diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-21 12:32:08 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-21 12:32:08 -0800 |
commit | eae21770b4fed5597623aad0d618190fa60426ff (patch) | |
tree | 23c59fb7a33e93a79525e2b10d56df54d40049d1 /fs/fat/cache.c | |
parent | e9f57ebcba563e0cd532926cab83c92bb4d79360 (diff) | |
parent | 9f273c24ec5f4a6f785bb83e931b3808a07b459e (diff) |
Merge branch 'akpm' (patches from Andrew)
Merge third patch-bomb from Andrew Morton:
"I'm pretty much done for -rc1 now:
- the rest of MM, basically
- lib/ updates
- checkpatch, epoll, hfs, fatfs, ptrace, coredump, exit
- cpu_mask simplifications
- kexec, rapidio, MAINTAINERS etc, etc.
- more dma-mapping cleanups/simplifications from hch"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (109 commits)
MAINTAINERS: add/fix git URLs for various subsystems
mm: memcontrol: add "sock" to cgroup2 memory.stat
mm: memcontrol: basic memory statistics in cgroup2 memory controller
mm: memcontrol: do not uncharge old page in page cache replacement
Documentation: cgroup: add memory.swap.{current,max} description
mm: free swap cache aggressively if memcg swap is full
mm: vmscan: do not scan anon pages if memcg swap limit is hit
swap.h: move memcg related stuff to the end of the file
mm: memcontrol: replace mem_cgroup_lruvec_online with mem_cgroup_online
mm: vmscan: pass memcg to get_scan_count()
mm: memcontrol: charge swap to cgroup2
mm: memcontrol: clean up alloc, online, offline, free functions
mm: memcontrol: flatten struct cg_proto
mm: memcontrol: rein in the CONFIG space madness
net: drop tcp_memcontrol.c
mm: memcontrol: introduce CONFIG_MEMCG_LEGACY_KMEM
mm: memcontrol: allow to disable kmem accounting for cgroup2
mm: memcontrol: account "kmem" consumers in cgroup2 memory controller
mm: memcontrol: move kmem accounting code to CONFIG_MEMCG
mm: memcontrol: separate kmem code from legacy tcp accounting code
...
Diffstat (limited to 'fs/fat/cache.c')
-rw-r--r-- | fs/fat/cache.c | 79 |
1 files changed, 54 insertions, 25 deletions
diff --git a/fs/fat/cache.c b/fs/fat/cache.c index 93fc62232ec2..5d384921524d 100644 --- a/fs/fat/cache.c +++ b/fs/fat/cache.c @@ -301,15 +301,59 @@ static int fat_bmap_cluster(struct inode *inode, int cluster) return dclus; } -int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, - unsigned long *mapped_blocks, int create) +int fat_get_mapped_cluster(struct inode *inode, sector_t sector, + sector_t last_block, + unsigned long *mapped_blocks, sector_t *bmap) { struct super_block *sb = inode->i_sb; struct msdos_sb_info *sbi = MSDOS_SB(sb); + int cluster, offset; + + cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits); + offset = sector & (sbi->sec_per_clus - 1); + cluster = fat_bmap_cluster(inode, cluster); + if (cluster < 0) + return cluster; + else if (cluster) { + *bmap = fat_clus_to_blknr(sbi, cluster) + offset; + *mapped_blocks = sbi->sec_per_clus - offset; + if (*mapped_blocks > last_block - sector) + *mapped_blocks = last_block - sector; + } + + return 0; +} + +static int is_exceed_eof(struct inode *inode, sector_t sector, + sector_t *last_block, int create) +{ + struct super_block *sb = inode->i_sb; const unsigned long blocksize = sb->s_blocksize; const unsigned char blocksize_bits = sb->s_blocksize_bits; + + *last_block = (i_size_read(inode) + (blocksize - 1)) >> blocksize_bits; + if (sector >= *last_block) { + if (!create) + return 1; + + /* + * ->mmu_private can access on only allocation path. + * (caller must hold ->i_mutex) + */ + *last_block = (MSDOS_I(inode)->mmu_private + (blocksize - 1)) + >> blocksize_bits; + if (sector >= *last_block) + return 1; + } + + return 0; +} + +int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, + unsigned long *mapped_blocks, int create, bool from_bmap) +{ + struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); sector_t last_block; - int cluster, offset; *phys = 0; *mapped_blocks = 0; @@ -321,31 +365,16 @@ int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, return 0; } - last_block = (i_size_read(inode) + (blocksize - 1)) >> blocksize_bits; - if (sector >= last_block) { - if (!create) + if (!from_bmap) { + if (is_exceed_eof(inode, sector, &last_block, create)) return 0; - - /* - * ->mmu_private can access on only allocation path. - * (caller must hold ->i_mutex) - */ - last_block = (MSDOS_I(inode)->mmu_private + (blocksize - 1)) - >> blocksize_bits; + } else { + last_block = inode->i_blocks >> + (inode->i_sb->s_blocksize_bits - 9); if (sector >= last_block) return 0; } - cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits); - offset = sector & (sbi->sec_per_clus - 1); - cluster = fat_bmap_cluster(inode, cluster); - if (cluster < 0) - return cluster; - else if (cluster) { - *phys = fat_clus_to_blknr(sbi, cluster) + offset; - *mapped_blocks = sbi->sec_per_clus - offset; - if (*mapped_blocks > last_block - sector) - *mapped_blocks = last_block - sector; - } - return 0; + return fat_get_mapped_cluster(inode, sector, last_block, mapped_blocks, + phys); } |