diff options
Diffstat (limited to 'fs/jbd2/journal.c')
-rw-r--r-- | fs/jbd2/journal.c | 91 |
1 files changed, 29 insertions, 62 deletions
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 9a7826990304..0dfa5b598e68 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c | |||
@@ -2078,10 +2078,9 @@ static void journal_free_journal_head(struct journal_head *jh) | |||
2078 | * When a buffer has its BH_JBD bit set it is immune from being released by | 2078 | * When a buffer has its BH_JBD bit set it is immune from being released by |
2079 | * core kernel code, mainly via ->b_count. | 2079 | * core kernel code, mainly via ->b_count. |
2080 | * | 2080 | * |
2081 | * A journal_head may be detached from its buffer_head when the journal_head's | 2081 | * A journal_head is detached from its buffer_head when the journal_head's |
2082 | * b_transaction, b_cp_transaction and b_next_transaction pointers are NULL. | 2082 | * b_jcount reaches zero. Running transaction (b_transaction) and checkpoint |
2083 | * Various places in JBD call jbd2_journal_remove_journal_head() to indicate that the | 2083 | * transaction (b_cp_transaction) hold their references to b_jcount. |
2084 | * journal_head can be dropped if needed. | ||
2085 | * | 2084 | * |
2086 | * Various places in the kernel want to attach a journal_head to a buffer_head | 2085 | * Various places in the kernel want to attach a journal_head to a buffer_head |
2087 | * _before_ attaching the journal_head to a transaction. To protect the | 2086 | * _before_ attaching the journal_head to a transaction. To protect the |
@@ -2094,17 +2093,16 @@ static void journal_free_journal_head(struct journal_head *jh) | |||
2094 | * (Attach a journal_head if needed. Increments b_jcount) | 2093 | * (Attach a journal_head if needed. Increments b_jcount) |
2095 | * struct journal_head *jh = jbd2_journal_add_journal_head(bh); | 2094 | * struct journal_head *jh = jbd2_journal_add_journal_head(bh); |
2096 | * ... | 2095 | * ... |
2096 | * (Get another reference for transaction) | ||
2097 | * jbd2_journal_grab_journal_head(bh); | ||
2097 | * jh->b_transaction = xxx; | 2098 | * jh->b_transaction = xxx; |
2099 | * (Put original reference) | ||
2098 | * jbd2_journal_put_journal_head(jh); | 2100 | * jbd2_journal_put_journal_head(jh); |
2099 | * | ||
2100 | * Now, the journal_head's b_jcount is zero, but it is safe from being released | ||
2101 | * because it has a non-zero b_transaction. | ||
2102 | */ | 2101 | */ |
2103 | 2102 | ||
2104 | /* | 2103 | /* |
2105 | * Give a buffer_head a journal_head. | 2104 | * Give a buffer_head a journal_head. |
2106 | * | 2105 | * |
2107 | * Doesn't need the journal lock. | ||
2108 | * May sleep. | 2106 | * May sleep. |
2109 | */ | 2107 | */ |
2110 | struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh) | 2108 | struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh) |
@@ -2168,61 +2166,29 @@ static void __journal_remove_journal_head(struct buffer_head *bh) | |||
2168 | struct journal_head *jh = bh2jh(bh); | 2166 | struct journal_head *jh = bh2jh(bh); |
2169 | 2167 | ||
2170 | J_ASSERT_JH(jh, jh->b_jcount >= 0); | 2168 | J_ASSERT_JH(jh, jh->b_jcount >= 0); |
2171 | 2169 | J_ASSERT_JH(jh, jh->b_transaction == NULL); | |
2172 | get_bh(bh); | 2170 | J_ASSERT_JH(jh, jh->b_next_transaction == NULL); |
2173 | if (jh->b_jcount == 0) { | 2171 | J_ASSERT_JH(jh, jh->b_cp_transaction == NULL); |
2174 | if (jh->b_transaction == NULL && | 2172 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); |
2175 | jh->b_next_transaction == NULL && | 2173 | J_ASSERT_BH(bh, buffer_jbd(bh)); |
2176 | jh->b_cp_transaction == NULL) { | 2174 | J_ASSERT_BH(bh, jh2bh(jh) == bh); |
2177 | J_ASSERT_JH(jh, jh->b_jlist == BJ_None); | 2175 | BUFFER_TRACE(bh, "remove journal_head"); |
2178 | J_ASSERT_BH(bh, buffer_jbd(bh)); | 2176 | if (jh->b_frozen_data) { |
2179 | J_ASSERT_BH(bh, jh2bh(jh) == bh); | 2177 | printk(KERN_WARNING "%s: freeing b_frozen_data\n", __func__); |
2180 | BUFFER_TRACE(bh, "remove journal_head"); | 2178 | jbd2_free(jh->b_frozen_data, bh->b_size); |
2181 | if (jh->b_frozen_data) { | ||
2182 | printk(KERN_WARNING "%s: freeing " | ||
2183 | "b_frozen_data\n", | ||
2184 | __func__); | ||
2185 | jbd2_free(jh->b_frozen_data, bh->b_size); | ||
2186 | } | ||
2187 | if (jh->b_committed_data) { | ||
2188 | printk(KERN_WARNING "%s: freeing " | ||
2189 | "b_committed_data\n", | ||
2190 | __func__); | ||
2191 | jbd2_free(jh->b_committed_data, bh->b_size); | ||
2192 | } | ||
2193 | bh->b_private = NULL; | ||
2194 | jh->b_bh = NULL; /* debug, really */ | ||
2195 | clear_buffer_jbd(bh); | ||
2196 | __brelse(bh); | ||
2197 | journal_free_journal_head(jh); | ||
2198 | } else { | ||
2199 | BUFFER_TRACE(bh, "journal_head was locked"); | ||
2200 | } | ||
2201 | } | 2179 | } |
2180 | if (jh->b_committed_data) { | ||
2181 | printk(KERN_WARNING "%s: freeing b_committed_data\n", __func__); | ||
2182 | jbd2_free(jh->b_committed_data, bh->b_size); | ||
2183 | } | ||
2184 | bh->b_private = NULL; | ||
2185 | jh->b_bh = NULL; /* debug, really */ | ||
2186 | clear_buffer_jbd(bh); | ||
2187 | journal_free_journal_head(jh); | ||
2202 | } | 2188 | } |
2203 | 2189 | ||
2204 | /* | 2190 | /* |
2205 | * jbd2_journal_remove_journal_head(): if the buffer isn't attached to a transaction | 2191 | * Drop a reference on the passed journal_head. If it fell to zero then |
2206 | * and has a zero b_jcount then remove and release its journal_head. If we did | ||
2207 | * see that the buffer is not used by any transaction we also "logically" | ||
2208 | * decrement ->b_count. | ||
2209 | * | ||
2210 | * We in fact take an additional increment on ->b_count as a convenience, | ||
2211 | * because the caller usually wants to do additional things with the bh | ||
2212 | * after calling here. | ||
2213 | * The caller of jbd2_journal_remove_journal_head() *must* run __brelse(bh) at some | ||
2214 | * time. Once the caller has run __brelse(), the buffer is eligible for | ||
2215 | * reaping by try_to_free_buffers(). | ||
2216 | */ | ||
2217 | void jbd2_journal_remove_journal_head(struct buffer_head *bh) | ||
2218 | { | ||
2219 | jbd_lock_bh_journal_head(bh); | ||
2220 | __journal_remove_journal_head(bh); | ||
2221 | jbd_unlock_bh_journal_head(bh); | ||
2222 | } | ||
2223 | |||
2224 | /* | ||
2225 | * Drop a reference on the passed journal_head. If it fell to zero then try to | ||
2226 | * release the journal_head from the buffer_head. | 2192 | * release the journal_head from the buffer_head. |
2227 | */ | 2193 | */ |
2228 | void jbd2_journal_put_journal_head(struct journal_head *jh) | 2194 | void jbd2_journal_put_journal_head(struct journal_head *jh) |
@@ -2232,11 +2198,12 @@ void jbd2_journal_put_journal_head(struct journal_head *jh) | |||
2232 | jbd_lock_bh_journal_head(bh); | 2198 | jbd_lock_bh_journal_head(bh); |
2233 | J_ASSERT_JH(jh, jh->b_jcount > 0); | 2199 | J_ASSERT_JH(jh, jh->b_jcount > 0); |
2234 | --jh->b_jcount; | 2200 | --jh->b_jcount; |
2235 | if (!jh->b_jcount && !jh->b_transaction) { | 2201 | if (!jh->b_jcount) { |
2236 | __journal_remove_journal_head(bh); | 2202 | __journal_remove_journal_head(bh); |
2203 | jbd_unlock_bh_journal_head(bh); | ||
2237 | __brelse(bh); | 2204 | __brelse(bh); |
2238 | } | 2205 | } else |
2239 | jbd_unlock_bh_journal_head(bh); | 2206 | jbd_unlock_bh_journal_head(bh); |
2240 | } | 2207 | } |
2241 | 2208 | ||
2242 | /* | 2209 | /* |