From 511bea5ea2b2b330e67c9e58ffb5027caebf9052 Mon Sep 17 00:00:00 2001 From: Anton Altaparmakov Date: Tue, 4 Oct 2005 14:24:21 +0100 Subject: NTFS: - Change {__,}ntfs_cluster_free() to also take an optional attribute search context as argument. This allows calling it with the mft record mapped. Update all callers. - Fix potential deadlock in ntfs_mft_data_extend_allocation_nolock() error handling by passing in the active search context when calling ntfs_cluster_free(). Signed-off-by: Anton Altaparmakov --- fs/ntfs/ChangeLog | 11 +++++++---- fs/ntfs/lcnalloc.c | 41 +++++++++++++++++++++++++++++++++++------ fs/ntfs/lcnalloc.h | 40 +++++++++++++++++++++++++++++++++++----- fs/ntfs/mft.c | 13 +++++++++---- 4 files changed, 86 insertions(+), 19 deletions(-) (limited to 'fs/ntfs') diff --git a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog index 0a361ddb3b4..6e4f44eed6f 100644 --- a/fs/ntfs/ChangeLog +++ b/fs/ntfs/ChangeLog @@ -24,10 +24,13 @@ ToDo/Notes: 2.1.25-WIP - - Change ntfs_map_runlist_nolock() and ntfs_attr_find_vcn_nolock() to - also take an optional attribute search context as argument. This - allows calling these functions with the mft record mapped. Update - all callers. + - Change ntfs_map_runlist_nolock(), ntfs_attr_find_vcn_nolock() and + {__,}ntfs_cluster_free() to also take an optional attribute search + context as argument. This allows calling these functions with the + mft record mapped. Update all callers. + - Fix potential deadlock in ntfs_mft_data_extend_allocation_nolock() + error handling by passing in the active search context when calling + ntfs_cluster_free(). 2.1.24 - Lots of bug fixes and support more clean journal states. diff --git a/fs/ntfs/lcnalloc.c b/fs/ntfs/lcnalloc.c index 8e60c47fafa..75313f4307e 100644 --- a/fs/ntfs/lcnalloc.c +++ b/fs/ntfs/lcnalloc.c @@ -782,6 +782,7 @@ out: * @ni: ntfs inode whose runlist describes the clusters to free * @start_vcn: vcn in the runlist of @ni at which to start freeing clusters * @count: number of clusters to free or -1 for all clusters + * @ctx: active attribute search context if present or NULL if not * @is_rollback: true if this is a rollback operation * * Free @count clusters starting at the cluster @start_vcn in the runlist @@ -791,15 +792,39 @@ out: * deallocated. Thus, to completely free all clusters in a runlist, use * @start_vcn = 0 and @count = -1. * + * If @ctx is specified, it is an active search context of @ni and its base mft + * record. This is needed when __ntfs_cluster_free() encounters unmapped + * runlist fragments and allows their mapping. If you do not have the mft + * record mapped, you can specify @ctx as NULL and __ntfs_cluster_free() will + * perform the necessary mapping and unmapping. + * + * Note, __ntfs_cluster_free() saves the state of @ctx on entry and restores it + * before returning. Thus, @ctx will be left pointing to the same attribute on + * return as on entry. However, the actual pointers in @ctx may point to + * different memory locations on return, so you must remember to reset any + * cached pointers from the @ctx, i.e. after the call to __ntfs_cluster_free(), + * you will probably want to do: + * m = ctx->mrec; + * a = ctx->attr; + * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that + * you cache ctx->mrec in a variable @m of type MFT_RECORD *. + * * @is_rollback should always be FALSE, it is for internal use to rollback * errors. You probably want to use ntfs_cluster_free() instead. * - * Note, ntfs_cluster_free() does not modify the runlist at all, so the caller - * has to deal with it later. + * Note, __ntfs_cluster_free() does not modify the runlist, so you have to + * remove from the runlist or mark sparse the freed runs later. * * Return the number of deallocated clusters (not counting sparse ones) on * success and -errno on error. * + * WARNING: If @ctx is supplied, regardless of whether success or failure is + * returned, you need to check IS_ERR(@ctx->mrec) and if TRUE the @ctx + * is no longer valid, i.e. you need to either call + * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it. + * In that case PTR_ERR(@ctx->mrec) will give you the error code for + * why the mapping of the old inode failed. + * * Locking: - The runlist described by @ni must be locked for writing on entry * and is locked on return. Note the runlist may be modified when * needed runlist fragments need to be mapped. @@ -807,9 +832,13 @@ out: * on return. * - This function takes the volume lcn bitmap lock for writing and * modifies the bitmap contents. + * - If @ctx is NULL, the base mft record of @ni must not be mapped on + * entry and it will be left unmapped on return. + * - If @ctx is not NULL, the base mft record must be mapped on entry + * and it will be left mapped on return. */ s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count, - const BOOL is_rollback) + ntfs_attr_search_ctx *ctx, const BOOL is_rollback) { s64 delta, to_free, total_freed, real_freed; ntfs_volume *vol; @@ -839,7 +868,7 @@ s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count, total_freed = real_freed = 0; - rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, NULL); + rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, ctx); if (IS_ERR(rl)) { if (!is_rollback) ntfs_error(vol->sb, "Failed to find first runlist " @@ -893,7 +922,7 @@ s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count, /* Attempt to map runlist. */ vcn = rl->vcn; - rl = ntfs_attr_find_vcn_nolock(ni, vcn, NULL); + rl = ntfs_attr_find_vcn_nolock(ni, vcn, ctx); if (IS_ERR(rl)) { err = PTR_ERR(rl); if (!is_rollback) @@ -961,7 +990,7 @@ err_out: * If rollback fails, set the volume errors flag, emit an error * message, and return the error code. */ - delta = __ntfs_cluster_free(ni, start_vcn, total_freed, TRUE); + delta = __ntfs_cluster_free(ni, start_vcn, total_freed, ctx, TRUE); if (delta < 0) { ntfs_error(vol->sb, "Failed to rollback (error %i). Leaving " "inconsistent metadata! Unmount and run " diff --git a/fs/ntfs/lcnalloc.h b/fs/ntfs/lcnalloc.h index a6a8827882e..aa0518509cd 100644 --- a/fs/ntfs/lcnalloc.h +++ b/fs/ntfs/lcnalloc.h @@ -27,6 +27,7 @@ #include +#include "attrib.h" #include "types.h" #include "inode.h" #include "runlist.h" @@ -44,13 +45,14 @@ extern runlist_element *ntfs_cluster_alloc(ntfs_volume *vol, const NTFS_CLUSTER_ALLOCATION_ZONES zone); extern s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, - s64 count, const BOOL is_rollback); + s64 count, ntfs_attr_search_ctx *ctx, const BOOL is_rollback); /** * ntfs_cluster_free - free clusters on an ntfs volume * @ni: ntfs inode whose runlist describes the clusters to free * @start_vcn: vcn in the runlist of @ni at which to start freeing clusters * @count: number of clusters to free or -1 for all clusters + * @ctx: active attribute search context if present or NULL if not * * Free @count clusters starting at the cluster @start_vcn in the runlist * described by the ntfs inode @ni. @@ -59,12 +61,36 @@ extern s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, * deallocated. Thus, to completely free all clusters in a runlist, use * @start_vcn = 0 and @count = -1. * - * Note, ntfs_cluster_free() does not modify the runlist at all, so the caller - * has to deal with it later. + * If @ctx is specified, it is an active search context of @ni and its base mft + * record. This is needed when ntfs_cluster_free() encounters unmapped runlist + * fragments and allows their mapping. If you do not have the mft record + * mapped, you can specify @ctx as NULL and ntfs_cluster_free() will perform + * the necessary mapping and unmapping. + * + * Note, ntfs_cluster_free() saves the state of @ctx on entry and restores it + * before returning. Thus, @ctx will be left pointing to the same attribute on + * return as on entry. However, the actual pointers in @ctx may point to + * different memory locations on return, so you must remember to reset any + * cached pointers from the @ctx, i.e. after the call to ntfs_cluster_free(), + * you will probably want to do: + * m = ctx->mrec; + * a = ctx->attr; + * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that + * you cache ctx->mrec in a variable @m of type MFT_RECORD *. + * + * Note, ntfs_cluster_free() does not modify the runlist, so you have to remove + * from the runlist or mark sparse the freed runs later. * * Return the number of deallocated clusters (not counting sparse ones) on * success and -errno on error. * + * WARNING: If @ctx is supplied, regardless of whether success or failure is + * returned, you need to check IS_ERR(@ctx->mrec) and if TRUE the @ctx + * is no longer valid, i.e. you need to either call + * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it. + * In that case PTR_ERR(@ctx->mrec) will give you the error code for + * why the mapping of the old inode failed. + * * Locking: - The runlist described by @ni must be locked for writing on entry * and is locked on return. Note the runlist may be modified when * needed runlist fragments need to be mapped. @@ -72,11 +98,15 @@ extern s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, * on return. * - This function takes the volume lcn bitmap lock for writing and * modifies the bitmap contents. + * - If @ctx is NULL, the base mft record of @ni must not be mapped on + * entry and it will be left unmapped on return. + * - If @ctx is not NULL, the base mft record must be mapped on entry + * and it will be left mapped on return. */ static inline s64 ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, - s64 count) + s64 count, ntfs_attr_search_ctx *ctx) { - return __ntfs_cluster_free(ni, start_vcn, count, FALSE); + return __ntfs_cluster_free(ni, start_vcn, count, ctx, FALSE); } extern int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol, diff --git a/fs/ntfs/mft.c b/fs/ntfs/mft.c index 15df34f6203..5577fc6e190 100644 --- a/fs/ntfs/mft.c +++ b/fs/ntfs/mft.c @@ -1952,20 +1952,21 @@ restore_undo_alloc: NVolSetErrors(vol); return ret; } - a = ctx->attr; - a->data.non_resident.highest_vcn = cpu_to_sle64(old_last_vcn - 1); + ctx->attr->data.non_resident.highest_vcn = + cpu_to_sle64(old_last_vcn - 1); undo_alloc: - if (ntfs_cluster_free(mft_ni, old_last_vcn, -1) < 0) { + if (ntfs_cluster_free(mft_ni, old_last_vcn, -1, ctx) < 0) { ntfs_error(vol->sb, "Failed to free clusters from mft data " "attribute.%s", es); NVolSetErrors(vol); } + a = ctx->attr; if (ntfs_rl_truncate_nolock(vol, &mft_ni->runlist, old_last_vcn)) { ntfs_error(vol->sb, "Failed to truncate mft data attribute " "runlist.%s", es); NVolSetErrors(vol); } - if (mp_rebuilt) { + if (mp_rebuilt && !IS_ERR(ctx->mrec)) { if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu( a->data.non_resident.mapping_pairs_offset), old_alen - le16_to_cpu( @@ -1982,6 +1983,10 @@ undo_alloc: } flush_dcache_mft_record_page(ctx->ntfs_ino); mark_mft_record_dirty(ctx->ntfs_ino); + } else if (IS_ERR(ctx->mrec)) { + ntfs_error(vol->sb, "Failed to restore attribute search " + "context.%s", es); + NVolSetErrors(vol); } if (ctx) ntfs_attr_put_search_ctx(ctx); -- cgit v1.2.3