From: Bob Peterson <[email protected]> This patch implements iomap for block mapping, and switches the block_map function to use it under the covers.
The additional IOMAP_F_BOUNDARY iomap flag indicates when iomap has reached a "metadata boundary" and fetching the next mapping is likely to incur an additional I/O. This flag is used for setting the bh buffer boundary flag. Signed-off-by: Bob Peterson <[email protected]> Signed-off-by: Andreas Gruenbacher <[email protected]> --- fs/gfs2/bmap.c | 249 ++++++++++++++++++++++++++++++++++++-------------- fs/gfs2/bmap.h | 4 + fs/gfs2/trace_gfs2.h | 65 +++++++++++++ include/linux/iomap.h | 3 +- 4 files changed, 250 insertions(+), 71 deletions(-) diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index a431afd..fa33fdc 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -13,6 +13,7 @@ #include <linux/blkdev.h> #include <linux/gfs2_ondisk.h> #include <linux/crc32.h> +#include <linux/iomap.h> #include "gfs2.h" #include "incore.h" @@ -416,7 +417,6 @@ static inline unsigned int gfs2_extent_length(void *start, unsigned int len, __b const __be64 *first = ptr; u64 d = be64_to_cpu(*ptr); - *eob = 0; do { ptr++; if (ptr >= end) @@ -504,10 +504,8 @@ static inline unsigned int hptrs(struct gfs2_sbd *sdp, const unsigned int hgt) * Returns: errno on error */ -static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock, - bool zero_new, struct metapath *mp, - const size_t maxlen, sector_t *dblock, - unsigned *dblks) +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); @@ -515,36 +513,37 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock, 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; - int eob = 0; 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); - *dblock = 0; - *dblks = 0; 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); + 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])); + 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; @@ -560,7 +559,7 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock, /* start of the second part of the function (state machine) */ - blks = *dblks + iblks; + blks = dblks + iblks; i = mp->mp_aheight; do { int error; @@ -617,26 +616,28 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock, break; /* Tree complete, adding data blocks */ case ALLOC_DATA: - BUG_ON(n > *dblks); + 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; + dblks = n; ptr = metapointer(end_of_metadata, mp); - *dblock = bn; + iomap->blkno = bn; while (n-- > 0) *ptr++ = cpu_to_be64(bn++); - if (zero_new) { - ret = sb_issue_zeroout(sb, *dblock, *dblks, - GFP_NOFS); + if (flags & IOMAP_ZERO) { + ret = sb_issue_zeroout(sb, iomap->blkno, + dblks, GFP_NOFS); if (ret) { fs_err(sdp, "Failed to zero data buffers\n"); + flags &= ~IOMAP_ZERO; } } break; } - } while ((state != ALLOC_DATA) || !(*dblock)); + } while (iomap->blkno == IOMAP_NULL_BLOCK); + 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); @@ -644,47 +645,101 @@ static int gfs2_bmap_alloc(struct inode *inode, const sector_t lblock, } /** - * 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 + * hole_size - figure out the size of a hole + * @ip: The inode + * @lblock: The logical starting block number + * @mp: The metapath * - * 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: The hole size in bytes * - * Returns: errno */ +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; -int gfs2_block_map(struct inode *inode, sector_t lblock, - struct buffer_head *bh_map, int create) + 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; +} + +/** + * gfs2_get_iomap - 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_get_iomap(struct inode *inode, loff_t pos, ssize_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 bsize = sdp->sd_sb.sb_bsize; - const size_t maxlen = bh_map->b_size >> inode->i_blkbits; const u64 *arr = sdp->sd_heightsize; __be64 *ptr; - u64 size; - struct metapath mp; + sector_t lblock = pos >> inode->i_blkbits; + sector_t lend = (pos + length + sdp->sd_sb.sb_bsize - 1) >> inode->i_blkbits; int ret; - int eob; + int eob = 0; unsigned int len; struct buffer_head *bh; u8 height; - bool zero_new = false; - sector_t dblock = 0; - unsigned dblks; - BUG_ON(maxlen == 0); + trace_gfs2_iomap_start(ip, pos, length, flags); + if (!length) { + ret = -EINVAL; + goto out; + } + + iomap->offset = lblock << inode->i_blkbits; + iomap->blkno = IOMAP_NULL_BLOCK; + iomap->type = IOMAP_HOLE; + iomap->length = (u64)(lend - lblock) << inode->i_blkbits; + iomap->flags = 0; + bmap_lock(ip, 0); - memset(&mp, 0, sizeof(mp)); - bmap_lock(ip, create); - 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 (gfs2_is_dir(ip)) { bsize = sdp->sd_jbsize; arr = sdp->sd_jheightsize; @@ -692,56 +747,110 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, ret = gfs2_meta_inode_buffer(ip, &mp.mp_bh[0]); if (ret) - goto out; + goto out_release; height = ip->i_height; - size = (lblock + 1) * bsize; - while (size > arr[height]) + while ((lblock + 1) * bsize > arr[height]) height++; find_metapath(sdp, lblock, &mp, height); - mp.mp_aheight = 1; if (height > ip->i_height || gfs2_is_stuffed(ip)) goto do_alloc; + ret = lookup_metapath(ip, &mp); if (ret < 0) - goto out; + 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; - map_bh(bh_map, inode->i_sb, be64_to_cpu(*ptr)); + + iomap->type = IOMAP_MAPPED; + iomap->blkno = be64_to_cpu(*ptr); + bh = mp.mp_bh[ip->i_height - 1]; - len = gfs2_extent_length(bh->b_data, bh->b_size, ptr, maxlen, &eob); - bh_map->b_size = (len << inode->i_blkbits); + len = gfs2_extent_length(bh->b_data, bh->b_size, ptr, lend - lblock, &eob); if (eob) - set_buffer_boundary(bh_map); + iomap->flags |= IOMAP_F_BOUNDARY; + iomap->length = (u64)len << inode->i_blkbits; + ret = 0; -out: + +out_release: release_metapath(&mp); - trace_gfs2_bmap(ip, bh_map, lblock, create, ret); - bmap_unlock(ip, create); + bmap_unlock(ip, 0); +out: + trace_gfs2_iomap_end(ip, iomap, ret); return ret; do_alloc: - /* All allocations are done here, firstly check create flag */ - if (!create) { + if (!(flags & IOMAP_WRITE)) { + if (pos >= i_size_read(inode)) { + ret = -ENOENT; + goto out_release; + } BUG_ON(gfs2_is_stuffed(ip)); ret = 0; - goto out; + iomap->length = hole_size(inode, lblock, &mp); + goto out_release; } - /* At this point ret is the tree depth of already allocated blocks */ + 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 gfs2_sbd *sdp = GFS2_SB(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)) - zero_new = true; - ret = gfs2_bmap_alloc(inode, lblock, zero_new, &mp, maxlen, &dblock, - &dblks); - if (ret == 0) { - map_bh(bh_map, inode->i_sb, dblock); - bh_map->b_size = dblks << inode->i_blkbits; + flags |= IOMAP_ZERO; + ret = gfs2_get_iomap(inode, lblock << sdp->sd_sb.sb_bsize_shift, + bh_map->b_size, flags, &iomap); + if (ret) + goto out; + + iomap.length = round_up(iomap.length, sdp->sd_sb.sb_bsize); + bh_map->b_size = iomap.length; + if (iomap.flags & IOMAP_F_BOUNDARY) + set_buffer_boundary(bh_map); + if (iomap.blkno != IOMAP_NULL_BLOCK) + map_bh(bh_map, inode->i_sb, iomap.blkno); + bh_map->b_size = iomap.length; + clear_buffer_zeronew(bh_map); + if (iomap.flags & IOMAP_F_NEW) set_buffer_new(bh_map); - } - goto out; + +out: + trace_gfs2_bmap(ip, bh_map, lblock, create, ret); + return ret; } /* diff --git a/fs/gfs2/bmap.h b/fs/gfs2/bmap.h index 81ded5e..e904aed 100644 --- a/fs/gfs2/bmap.h +++ b/fs/gfs2/bmap.h @@ -10,6 +10,8 @@ #ifndef __BMAP_DOT_H__ #define __BMAP_DOT_H__ +#include <linux/iomap.h> + #include "inode.h" struct inode; @@ -47,6 +49,8 @@ static inline void gfs2_write_calc_reserv(const struct gfs2_inode *ip, extern int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page); extern int gfs2_block_map(struct inode *inode, sector_t lblock, struct buffer_head *bh, int create); +extern int gfs2_get_iomap(struct inode *inode, loff_t pos, ssize_t length, + unsigned flags, struct iomap *iomap); extern int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen); extern int gfs2_setattr_size(struct inode *inode, u64 size); diff --git a/fs/gfs2/trace_gfs2.h b/fs/gfs2/trace_gfs2.h index 49ac55d..3c91ae3 100644 --- a/fs/gfs2/trace_gfs2.h +++ b/fs/gfs2/trace_gfs2.h @@ -12,6 +12,7 @@ #include <linux/gfs2_ondisk.h> #include <linux/writeback.h> #include <linux/ktime.h> +#include <linux/iomap.h> #include "incore.h" #include "glock.h" #include "rgrp.h" @@ -469,6 +470,70 @@ TRACE_EVENT(gfs2_bmap, __entry->errno) ); +TRACE_EVENT(gfs2_iomap_start, + + TP_PROTO(const struct gfs2_inode *ip, loff_t pos, ssize_t length, + u16 flags), + + TP_ARGS(ip, pos, length, flags), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field( u64, inum ) + __field( loff_t, pos ) + __field( ssize_t, length ) + __field( u16, flags ) + ), + + TP_fast_assign( + __entry->dev = ip->i_gl->gl_name.ln_sbd->sd_vfs->s_dev; + __entry->inum = ip->i_no_addr; + __entry->pos = pos; + __entry->length = length; + __entry->flags = flags; + ), + + TP_printk("%u,%u bmap %llu iomap start %llu/%lu flags:%08x", + MAJOR(__entry->dev), MINOR(__entry->dev), + (unsigned long long)__entry->inum, + (unsigned long long)__entry->pos, + (unsigned long)__entry->length, (u16)__entry->flags) +); + +TRACE_EVENT(gfs2_iomap_end, + + TP_PROTO(const struct gfs2_inode *ip, struct iomap *iomap, int ret), + + TP_ARGS(ip, iomap, ret), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field( u64, inum ) + __field( loff_t, offset ) + __field( ssize_t, length ) + __field( u16, flags ) + __field( u16, type ) + __field( int, ret ) + ), + + TP_fast_assign( + __entry->dev = ip->i_gl->gl_name.ln_sbd->sd_vfs->s_dev; + __entry->inum = ip->i_no_addr; + __entry->offset = iomap->offset; + __entry->length = iomap->length; + __entry->flags = iomap->flags; + __entry->type = iomap->type; + __entry->ret = ret; + ), + + TP_printk("%u,%u bmap %llu iomap end %llu/%lu ty:%d flags:%08x rc:%d", + MAJOR(__entry->dev), MINOR(__entry->dev), + (unsigned long long)__entry->inum, + (unsigned long long)__entry->offset, + (unsigned long)__entry->length, (u16)__entry->type, + (u16)__entry->flags, __entry->ret) +); + /* Keep track of blocks as they are allocated/freed */ TRACE_EVENT(gfs2_block_alloc, diff --git a/include/linux/iomap.h b/include/linux/iomap.h index ff89026..4dfdb22 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -21,7 +21,8 @@ struct vm_fault; /* * Flags for all iomap mappings: */ -#define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */ +#define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */ +#define IOMAP_F_BOUNDARY 0x02 /* mapping ends at metadata boundary */ /* * Flags that only need to be reported for IOMAP_REPORT requests: -- 2.7.5
