[Verse 1] Deep beneath the filesystem's facade Character streams await your call Byte by byte they whisper secrets Through the kernel's protocol No buffering masks their essence Raw data flows like liquid gold While block devices guard their sectors In chunks four-K stories told [Chorus] Char reads one, block reads many File ops bridge the gap between Read write open close and seeking Through the driver's pristine sheen Character flows, block device knows How to cache and optimize Memory maps and buffer heads Make the storage synchronize [Verse 2] Registration calls the kernel "Here's my major number, sir" Character device nodes waiting In dev directory's chamber Block devices need more structure Request queues and bio chains Elevator algorithms dancing Through the I/O domain's reins [Chorus] Char reads one, block reads many File ops bridge the gap between Read write open close and seeking Through the driver's pristine sheen Character flows, block device knows How to cache and optimize Memory maps and buffer heads Make the storage synchronize [Bridge] Copy to user, copy from user Kernel space protects the realm Spinlocks guard the critical sections While interrupts overwhelm Block layer abstracts the hardware Scatter-gather lists align Page cache holds the precious data Till the writeback stars align [Verse 3] Poll and select wake sleeping processes When the device has tales to tell Character drivers stay connected To their hardware's magic spell While block devices batch requests Merging seeks for throughput gains Every sector tells a story Through the storage system's veins [Chorus] Char reads one, block reads many File ops bridge the gap between Read write open close and seeking Through the driver's pristine sheen Character flows, block device knows How to cache and optimize Memory maps and buffer heads Make the storage synchronize [Outro] From terminal's gentle keystrokes To the disk's persistent might Character and block devices Bridge the gap from dark to light
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