(rs) && (loops < 2) && + gfs2_rgrp_congested(rs->rs_rgd, loops)) + goto skip_rgrp; + if (sdp->sd_args.ar_rgrplvb) { + error = update_rgrp_lvb(rs->rs_rgd, + &ip->i_rgd_gh); + if (unlikely(error)) { + rgrp_unlock_local(rs->rs_rgd); + gfs2_glock_dq_uninit(&ip->i_rgd_gh); + return error; + } + } + } + + /* Skip unusable resource groups */ + if ((rs->rs_rgd->rd_flags & (GFS2_RGF_NOALLOC | + GFS2_RDF_ERROR)) || + (loops == 0 && target > rs->rs_rgd->rd_extfail_pt)) + goto skip_rgrp; + + if (sdp->sd_args.ar_rgrplvb) { + error = gfs2_instantiate(&ip->i_rgd_gh); + if (error) + goto skip_rgrp; + } + + /* Get a reservation if we don't already have one */ + if (!gfs2_rs_active(rs)) + rg_mblk_search(rs->rs_rgd, ip, ap); + + /* Skip rgrps when we can't get a reservation on first pass */ + if (!gfs2_rs_active(rs) && (loops < 1)) + goto check_rgrp; + + /* If rgrp has enough free space, use it */ + rgd = rs->rs_rgd; + spin_lock(&rgd->rd_rsspin); + free_blocks = rgd_free(rgd, rs); + blocks_available = rgd->rd_free_clone - rgd->rd_reserved; + if (free_blocks < target || blocks_available < target) { + spin_unlock(&rgd->rd_rsspin); + goto check_rgrp; + } + rs->rs_reserved = ap->target; + if (rs->rs_reserved > blocks_available) + rs->rs_reserved = blocks_available; + rgd->rd_reserved += rs->rs_reserved; + spin_unlock(&rgd->rd_rsspin); + rgrp_unlock_local(rs->rs_rgd); + return 0; +check_rgrp: + /* Check for unlinked inodes which can be reclaimed */ + if (rs->rs_rgd->rd_flags & GFS2_RDF_CHECK) + try_rgrp_unlink(rs->rs_rgd, &last_unlinked, + ip->i_no_addr); +skip_rgrp: + rgrp_unlock_local(rs->rs_rgd); + + /* Drop reservation, if we couldn't use reserved rgrp */ + if (gfs2_rs_active(rs)) + gfs2_rs_deltree(rs); + + /* Unlock rgrp if required */ + if (!rg_locked) + gfs2_glock_dq_uninit(&ip->i_rgd_gh); +next_rgrp: + /* Find the next rgrp, and continue looking */ + if (gfs2_select_rgrp(&rs->rs_rgd, begin)) + continue; + if (skip) + continue; + + /* If we've scanned all the rgrps, but found no free blocks + * then this checks for some less likely conditions before + * trying again. + */ + loops++; + /* Check that fs hasn't grown if writing to rindex */ + if (ip == GFS2_I(sdp->sd_rindex) && !sdp->sd_rindex_uptodate) { + error = gfs2_ri_update(ip); + if (error) + return error; + } + /* Flushing the log may release space */ + if (loops == 2) { + if (ap->min_target) + target = ap->min_target; + gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL | + GFS2_LFC_INPLACE_RESERVE); + } + } + + return -ENOSPC; +} + +/** + * gfs2_inplace_release - release an inplace reservation + * @ip: the inode the reservation was taken out on + * + * Release a reservation made by gfs2_inplace_reserve(). + */ + +void gfs2_inplace_release(struct gfs2_inode *ip) +{ + struct gfs2_blkreserv *rs = &ip->i_res; + + if (rs->rs_reserved) { + struct gfs2_rgrpd *rgd = rs->rs_rgd; + + spin_lock(&rgd->rd_rsspin); + GLOCK_BUG_ON(rgd->rd_gl, rgd->rd_reserved < rs->rs_reserved); + rgd->rd_reserved -= rs->rs_reserved; + spin_unlock(&rgd->rd_rsspin); + rs->rs_reserved = 0; + } + if (gfs2_holder_initialized(&ip->i_rgd_gh)) + gfs2_glock_dq_uninit(&ip->i_rgd_gh); +} + +/** + * gfs2_alloc_extent - allocate an extent from a given bitmap + * @rbm: the resource group information + * @dinode: TRUE if the first block we allocate is for a dinode + * @n: The extent length (value/result) + * + * Add the bitmap buffer to the transaction. + * Set the found bits to @new_state to change block's allocation state. + */ +static void gfs2_alloc_extent(const struct gfs2_rbm *rbm, bool dinode, + unsigned int *n) +{ + struct gfs2_rbm pos = { .rgd = rbm->rgd, }; + const unsigned int elen = *n; + u64 block; + int ret; + + *n = 1; + block = gfs2_rbm_to_block(rbm); + gfs2_trans_add_meta(rbm->rgd->rd_gl, rbm_bi(rbm)->bi_bh); + gfs2_setbit(rbm, true, dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED); + block++; + while (*n < elen) { + ret = gfs2_rbm_from_block(&pos, block); + if (ret || gfs2_testbit(&pos, true) != GFS2_BLKST_FREE) + break; + gfs2_trans_add_meta(pos.rgd->rd_gl, rbm_bi(&pos)->bi_bh); + gfs2_setbit(&pos, true, GFS2_BLKST_USED); + (*n)++; + block++; + } +} + +/** + * rgblk_free - Change alloc state of given block(s) + * @sdp: the filesystem + * @rgd: the resource group the blocks are in + * @bstart: the start of a run of blocks to free + * @blen: the length of the block run (all must lie within ONE RG!) + * @new_state: GFS2_BLKST_XXX the after-allocation block state + */ + +static void rgblk_free(struct gfs2_sbd *sdp, struct gfs2_rgrpd *rgd, + u64 bstart, u32 blen, unsigned char new_state) +{ + struct gfs2_rbm rbm; + struct gfs2_bitmap *bi, *bi_prev = NULL; + + rbm.rgd = rgd; + if (WARN_ON_ONCE(gfs2_rbm_from_block(&rbm, bstart))) + return; + while (blen--) { + bi = rbm_bi(&rbm); + if (bi != bi_prev) { + if (!bi->bi_clone) { + bi->bi_clone = kmalloc(bi->bi_bh->b_size, + GFP_NOFS | __GFP_NOFAIL); + memcpy(bi->bi_clone + bi->bi_offset, + bi->bi_bh->b_data + bi->bi_offset, + bi->bi_bytes); + } + gfs2_trans_add_meta(rbm.rgd->rd_gl, bi->bi_bh); + bi_prev = bi; + } + gfs2_setbit(&rbm, false, new_state); + gfs2_rbm_add(&rbm, 1); + } +} + +/** + * gfs2_rgrp_dump - print out an rgrp + * @seq: The iterator + * @rgd: The rgrp in question + * @fs_id_buf: pointer to file system id (if requested) + * + */ + +void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_rgrpd *rgd, + const char *fs_id_buf) +{ + struct gfs2_blkreserv *trs; + const struct rb_node *n; + + spin_lock(&rgd->rd_rsspin); + gfs2_print_dbg(seq, "%s R: n:%llu f:%02x b:%u/%u i:%u q:%u r:%u e:%u\n", + fs_id_buf, + (unsigned long long)rgd->rd_addr, rgd->rd_flags, + rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes, + rgd->rd_requested, rgd->rd_reserved, rgd->rd_extfail_pt); + if (rgd->rd_sbd->sd_args.ar_rgrplvb && rgd->rd_rgl) { + struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl; + + gfs2_print_dbg(seq, "%s L: f:%02x b:%u i:%u\n", fs_id_buf, + be32_to_cpu(rgl->rl_flags), + be32_to_cpu(rgl->rl_free), + be32_to_cpu(rgl->rl_dinodes)); + } + for (n = rb_first(&rgd->rd_rstree); n; n = rb_next(&trs->rs_node)) { + trs = rb_entry(n, struct gfs2_blkreserv, rs_node); + dump_rs(seq, trs, fs_id_buf); + } + spin_unlock(&rgd->rd_rsspin); +} + +static void gfs2_rgrp_error(struct gfs2_rgrpd *rgd) +{ + struct gfs2_sbd *sdp = rgd->rd_sbd; + char fs_id_buf[sizeof(sdp->sd_fsname) + 7]; + + fs_warn(sdp, "rgrp %llu has an error, marking it readonly until umount\n", + (unsigned long long)rgd->rd_addr); + fs_warn(sdp, "umount on all nodes and run fsck.gfs2 to fix the error\n"); + sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname); + gfs2_rgrp_dump(NULL, rgd, fs_id_buf); + rgd->rd_flags |= GFS2_RDF_ERROR; +} + +/** + * gfs2_adjust_reservation - Adjust (or remove) a reservation after allocation + * @ip: The inode we have just allocated blocks for + * @rbm: The start of the allocated blocks + * @len: The extent length + * + * Adjusts a reservation after an allocation has taken place. If the + * reservation does not match the allocation, or if it is now empty + * then it is removed. + */ + +static void gfs2_adjust_reservation(struct gfs2_inode *ip, + const struct gfs2_rbm *rbm, unsigned len) +{ + struct gfs2_blkreserv *rs = &ip->i_res; + struct gfs2_rgrpd *rgd = rbm->rgd; + + BUG_ON(rs->rs_reserved < len); + rs->rs_reserved -= len; + if (gfs2_rs_active(rs)) { + u64 start = gfs2_rbm_to_block(rbm); + + if (rs->rs_start == start) { + unsigned int rlen; + + rs->rs_start += len; + rlen = min(rs->rs_requested, len); + rs->rs_requested -= rlen; + rgd->rd_requested -= rlen; + trace_gfs2_rs(rs, TRACE_RS_CLAIM); + if (rs->rs_start < rgd->rd_data0 + rgd->rd_data && + rs->rs_requested) + return; + /* We used up our block reservation, so we should + reserve more blocks next time. */ + atomic_add(RGRP_RSRV_ADDBLKS, &ip->i_sizehint); + } + __rs_deltree(rs); + } +} + +/** + * gfs2_set_alloc_start - Set starting point for block allocation + * @rbm: The rbm which will be set to the required location + * @ip: The gfs2 inode + * @dinode: Flag to say if allocation includes a new inode + * + * This sets the starting point from the reservation if one is active + * otherwise it falls back to guessing a start point based on the + * inode's goal block or the last allocation point in the rgrp. + */ + +static void gfs2_set_alloc_start(struct gfs2_rbm *rbm, + const struct gfs2_inode *ip, bool dinode) +{ + u64 goal; + + if (gfs2_rs_active(&ip->i_res)) { + goal = ip->i_res.rs_start; + } else { + if (!dinode && rgrp_contains_block(rbm->rgd, ip->i_goal)) + goal = ip->i_goal; + else + goal = rbm->rgd->rd_last_alloc + rbm->rgd->rd_data0; + } + if (WARN_ON_ONCE(gfs2_rbm_from_block(rbm, goal))) { + rbm->bii = 0; + rbm->offset = 0; + } +} + +/** + * gfs2_alloc_blocks - Allocate one or more blocks of data and/or a dinode + * @ip: the inode to allocate the block for + * @bn: Used to return the starting block number + * @nblocks: requested number of blocks/extent length (value/result) + * @dinode: 1 if we're allocating a dinode block, else 0 + * @generation: the generation number of the inode + * + * Returns: 0 or error + */ + +int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *nblocks, + bool dinode, u64 *generation) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + struct buffer_head *dibh; + struct gfs2_rbm rbm = { .rgd = ip->i_res.rs_rgd, }; + u64 block; /* block, within the file system scope */ + u32 minext = 1; + int error = -ENOSPC; + + BUG_ON(ip->i_res.rs_reserved < *nblocks); + + rgrp_lock_local(rbm.rgd); + if (gfs2_rs_active(&ip->i_res)) { + gfs2_set_alloc_start(&rbm, ip, dinode); + error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &minext, &ip->i_res, false); + } + if (error == -ENOSPC) { + gfs2_set_alloc_start(&rbm, ip, dinode); + error = gfs2_rbm_find(&rbm, GFS2_BLKST_FREE, &minext, NULL, false); + } + + /* Since all blocks are reserved in advance, this shouldn't happen */ + if (error) { + fs_warn(sdp, "inum=%llu error=%d, nblocks=%u, full=%d fail_pt=%d\n", + (unsigned long long)ip->i_no_addr, error, *nblocks, + test_bit(GBF_FULL, &rbm.rgd->rd_bits->bi_flags), + rbm.rgd->rd_extfail_pt); + goto rgrp_error; + } + + gfs2_alloc_extent(&rbm, dinode, nblocks); + block = gfs2_rbm_to_block(&rbm); + rbm.rgd->rd_last_alloc = block - rbm.rgd->rd_data0; + if (!dinode) { + ip->i_goal = block + *nblocks - 1; + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error == 0) { + struct gfs2_dinode *di = + (struct gfs2_dinode *)dibh->b_data; + gfs2_trans_add_meta(ip->i_gl, dibh); + di->di_goal_meta = di->di_goal_data = + cpu_to_be64(ip->i_goal); + brelse(dibh); + } + } + spin_lock(&rbm.rgd->rd_rsspin); + gfs2_adjust_reservation(ip, &rbm, *nblocks); + if (rbm.rgd->rd_free < *nblocks || rbm.rgd->rd_reserved < *nblocks) { + fs_warn(sdp, "nblocks=%u\n", *nblocks); + spin_unlock(&rbm.rgd->rd_rsspin); + goto rgrp_error; + } + GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_reserved < *nblocks); + GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_free_clone < *nblocks); + GLOCK_BUG_ON(rbm.rgd->rd_gl, rbm.rgd->rd_free < *nblocks); + rbm.rgd->rd_reserved -= *nblocks; + rbm.rgd->rd_free_clone -= *nblocks; + rbm.rgd->rd_free -= *nblocks; + spin_unlock(&rbm.rgd->rd_rsspin); + if (dinode) { + rbm.rgd->rd_dinodes++; + *generation = rbm.rgd->rd_igeneration++; + if (*generation == 0) + *generation = rbm.rgd->rd_igeneration++; + } + + gfs2_trans_add_meta(rbm.rgd->rd_gl, rbm.rgd->rd_bits[0].bi_bh); + gfs2_rgrp_out(rbm.rgd, rbm.rgd->rd_bits[0].bi_bh->b_data); + rgrp_unlock_local(rbm.rgd); + + gfs2_statfs_change(sdp, 0, -(s64)*nblocks, dinode ? 1 : 0); + if (dinode) + gfs2_trans_remove_revoke(sdp, block, *nblocks); + + gfs2_quota_change(ip, *nblocks, ip->i_inode.i_uid, ip->i_inode.i_gid); + + trace_gfs2_block_alloc(ip, rbm.rgd, block, *nblocks, + dinode ? GFS2_BLKST_DINODE : GFS2_BLKST_USED); + *bn = block; + return 0; + +rgrp_error: + rgrp_unlock_local(rbm.rgd); + gfs2_rgrp_error(rbm.rgd); + return -EIO; +} + +/** + * __gfs2_free_blocks - free a contiguous run of block(s) + * @ip: the inode these blocks are being freed from + * @rgd: the resource group the blocks are in + * @bstart: first block of a run of contiguous blocks + * @blen: the length of the block run + * @meta: 1 if the blocks represent metadata + * + */ + +void __gfs2_free_blocks(struct gfs2_inode *ip, struct gfs2_rgrpd *rgd, + u64 bstart, u32 blen, int meta) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + + rgrp_lock_local(rgd); + rgblk_free(sdp, rgd, bstart, blen, GFS2_BLKST_FREE); + trace_gfs2_block_alloc(ip, rgd, bstart, blen, GFS2_BLKST_FREE); + rgd->rd_free += blen; + rgd->rd_flags &= ~GFS2_RGF_TRIMMED; + gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh); + gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data); + rgrp_unlock_local(rgd); + + /* Directories keep their data in the metadata address space */ + if (meta || ip->i_depth || gfs2_is_jdata(ip)) + gfs2_journal_wipe(ip, bstart, blen); +} + +/** + * gfs2_free_meta - free a contiguous run of data block(s) + * @ip: the inode these blocks are being freed from + * @rgd: the resource group the blocks are in + * @bstart: first block of a run of contiguous blocks + * @blen: the length of the block run + * + */ + +void gfs2_free_meta(struct gfs2_inode *ip, struct gfs2_rgrpd *rgd, + u64 bstart, u32 blen) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + + __gfs2_free_blocks(ip, rgd, bstart, blen, 1); + gfs2_statfs_change(sdp, 0, +blen, 0); + gfs2_quota_change(ip, -(s64)blen, ip->i_inode.i_uid, ip->i_inode.i_gid); +} + +void gfs2_unlink_di(struct inode *inode) +{ + struct gfs2_inode *ip = GFS2_I(inode); + struct gfs2_sbd *sdp = GFS2_SB(inode); + struct gfs2_rgrpd *rgd; + u64 blkno = ip->i_no_addr; + + rgd = gfs2_blk2rgrpd(sdp, blkno, true); + if (!rgd) + return; + rgrp_lock_local(rgd); + rgblk_free(sdp, rgd, blkno, 1, GFS2_BLKST_UNLINKED); + trace_gfs2_block_alloc(ip, rgd, blkno, 1, GFS2_BLKST_UNLINKED); + gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh); + gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data); + be32_add_cpu(&rgd->rd_rgl->rl_unlinked, 1); + rgrp_unlock_local(rgd); +} + +void gfs2_free_di(struct gfs2_rgrpd *rgd, struct gfs2_inode *ip) +{ + struct gfs2_sbd *sdp = rgd->rd_sbd; + + rgrp_lock_local(rgd); + rgblk_free(sdp, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE); + if (!rgd->rd_dinodes) + gfs2_consist_rgrpd(rgd); + rgd->rd_dinodes--; + rgd->rd_free++; + + gfs2_trans_add_meta(rgd->rd_gl, rgd->rd_bits[0].bi_bh); + gfs2_rgrp_out(rgd, rgd->rd_bits[0].bi_bh->b_data); + rgrp_unlock_local(rgd); + be32_add_cpu(&rgd->rd_rgl->rl_unlinked, -1); + + gfs2_statfs_change(sdp, 0, +1, -1); + trace_gfs2_block_alloc(ip, rgd, ip->i_no_addr, 1, GFS2_BLKST_FREE); + gfs2_quota_change(ip, -1, ip->i_inode.i_uid, ip->i_inode.i_gid); + gfs2_journal_wipe(ip, ip->i_no_addr, 1); +} + +/** + * gfs2_check_blk_type - Check the type of a block + * @sdp: The superblock + * @no_addr: The block number to check + * @type: The block type we are looking for + * + * The inode glock of @no_addr must be held. The @type to check for is either + * GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED; checking for type GFS2_BLKST_FREE + * or GFS2_BLKST_USED would make no sense. + * + * Returns: 0 if the block type matches the expected type + * -ESTALE if it doesn't match + * or -ve errno if something went wrong while checking + */ + +int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type) +{ + struct gfs2_rgrpd *rgd; + struct gfs2_holder rgd_gh; + struct gfs2_rbm rbm; + int error = -EINVAL; + + rgd = gfs2_blk2rgrpd(sdp, no_addr, 1); + if (!rgd) + goto fail; + + error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh); + if (error) + goto fail; + + rbm.rgd = rgd; + error = gfs2_rbm_from_block(&rbm, no_addr); + if (!WARN_ON_ONCE(error)) { + /* + * No need to take the local resource group lock here; the + * inode glock of @no_addr provides the necessary + * synchronization in case the block is an inode. (In case + * the block is not an inode, the block type will not match + * the @type we are looking for.) + */ + if (gfs2_testbit(&rbm, false) != type) + error = -ESTALE; + } + + gfs2_glock_dq_uninit(&rgd_gh); + +fail: + return error; +} + +/** + * gfs2_rlist_add - add a RG to a list of RGs + * @ip: the inode + * @rlist: the list of resource groups + * @block: the block + * + * Figure out what RG a block belongs to and add that RG to the list + * + * FIXME: Don't use NOFAIL + * + */ + +void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist, + u64 block) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + struct gfs2_rgrpd *rgd; + struct gfs2_rgrpd **tmp; + unsigned int new_space; + unsigned int x; + + if (gfs2_assert_warn(sdp, !rlist->rl_ghs)) + return; + + /* + * The resource group last accessed is kept in the last position. + */ + + if (rlist->rl_rgrps) { + rgd = rlist->rl_rgd[rlist->rl_rgrps - 1]; + if (rgrp_contains_block(rgd, block)) + return; + rgd = gfs2_blk2rgrpd(sdp, block, 1); + } else { + rgd = ip->i_res.rs_rgd; + if (!rgd || !rgrp_contains_block(rgd, block)) + rgd = gfs2_blk2rgrpd(sdp, block, 1); + } + + if (!rgd) { + fs_err(sdp, "rlist_add: no rgrp for block %llu\n", + (unsigned long long)block); + return; + } + + for (x = 0; x < rlist->rl_rgrps; x++) { + if (rlist->rl_rgd[x] == rgd) { + swap(rlist->rl_rgd[x], + rlist->rl_rgd[rlist->rl_rgrps - 1]); + return; + } + } + + if (rlist->rl_rgrps == rlist->rl_space) { + new_space = rlist->rl_space + 10; + + tmp = kcalloc(new_space, sizeof(struct gfs2_rgrpd *), + GFP_NOFS | __GFP_NOFAIL); + + if (rlist->rl_rgd) { + memcpy(tmp, rlist->rl_rgd, + rlist->rl_space * sizeof(struct gfs2_rgrpd *)); + kfree(rlist->rl_rgd); + } + + rlist->rl_space = new_space; + rlist->rl_rgd = tmp; + } + + rlist->rl_rgd[rlist->rl_rgrps++] = rgd; +} + +/** + * gfs2_rlist_alloc - all RGs have been added to the rlist, now allocate + * and initialize an array of glock holders for them + * @rlist: the list of resource groups + * @state: the state we're requesting + * @flags: the modifier flags + * + * FIXME: Don't use NOFAIL + * + */ + +void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, + unsigned int state, u16 flags) +{ + unsigned int x; + + rlist->rl_ghs = kmalloc_array(rlist->rl_rgrps, + sizeof(struct gfs2_holder), + GFP_NOFS | __GFP_NOFAIL); + for (x = 0; x < rlist->rl_rgrps; x++) + gfs2_holder_init(rlist->rl_rgd[x]->rd_gl, state, flags, + &rlist->rl_ghs[x]); +} + +/** + * gfs2_rlist_free - free a resource group list + * @rlist: the list of resource groups + * + */ + +void gfs2_rlist_free(struct gfs2_rgrp_list *rlist) +{ + unsigned int x; + + kfree(rlist->rl_rgd); + + if (rlist->rl_ghs) { + for (x = 0; x < rlist->rl_rgrps; x++) + gfs2_holder_uninit(&rlist->rl_ghs[x]); + kfree(rlist->rl_ghs); + rlist->rl_ghs = NULL; + } +} + +void rgrp_lock_local(struct gfs2_rgrpd *rgd) +{ + mutex_lock(&rgd->rd_mutex); +} + +void rgrp_unlock_local(struct gfs2_rgrpd *rgd) +{ + mutex_unlock(&rgd->rd_mutex); +} |